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Both energy and heat can be expressed in units of what? | ohms | amperes | velocities | joules | Energy and heat are expressed in units of joules. |
In fact, when sitting in the sun, many ectothermic lizards have higher body temperatures than what? | primates | carnivores | insects | mammals | |
In binary fission how many times does a cell split? | six | four | one | two | In binary fission, a cell splits in two. First, the large circular chromosome is copied. Then the cell divides to form two new daughter cells. Each has a copy of the parent cell's chromosome. |
What do nonvascular plants reproduce with? | vascular plants | photosynthesis | toxins | spores | Nonvascular plants are low-growing, reproduce with spores, and need a moist habitat. |
The most powerful or influential individual in a group is sometimes called what? | beta | superior | gamma | dominant | The most powerful or influential individual in a group is sometimes called dominant. In genetics, a dominant trait means nearly the same thing. A dominant trait is the most influential trait and masks the other trait. |
What is the first stage of cellular respiration? | hydrolysis | photosynthesis | amniocentesis | glycolysis | |
In which direction does heat always flow through objects? | from left to right | from low to high | from cooler to hotter | from hotter to cooler | The objects are at different temperatures, and heat flows from the hotter to the cooler object. This is always. |
Like sharks, nearly the entire human skeleton during a specific pre-birth developmental stage is made of what connective tissue? | collagen | chloroplasm | phloem | cartilage | Cartilage Cartilage is a connective tissue with a large amount of the matrix and variable amounts of fibers. The cells, called chondrocytes, make the matrix and fibers of the tissue. Chondrocytes are found in spaces within the tissue called lacunae. A cartilage with few collagen and elastic fibers is hyaline cartilage, illustrated in Figure 33.14. The lacunae are randomly scattered throughout the tissue and the matrix takes on a milky or scrubbed appearance with routine histological stains. Sharks have cartilaginous skeletons, as does nearly the entire human skeleton during a specific pre-birth developmental stage. A remnant of this cartilage persists in the outer portion of the human nose. Hyaline cartilage is also found at the ends of long bones, reducing friction and cushioning the articulations of these bones. |
When this forms underground, volcanoes rise? | CO2 | pumice | soil | magma | Volcanoes rise where magma forms underground. Volcanoes are found at convergent plate boundaries and at hotspots. Volcanic activity is found at divergent plate boundaries. The map in Figure below shows where volcanoes are located. |
Hormones produced by what gland in the neck increase the rate of metabolism in cells throughout the body? | thymus | pituitary | kidney | thyroid | The thyroid gland is a large gland in the neck. Thyroid hormones increase the rate of metabolism in cells throughout the body. They control how quickly cells use energy and make proteins. |
When the ventricles begin to contract, pressure within the ventricles rises and blood flows toward the area of lowest pressure, which is initially in the atria. this backflow causes the cusps of the tricuspid and mitral (bicuspid) valves to close. these valves are tied down to the papillary muscles by these? | photoreactive tendineae | chollphyide tendineae | choanocyte tendineae | chordae tendineae | When the ventricles begin to contract, pressure within the ventricles rises and blood flows toward the area of lowest pressure, which is initially in the atria. This backflow causes the cusps of the tricuspid and mitral (bicuspid) valves to close. These valves are tied down to the papillary muscles by chordae tendineae. During the relaxation phase of the cardiac cycle, the papillary muscles are also relaxed and the tension on the chordae tendineae is slight (see Figure 19.13b). However, as the myocardium of the ventricle contracts, so do the papillary muscles. This creates tension on the chordae tendineae (see Figure 19.14b), helping to hold the cusps of the atrioventricular valves in place and preventing them from being blown back into the atria. The aortic and pulmonary semilunar valves lack the chordae tendineae and papillary muscles associated with the atrioventricular valves. Instead, they consist of pocket-like folds of endocardium reinforced with additional connective tissue. When the ventricles relax and the change in pressure forces the blood toward the ventricles, the blood presses against these cusps and seals the openings. |
What is the skin of most reptiles covered with? | hairs | pores | cuticle | scales | Reptiles have several adaptations for living on dry land that amphibians lack. For example, as shown in Figure below , the skin of most reptiles is covered with scales. The scales are made of very tough keratin, and they protect reptiles from injury, and also prevent them from losing water. |
Gasoline, natural gas, fuel oil, diesel fuel, jet fuel, coal, kerosene, and propane are examples of what type of fule? | nuclear fue | electrolysis fuel | polymerization fuel | hydrocarbon fuel | It is hard to overstate the importance of hydrocarbons to modern life. Hydrocarbons have even been called the “driving force of western civilization. ” You saw some ways they are used in the opening image. Several other ways are pictured in the Figure below . The most important use of hydrocarbons is for fuel. Gasoline, natural gas, fuel oil, diesel fuel, jet fuel, coal, kerosene, and propane are just some of the commonly used hydrocarbon fuels. Hydrocarbons are also used to make things, including plastics and synthetic fabrics such as polyester. |
Nearly all life processes depend on what substance, which is involved in biochemical reactions? | air | food | hydrocarbons | water | Water is involved in many other biochemical reactions. As a result, just about all life processes depend on water. Clearly, life as we know it could not exist without water. |
What has increased in the atmosphere throughout the history of the earth? | carbon | nitrogen | wind | oxygen | Oxygen has increased in the atmosphere throughout the history of the earth. Note the logarithmic scale, which indicates great increases after first photosynthesis (in bacteria) and then land plants evolved. Related geological events: A = no oxidized iron; B = oxidized iron bands in seabed rock - evidence for O 2 in the oceans; C = oxidized iron bands on land and ozone layer formation- evidence for O 2 in the atmosphere. |
Which two states of matter have definite volumes? | contrasts and liquids | bacteria and liquids | GAS AND LIQUIDS | solids and liquids | Ice, water, and steam appear quite differently to the eye. If you were to look at these three states of matter on the molecular level, you would see that the arrangement of molecules is very different here as well. However, solids and liquids have definite volumes, unlike gases which tend to take on the shape of their container. In this lesson, you will learn about the unique behavior of gas particles on a molecular level and the basis for kinetic molecular theory. |
Tendon, cartilage, and bone are examples of what type of tissue that supports and binds other tissues of the body? | repetitive tissue | muscular tissue | untreated tissue | connective tissue | Connective tissue is made up of many different types of cells that are all involved in supporting and binding other tissues of the body. Examples include tendon, cartilage, and bone. Blood is also classified as a specialized connective tissue. |
What is the sac-like organ at the end of the esophagus? | appendix | rectum | larynx | stomach | The stomach is a sac-like organ at the end of the esophagus. It has thick muscular walls. The muscles contract and relax. This moves the food around and helps break it into smaller pieces. Mixing the food around with the enzyme pepsin and other chemicals helps digest proteins. |
Which class of acids acetic acid (ch 3 cooh) belongs to? | common acids | anorganic acids | strong acids | organic acids | Not all hydrogen atoms in molecular compounds are ionizable. In methane (CH 4 ), the hydrogen atoms are covalently bonded to carbon in bonds that are only slightly polar. The hydrogen atoms are not capable of ionizing and methane has no acidic properties. Acetic acid (CH 3 COOH) belongs to a class of acids called organic acids. There are four hydrogen atoms in the molecule, but only the one hydrogen that is bonded to an oxygen atom is ionizable. |
What happens to the total energy of the system when heat is positive? | it decreases | nothing | it remains constant | it increases | When heat is positive, the total energy of the system is increasing. |
What type of species can alternate between medusa and polyp forms? | chordata | mollusks | crocodilian | cnidarian | As you can see in Figure below , both body plans have radial symmetry. Some cnidarian species alternate between medusa and polyp forms. Other species exist in just one form or the other. |
Extensive and intensive are categories of properties that apply to what? | height | volume | weight | matter | Properties of matter fall into one of two categories. If the property depends on the amount of matter present, it is an extensive property. The mass and volume of a substance are examples of extensive properties; for instance, a gallon of milk has a larger mass and volume than a cup of milk. The value of an extensive property is directly proportional to the amount of matter in question. If the property of a sample of matter does not depend on the amount of matter present, it is an intensive property. Temperature is an example of an intensive property. If the gallon and cup of milk are each at 20 °C (room temperature), when they are combined, the temperature remains at 20 °C. As another example, consider the distinct but related properties of heat and temperature. A drop of hot cooking oil spattered on your arm causes brief, minor discomfort, whereas a pot of hot oil yields severe burns. Both the drop and the pot of oil are at the same temperature (an intensive property), but the pot clearly contains much more heat (extensive property). |
The vertebrate circulatory system enables blood to deliver ________ and remove wastes throughout the body. | fluid and nutrients | hydrogen and nutrients | acid and nutrients | oxygen and nutrients | |
By what kind of change can a chemical change be reversed? | another radioactive change | another carbon change | another thermal change | another chemical change | Because chemical changes result in different substances, they often cannot be undone. Some chemical changes can be reversed, but only by other chemical changes. |
Earthquakes at convergent plate boundaries mark the location of the what? | shorting lithosphere | abducting lithosphere | speeding lithosphere | subducting lithosphere | Earthquakes at convergent plate boundaries mark the location of the subducting lithosphere. The motion of the lithosphere as it plunges through the mantle causes the quakes ( Figure below ). At greater depths, the plate heats up enough to deform plastically. |
New seafloor forms when what object cools? | rain | ash | debris | lava | The seafloor spreading hypothesis brought all of these observations together in the early 1960s. Hot mantle material rises up at mid-ocean ridges. The hot magma erupts as lava. The lava cools to form new seafloor. Later, more lava erupts at the ridge. The new lava pushes the seafloor that is at the ridge horizontally away from ridge axis. The seafloor moves!. |
What are groups of atoms that behave as a single unit called? | ions | protons | particles | molecules | Molecules are groups of atoms that behave as a single unit. |
Hormones cause cellular changes by binding to receptors on these? | reach cells | able cells | fighter cells | target cells | 37.2 How Hormones Work Hormones cause cellular changes by binding to receptors on target cells. The number of receptors on a target cell can increase or decrease in response to hormone activity. Hormones can affect cells directly through intracellular hormone receptors or indirectly through plasma membrane hormone receptors. Lipid-derived (soluble) hormones can enter the cell by diffusing across the plasma membrane and binding to DNA to regulate gene transcription and to change the cell’s activities by inducing production of proteins that affect, in general, the long-term structure and function of the cell. Lipid insoluble hormones bind to receptors on the plasma membrane surface and trigger a signaling pathway to change the cell’s activities by inducing production of various cell products that affect the cell in the short-term. The hormone is called a first messenger and the cellular component is called a second messenger. G-proteins activate the second messenger (cyclic AMP), triggering the cellular response. Response to hormone binding is amplified as the signaling pathway progresses. Cellular responses to hormones include the production of proteins and enzymes and altered membrane permeability. |
Food provides what type of energy needed by organisms, which is stored in bonds? | calories | radiation energy | caffeine | chemical energy | The chemical energy that organisms need comes from food. Food consists of organic molecules that store energy in their chemical bonds. In terms of obtaining food for energy, there are two types of organisms: autotrophs and heterotrophs. |
Catabolic reactions involve breaking what? | metals | molecules | levels | bonds | Catabolic reactions involve breaking bonds. Larger molecules break down to form smaller ones. These reactions release energy. For example, energy is released when starches break down to sugars. |
Scientists explain the world based on what? | theories | changes | patterns | observations | Such knowledge of the natural world is only part of what science is. Science is as much about doing as knowing. Science is a way of learning about the natural world that depends on evidence, reasoning, and repeated testing. Scientists explain the world based on their observations. If they develop new ideas about the way the world works, they set up ways to test these new ideas. Scientific knowledge keeps changing because scientists are always “doing science. ”. |
What is the general name for saturated hydrocarbons? | halides | petrolatums | enzymes | alkanes | Saturated hydrocarbons are given the general name of alkanes . The name of specific alkanes always ends in - ane . The first part of the name indicates how many carbon atoms each molecule of the alkane has. The smallest alkane is methane. It has just one carbon atom. The next largest is ethane, with two carbon atoms. The chemical formulas and properties of methane, ethane, and several other alkanes are listed in Table below . The boiling and melting points of alkanes are determined mainly by the number of carbon atoms they have. Alkanes with more carbon atoms generally have higher boiling and melting points. |
Changing electric and mnagnetic fields radiate outward when? | firing particles accelerate | particles lose their charge | particles multiply | charged particles accelerate | When charged particles accelerate , changing electric and magnetic fields radiate outward. The traveling electric and magnetic fields of an accelerating (often oscillating) charged particle are known as electromagnetic radiation or light. |
What significant part of the cell do prokaryotic cells lack? | mitochondrial dna | a cell wall | a ribosome | a nucleus | Prokaryotic cells are cells that lack a nucleus. The DNA in prokaryotic cells is in the cytoplasm, rather than enclosed within a nuclear membrane. All the organisms in the Bacteria and Archaea Domains have prokaryotic cells. No other organisms have this type of cell. Organisms with prokaryotic cells are called prokaryotes . They are all single-celled organisms. They were the first type of organisms to evolve. They are still the most numerous organisms today. |
Where do ectotherms get most of their heat? | internally | food | metabolism | external sources | |
What layer is above the mesosphere? | ionosphere | exosphere | stratosphere | thermosphere | The thermosphere is the layer above the mesosphere. It rises to 600 kilometers (372 miles) above the surface. The International Space Station orbits Earth in this layer as in Figure below . |
What is produced by leydig cells in the embryonic testis and stimulates the development of male sexual organs? | estrogen | androgen | insulin | testosterone | 27.3 Development of the Male and Female Reproductive Systems The reproductive systems of males and females begin to develop soon after conception. A gene on the male’s Y chromosome called SRY is critical in stimulating a cascade of events that simultaneously stimulate testis development and repress the development of female structures. Testosterone produced by Leydig cells in the embryonic testis stimulates the development of male sexual organs. If testosterone is not present, female sexual organs will develop. Whereas the gonads and some other reproductive tissues are considered bipotential, the tissue that forms the internal reproductive structures stems from ducts that will develop into only male (Wolffian) or female (Müllerian) structures. To be able to reproduce as an adult, one of these systems must develop properly and the other must degrade. Further development of the reproductive systems occurs at puberty. The initiation of the changes that occur in puberty is the result of a decrease in sensitivity to negative feedback in the hypothalamus and pituitary gland, and an increase in sensitivity of the gonads to FSH and LH stimulation. These changes lead to increases in either estrogen or testosterone, in female and male adolescents, respectively. The increase in sex steroid hormones leads to maturation of the gonads and other reproductive organs. The initiation of spermatogenesis begins in boys, and girls begin ovulating and menstruating. Increases in sex steroid hormones also lead to the development of secondary sex characteristics such as breast development in girls and facial hair and larynx growth in boys. |
What is a continuous flow of electric charges called? | circuit | electricity | magnetic current | electric current | Electric current is a continuous flow of electric charges. Current is measured as the amount of charge that flows past a given point in a certain amount of time. The SI unit for electric current is the ampere (A), or amp. Electric current may flow in just one direction, or it may keep reversing direction. |
What causes high winds and monsoon storms in the desert? | low winter temperature | moderate spring temperature | and-12 summer temperature | high summer temperature | High summer temperatures on the desert create high winds and monsoon storms. Strong winds in the desert can pick up dust and blow it around. A dust storm known as a haboob ( Figure below ) forms in the downdrafts on the front of a thunderstorm. |
What are the three most common protective devices? | fuses , fabrication breaks & surge protectors | fuses , circuit breaks & surge claws | tranistors, resistors & diodes | fuses, circuit breaks & surge protectors | There are multiple ways to prevent these situations from occurring. The three most common protective devices are fuses, circuit breakers, and surge protectors. |
Which veins return oxygen-rich blood from the lungs to the heart? | respiratory | jugular | varicose | pulmonary | Today in many countries, death rates have gone down but birth rates remain high. This means that the population is growing. Figure below shows the growth rates of human populations all over the world. |
Makemake and pluto are classified as what type of celestial object? | gas giants | nebula | black holes | dwarf planets | Makemake is the third-largest and second-brightest dwarf planet we have discovered so far ( Figure below ). Makemake is only 75 percent the size of Pluto. Its diameter is between 1300 and 1900 kilometers. The name comes from the mythology of the Eastern Islanders. Makemake was the god that created humanity. At a distance between 38.5 to 53 AU, this dwarf planet orbits the Sun in 310 years. Makemake is made of methane, ethane, and nitrogen ices. |
What do you call the entire range of wavelengths of electromagnetic waves? | molecular spectrum | electric spectrum | gaseous spectrum | electromagnetic spectrum | Sunlight contains the complete range of wavelengths of electromagnetic waves. The entire range is called the electromagnetic spectrum. |
Joules and calories are the units of what? | heat and velocity | weight and energy | mass and potential | energy and heat | Joules and calories are the units of energy and heat. |
The brain and spinal cord are part of what system? | immune system | cardiovascular system | digestive system | central nervous system | The brain and spinal cord make up the central nervous system. |
The two parathyroid glands are located behind what gland? | hypothalmus | thymus | pituitary gland | thyroid | The two parathyroid glands are located behind the thyroid gland. Parathyroid hormone helps keep the level of calcium in the blood within a narrow range. It stimulates bone cells to dissolve calcium in bone matrix and release it into the blood. |
Fission is a method of what type of reproduction exhibited by some planarians? | propagation | spawning | sexual | asexual | |
The best method for preparing pure phosphorous acid is by hydrolyzing what? | dioxide phosphat | dioxide trichloride | carbon trichloride | phosphorus trichloride | Dilution of the products with water, followed by filtration to remove calcium sulfate, gives a dilute acid solution contaminated with calcium dihydrogen phosphate, Ca(H2PO4)2, and other compounds associated with calcium phosphate rock. It is possible to prepare pure orthophosphoric acid by dissolving P4O10 in water. The action of water on P4O6, PCl3, PBr3, or PI3 forms phosphorous acid, H3PO3 (shown in Figure 18.53). The best method for preparing pure phosphorous acid is by hydrolyzing phosphorus trichloride: PCl 3(l) + 3H 2 O(l) ⟶ H 3 PO 3(aq) + 3HCl(g) Heating the resulting solution expels the hydrogen chloride and leads to the evaporation of water. When sufficient water evaporates, white crystals of phosphorous acid will appear upon cooling. The crystals are deliquescent, very soluble in water, and have an odor like that of garlic. The solid melts at 70.1 °C and decomposes at about 200 °C by disproportionation into phosphine and orthophosphoric acid: 4H 3 PO 3(l) ⟶ PH 3(g) + 3H 3 PO 4(l). |
What bonds result from the overlap of atomic orbitals? | metallic | valent | hydrogen | covalents | Covalent bonds result from the overlap of atomic orbitals. |
What is a cluster of neuron cell bodies in the pns called? | crystals | groupilion | gangnem | ganglion | Regardless of the appearance of stained or unstained tissue, the cell bodies of neurons or axons can be located in discrete anatomical structures that need to be named. Those names are specific to whether the structure is central or peripheral. A localized collection of neuron cell bodies in the CNS is referred to as a nucleus. In the PNS, a cluster of neuron cell bodies is referred to as a ganglion. Figure 12.4 indicates how the term nucleus has a few different meanings within anatomy and physiology. It is the center of an atom, where protons and neutrons are found; it is the center of a cell, where the DNA is found; and it is a center of some function in the CNS. There is also a potentially confusing use of the word ganglion (plural = ganglia) that has a historical explanation. In the central nervous system, there is a group of nuclei that are connected together and were once called the basal ganglia before “ganglion” became accepted as a description for a peripheral structure. Some sources refer to this group of nuclei as the “basal nuclei” to avoid confusion. |
Unlike the passive form, the sodium-potassium pump uses what type of transport? | phase | High | Low | active | Mariana Ruiz Villarreal (User:LadyofHats/Wikimedia Commons), modified by Hana Zavadska. The sodium-potassium pump uses active transport . Public Domain. |
On insects, what are the openings on the sides of the abdomen that allows respiration to occur? | chloroplasts | gills | wings | spiracles | Respiration that occurs without lungs. Insects have a system of internal tubes and sacs that oxygen travels through to reach body tissues. Air is taken in through the spiracles , openings on the sides of the abdomen. |
Salts of weak acids or bases can affect the acidity or what of their aqueous solution? | ductility | atomicity | compound | basicity | Salts of weak acids or bases can affect the acidity or basicity of their aqueous solutions. |
Flowers, double fertilization, and fruits are unique features of what life cycle? | early lifehood | dinoflagellate | protozoa | angiosperm | 38.1 Flowers, double fertilization, and fruits are unique features of the angiosperm life cycle. |
What is most often the cause of encephalitis? | calcium buildup | parasites | bacterial infections | viruses | Encephalitis is a brain infection most often caused by viruses. The immune system tries to fight off a brain infection, just as it tries to fight off other infections. But sometimes this can do more harm than good. The immune system’s response may cause swelling in the brain. With no room to expand, the brain pushes against the skull. This may injure the brain and even cause death. Medicines can help fight some viral infections of the brain, but not all infections. |
Why do microwaves have a higher energy than radio waves? | higher decibel | higher resonance | lower frequency | higher frequency | Find the microwave in the Figure above . A microwave is an electromagnetic wave with a relatively long wavelength and low frequency. Microwaves are often classified as radio waves, but they have higher frequencies than other radio waves. With higher frequencies, they also have more energy. That’s why microwaves are useful for heating food in microwave ovens. Microwaves have other important uses as well, including cell phone transmissions and radar. These uses are described below. You can learn more about microwaves and their uses in the video at this URL: http://www. youtube. com/watch?v=YgQQb1BVnu8 . |
What is cytology. | the study of plants | the study of cancers | the study of atomic structure | the study of cell structure | |
When solids change to gasses, they generally pass through what other state? | carbon | chemical | frozen | liquid | Solids that change to gases generally first pass through the liquid state. However, sometimes solids change directly to gases and skip the liquid state. The reverse can also occur. Sometimes gases change directly to solids. |
What is the structure which hangs from a newly hatched salmon larva? | stomach sac | air sac | liquid sac | yolk sac | Salmon Larva. This newly hatched salmon larva doesn’t look very fish-like. The structure hanging from the larva is the yolk sac. |
What is made up of the pinna, ear canal, and eardrum? | the nervous system | the epidermis | the inner ear | the outer ear | The outer ear includes the pinna, ear canal, and eardrum. These structures gather sound waves, funnel them into the ear, and pass the vibrations to the middle ear. |
What type of solvents is glucose insoluble in? | acidic | alkaline | polar | nonpolar | The same principles govern the solubilities of molecular solids in liquids. For example, elemental sulfur is a solid consisting of cyclic S8 molecules that have no dipole moment. Because the S8 rings in solid sulfur are held to other rings by London dispersion forces, elemental sulfur is insoluble in water. It is, however, soluble in nonpolar solvents that have comparable London dispersion forces, such as CS2 (23 g/100 mL). In contrast, glucose contains five –OH groups that can form hydrogen bonds. Consequently, glucose is very soluble in water (91 g/120 mL of water) but essentially insoluble in nonpolar solvents such as benzene. The structure of one isomer of glucose is shown here. |
What organ is divided into the duodenum, the jejunum, and the ileum? | lung | large intestine | kidney | small intestine | Most chemical digestion and nearly all absorption of nutrients take place in the small intestine. This organ consists of three parts: duodenum, jejunum, and ileum. |
Ectotherms undergo a variety of changes at the cellular level to acclimatize to shifts in what? | air pressure | precipitation | oxygen | temperature | |
A comet striking the earth may have caused mass extinction, this would have decreased sunlight, which would have effected what plant process reducing food? | glycolysis | fertilization | decomposition | photosynthesis | At the end of the Cretaceous Period, or 65 million years ago, all dinosaurs (except those which led to birds) went extinct. Some scientists believe a possible cause is a collision between the Earth and a comet or asteroid. The collision could have caused tidal waves, changed the climate, and reduced sunlight by 10-20%. A decrease in photosynthesis would have resulted in less plant food, leading to the extinction of the dinosaurs. |
Normal body temperature is ideal for most of what type of reactions? | theoretical | gas | plasma | biochemical | Biochemical reactions are optimal at physiological temperatures. For example, most biochemical reactions work best at the normal body temperature of 98.6˚F. Many enzymes lose function at lower and higher temperatures. At higher temperatures, an enzyme’s shape deteriorates. Only when the temperature comes back to normal does the enzyme regain its shape and normal activity. |
What separates and strongly unites bodies of adjacent vertebrae? | interstitial fluid | synovial fluid | collagen fibers | intervertebral disc | General Structure of a Vertebra Within the different regions of the vertebral column, vertebrae vary in size and shape, but they all follow a similar structural pattern. A typical vertebra will consist of a body, a vertebral arch, and seven processes (Figure 7.23). The body is the anterior portion of each vertebra and is the part that supports the body weight. Because of this, the vertebral bodies progressively increase in size and thickness going down the vertebral column. The bodies of adjacent vertebrae are separated and strongly united by an intervertebral disc. The vertebral arch forms the posterior portion of each vertebra. It consists of four parts, the right and left pedicles and the right and left laminae. Each pedicle forms one of the lateral sides of the vertebral arch. The pedicles are anchored to the posterior side of the vertebral body. Each lamina forms part of the posterior roof of the vertebral arch. The large opening between the vertebral arch and body is the vertebral foramen, which contains the spinal cord. In the intact vertebral column, the vertebral foramina of all of the vertebrae align to form the vertebral (spinal) canal, which serves as the bony protection and passageway for the spinal cord down the back. When the vertebrae are aligned together in the vertebral column, notches in the margins of the pedicles of adjacent vertebrae together form an intervertebral foramen, the opening through which a spinal nerve exits from the vertebral column (Figure 7.24). |
About 20 percent of carbon dioxide is bound by hemoglobin and is transported where? | bones | brain tissues | intestines | lungs | Carbaminohemoglobin About 20 percent of carbon dioxide is bound by hemoglobin and is transported to the lungs. Carbon dioxide does not bind to iron as oxygen does; instead, carbon dioxide binds amino acid moieties on the globin portions of hemoglobin to form carbaminohemoglobin, which forms when hemoglobin and carbon dioxide bind. When hemoglobin is not transporting oxygen, it tends to have a bluish-purple tone to it, creating the darker maroon color typical of deoxygenated blood. The following formula depicts this reversible reaction:. |
Which outermost secondary xylem layers transport water? | the narrowest | the farthest | the oldest | the youngest | |
What did volcanic gases help to form on earth? | rocks | water | plants | atmosphere | When Earth first formed, it was a fiery hot, barren ball. It had no oceans or atmosphere. Rivers of melted rock flowed over its surface. Gradually, the planet cooled and formed a solid crust. Gases from volcanoes formed an atmosphere, although it contained only a trace of oxygen. As the planet continued to cool, clouds formed and rain fell. Rainwater helped form oceans. The ancient atmosphere and oceans would be toxic to modern life, but they set the stage for life to begin. |
What is formed when the ceiling of an underground cave collapses? | mountain | hill | groundwater | sinkhole | As erosion by groundwater continues, the ceiling of a cave may collapse. The rock and soil above it sink into the ground. This forms a sinkhole on the surface. You can see an example of a sinkhole in Figure below . Some sinkholes are big enough to swallow vehicles and buildings. |
What type of muscle makes up most of the heart? | respiratory muscle | chest muscles | heart muscle | cardiac muscle | The heart is a muscular organ in the chest that consists mainly of cardiac muscle. It pumps blood through blood vessels by repeated, rhythmic contractions. Blood flows through four chambers of the heart when it beats. Heartbeat is controlled by electrical signals from special cells within the heart called the pacemaker. |
What measures the amount of water in the air? | fire index | cloud cover | temperature | humidity | Humidity is the amount of water in the air. Air with a high concentration of water will be called humid. Moving away from the most humid climate, biomes will be called semi-humid, semi-arid, or arid (the driest). |
Most terrestrial vertebrates have what type of lungs? | mechanical | extra | external | internal | |
What process joins two haploid gametes into a diploid zygote? | migration | embryo | fusion | fertilization | Fertilization joins two haploid gametes into a diploid zygote. |
Planets are held by the force of gravity in elliptical orbits around what? | jupitor | earth | mars | sun | Planets are held by the force of gravity in elliptical orbits around the Sun. |
What is the fastest land animal? | greyhound | ostrich | rhino | cheetah | Mammals are noted for the many ways they can move. Some mammals are well known for their speed. The fastest land animal is a mammal, the cheetah. It can race at speeds of up to 112 kilometers (70 miles) per hour. |
What is the process by which the remains of living things become fossils? | petrification | decomposition | sublimation | fossilization | The process by which remains or traces of living things become fossils is called fossilization . Most fossils are preserved in sedimentary rocks. |
Meters, such as those in analog fuel gauges on a car, are a common application of magnetic torque on a current-carrying what? | arc | circuit | dial | loop | Meters, such as those in analog fuel gauges on a car, are another common application of magnetic torque on a current-carrying loop. Figure 22.37 shows that a meter is very similar in construction to a motor. The meter in the figure has its magnets shaped to limit the effect of θ by making B perpendicular to the loop over a large angular range. Thus the torque is proportional to I and not. |
What causes reduction of elasticity in all organs? | weight gain | low vitamin D | radiation | age | Unlike bones and tendons, which need to be strong as well as elastic, the arteries and lungs need to be very stretchable. The elastic properties of the arteries are essential for blood flow. The pressure in the arteries increases and arterial walls stretch when the blood is pumped out of the heart. When the aortic valve shuts, the pressure in the arteries drops and the arterial walls relax to maintain the blood flow. When you feel your pulse, you are feeling exactly this—the elastic behavior of the arteries as the blood gushes through with each pump of the heart. If the arteries were rigid, you would not feel a pulse. The heart is also an organ with special elastic properties. The lungs expand with muscular effort when we breathe in but relax freely and elastically when we breathe out. Our skins are particularly elastic, especially for the young. A young person can go from 100 kg to 60 kg with no visible sag in their skins. The elasticity of all organs reduces with age. Gradual physiological aging through reduction in elasticity starts in the early 20s. |
How many protons and electrons each do carbon atoms have? | five | two | nine | six | Consider carbon as an example. Carbon atoms have six protons. They also have six electrons. All carbon atoms are the same whether they are found in a lump of coal or a teaspoon of table sugar ( Figure below ). On the other hand, carbon atoms are different from the atoms of hydrogen, which are also found in coal and sugar. Each hydrogen atom has just one proton and one electron. |
What thickens the cortex around the inner edge of a cell? | plasma membrane | mitochondria | vacuoles | microfilaments | Figure 4.22 Microfilaments thicken the cortex around the inner edge of a cell; like rubber bands, they resist tension. Microtubules are found in the interior of the cell where they maintain cell shape by resisting compressive forces. Intermediate filaments are found throughout the cell and hold organelles in place. |
What value of dissolved substances is higher than that of their corresponding precipitate? | ordiny | negentropy | binary | entropy | Dissolved substances have a higher entropy value than their corresponding precipitate. |
Is an acid lower or higher than 7 on the ph scale? | twice as much as 7 | exactly 7 | higher than 7 | lower than 7 | A: The weakest acid on the scale is milk, which has a pH value between 6.5 and 6.8. The strongest base on the scale is liquid drain cleaner, which has a pH of 14. |
Although what biochemicals circulate throughout the body and come into contact with many different cell types, they only affect cells that possess the necessary receptors? | enzymes | Cells | organs | hormones | How Hormones Work Hormones cause changes in target cells by binding to specific cell-surface or intracellular hormone receptors, molecules embedded in the cell membrane or floating in the cytoplasm with a binding site that matches a binding site on the hormone molecule. In this way, even though hormones circulate throughout the body and come into contact with many different cell types, they only affect cells that possess the necessary receptors. Receptors for a specific hormone may be found on or in many different cells or may be limited to a small number of specialized cells. For example, thyroid hormones act on many different tissue types, stimulating metabolic activity throughout the body. Cells can have many receptors for the. |
The right atrium receives all of the systemic venous return. most of the blood flows into either the superior vena cava or this? | exterior vena cava | resulted vena cava | identical vena cava | inferior vena cava | The right atrium receives all of the systemic venous return. Most of the blood flows into either the superior vena cava or inferior vena cava. If you draw an imaginary line at the level of the diaphragm, systemic venous circulation from above that line will generally flow into the superior vena cava; this includes blood from the head, neck, chest, shoulders, and upper limbs. The exception to this is that most venous blood flow from the coronary veins flows directly into the coronary sinus and from there directly into the right atrium. Beneath the diaphragm, systemic venous flow enters the inferior vena cava, that is, blood from the abdominal and pelvic regions and the lower limbs. |
Tissue is made up of layers of tightly packed cells that line the surfaces of the body, such as skin. | resultant tissue | weak tissue | neural tissue | epithelial tissue | Epithelial tissue is made up of layers of tightly packed cells that line the surfaces of the body. Examples of epithelial tissue include the skin, the lining of the mouth and nose, and the lining of the digestive system. |
Most lipid hormones are derived from what? | fat | protein | tissue | cholesterol | Lipid-Derived Hormones (or Lipid-soluble Hormones) Most lipid hormones are derived from cholesterol and thus are structurally similar to it, as illustrated in Figure 37.2. The primary class of lipid hormones in humans is the steroid hormones. Chemically, these hormones are usually ketones or alcohols; their chemical names will end in “-ol” for alcohols or “-one” for ketones. Examples of steroid hormones include estradiol, which is an estrogen, or female sex hormone, and testosterone, which is an androgen, or male sex hormone. These two hormones are released by the female and male reproductive organs, respectively. Other steroid hormones include aldosterone and cortisol, which are released by the adrenal glands along with some other types of androgens. Steroid hormones are insoluble in water, and they are transported by transport proteins in blood. As a result, they remain in circulation longer than peptide hormones. For example, cortisol has a half-life of 60 to 90 minutes, while epinephrine, an amino acid derived-hormone, has a half-life of approximately one minute. |
A fact or question is only considered science if it has what property? | it is believable | it is interesting | it is mineral | it is testable | Note the word science in that last sentence. Earth Science is a science, or maybe it’s made up of a lot of sciences. But what is science? Most people think of science as a bunch of knowledge. And it is. But science is also a way of knowing things. It’s different from other ways of knowing because it is based on a method that relies on observations and data. Science can’t say how many angels can dance on the end of a pin because that question can’t be tested. In fact, science can’t even say if there are such things as angels for the same reason. For something to be science, it must be testable. And scientists are the people who do those tests. |
Which branch of science is the study of energy, matter, and their interactions? | meteorology | geology | biology | physics | Physics is the study of energy, matter, and their interactions. It is concerned with matter and energy at all levels—from the most fundamental particles of matter to the entire universe. |
What is the smallest unit capable of life known as? | insect | living thing | organism | a cell | It could easily be said that a cell is the fundamental unit of life, the smallest unit capable of life or the structural and functional unit necessary for life. But whatever it is, a cell is necessary for life. And as shown above, a cell may be filled with all sorts of structures, each with its own specific function. This concept will discuss some of the fundamental properties of the cell, with lessons that include the cell structure, transport in and out of the cell, energy metabolism, and cell division and reproduction. |
Making associations between experiences is often a part of what activity? | sleeping | dying | eating | learning | |
The spectrum is made up of discrete lines representing transitions of the hydrogen electron between specific energy levels within what? | the molecule | a rainbow | an element | the atom | The emission spectrum of hydrogen is discontinuous. The spectrum is made up of discrete lines representing transitions of the hydrogen electron between specific energy levels within the atom. |
In the field of biodiversity, "richness" and "abundance" are used to describe different what? | water sources | nutrients | densities | species | Biodiversity, Species Richness, and Relative Species Abundance Biodiversity describes a community’s biological complexity: it is measured by the number of different species (species richness) in a particular area and their relative abundance (species evenness). The area in question could be a habitat, a biome, or the entire biosphere. Species richness is the term that is used to describe the number of species living in a habitat or biome. Species richness varies across the globe (Figure 45.29). One factor in determining species richness is latitude, with the greatest species richness occurring in ecosystems near the equator, which often have warmer temperatures, large amounts of rainfall, and low seasonality. The lowest species richness occurs near the poles, which are much colder, drier, and thus less conducive to life in Geologic time (time since glaciations). The predictability of climate or productivity is also an important factor. Other factors influence species richness as well. For example, the study of island biogeography attempts to explain the relatively high species richness found in certain isolated island chains, including the Galápagos Islands that inspired the young Darwin. Relative species abundance is the number of individuals in a species relative to the total number of individuals in all species within a habitat, ecosystem, or biome. Foundation species often have the highest relative abundance of species. |
Nitrogen is an important macronutrient because it is part of nucleic acids and proteins. atmospheric nitrogen, which is the diatomic molecule n2, or dinitrogen, is the largest pool of nitrogen in these? | aquatic ecosytems | gas planets | desert biomes | terrestrial ecosystems | Nitrogen Fixation: Root and Bacteria Interactions Nitrogen is an important macronutrient because it is part of nucleic acids and proteins. Atmospheric nitrogen, which is the diatomic molecule N2, or dinitrogen, is the largest pool of nitrogen in terrestrial ecosystems. However, plants cannot take advantage of this nitrogen because they do not have the necessary enzymes to convert it into biologically useful forms. However, nitrogen can be “fixed,” which means that it can be converted to ammonia (NH3) through biological, physical, or chemical processes. As you have learned, biological nitrogen fixation (BNF) is the conversion of atmospheric nitrogen (N2) into ammonia (NH3), exclusively carried out by prokaryotes such as soil bacteria or cyanobacteria. Biological processes contribute 65 percent of the nitrogen used in agriculture. The following equation represents the process:. |
What is the term for rotation of a bone toward the midline of the body? | lateral rotation | visual rotation | interior rotation | medial rotation | Rotational Movement Rotational movement is the movement of a bone as it rotates around its longitudinal axis. Rotation can be toward the midline of the body, which is referred to as medial rotation, or away from the midline of the body, which is referred to as lateral rotation. Movement of the head from side to side is an example of rotation. Special Movements Some movements that cannot be classified as gliding, angular, or rotational are called special movements. Inversion involves the soles of the feet moving inward, toward the midline of the body. Eversion is the opposite of inversion, movement of the sole of the foot outward, away from the midline of the body. Protraction is the anterior movement of a bone in the horizontal plane. Retraction occurs as a joint moves back into position after protraction. Protraction and retraction can be seen in the movement of the mandible as the jaw is thrust outwards and then back inwards. Elevation is the movement of a bone upward, such as when the shoulders are shrugged, lifting the scapulae. Depression is the opposite of elevation—movement downward of a bone, such as after the shoulders are shrugged and the scapulae return to their normal position from an elevated position. Dorsiflexion is a bending at the ankle such that the toes are lifted toward the knee. Plantar flexion is a bending at the ankle when the heel is lifted, such as when standing on the toes. Supination is the movement of the radius and ulna bones of the forearm so that the palm faces forward. Pronation is the opposite movement, in which the palm faces backward. Opposition is the movement of the thumb toward the fingers of the same hand, making it possible to grasp and hold objects. |
What cause rabies, measles, diarrheal diseases, hepatitis, polio, and cold sores? | contaminants | parasites | bacteria | viruses | Viruses cause many human diseases. In addition to the diseases mentioned above, viruses cause rabies, measles, diarrheal diseases, hepatitis, polio, and cold sores (see Figure below ). Viral diseases range from mild to fatal. One way viruses cause disease is by causing host cells to burst open and die. Viruses may also cause disease without killing host cells. They may cause illness by disrupting homeostasis in host cells. |
What are the two methods in which mutations arise in dna? | accelerated or random | produced or spontaneous | accelerated or spontaneous | induced or spontaneous | Errors during DNA replication are not the only reason why mutations arise in DNA. Mutations, variations in the nucleotide sequence of a genome, can also occur because of damage to DNA. Such mutations may be of two types: induced or spontaneous. Induced mutations are those that result from an exposure to chemicals, UV rays, x-rays, or some other environmental agent. Spontaneous mutations occur without any exposure to any environmental agent; they are a result of natural reactions taking place within the body. Mutations may have a wide range of effects. Some mutations are not expressed; these are known as silent mutations. Point mutations are those mutations that affect a single base pair. The most common nucleotide mutations are substitutions, in which one base is replaced by another. These can be of two types, either transitions or transversions. Transition substitution refers to a purine or pyrimidine being replaced by a base of the same kind; for example, a purine such as adenine may be replaced by the purine guanine. Transversion substitution refers to a purine being replaced by a pyrimidine, or vice versa; for example, cytosine, a pyrimidine, is replaced by adenine, a purine. Mutations can also be the result of the addition of a base, known as an insertion, or the removal of a base, also known as deletion. Sometimes a piece of DNA from one chromosome may get translocated to another chromosome or to another region of the same chromosome; this is also known as translocation. These mutation types are shown in Figure 14.21. |
Water follows where sodium ions lead, due to what process? | hydration | electrolysis | absorption | osmosis | Blood Pressure Regulation Due to osmosis, water follows where Na+ leads. Much of the water the kidneys recover from the forming urine follows the reabsorption of Na+. ADH stimulation of aquaporin channels allows for regulation of water recovery in the collecting ducts. Normally, all of the glucose is recovered, but loss of glucose control (diabetes mellitus) may result in an osmotic dieresis severe enough to produce severe dehydration and death. A loss of renal function means a loss of effective vascular volume control, leading to hypotension (low blood pressure) or hypertension (high blood pressure), which can lead to stroke, heart attack, and aneurysm formation. The kidneys cooperate with the lungs, liver, and adrenal cortex through the renin–angiotensin–aldosterone system (see Figure 25.14). The liver synthesizes and secretes the inactive precursor angiotensinogen. When the blood pressure is low, the kidney synthesizes and releases renin. Renin converts angiotensinogen into angiotensin I, and ACE produced in the lung converts angiotensin I into biologically active angiotensin II (Figure 25.23). The immediate and short-term effect of angiotensin II is to raise blood pressure by causing widespread vasoconstriction. angiotensin II also stimulates the adrenal. |
What group of simple organisms recycles nutrients and has been on earth since long before multicellular life appeared? | eukaryotes | bacteria | protists | prokaryotes | 22.1 | Prokaryotic Diversity By the end of this section, you will be able to: • Describe the evolutionary history of prokaryotes • Discuss the distinguishing features of extremophiles • Explain why it is difficult to culture prokaryotes Prokaryotes are ubiquitous. They cover every imaginable surface where there is sufficient moisture, and they live on and inside of other living things. In the typical human body, prokaryotic cells outnumber human body cells by about ten to one. They comprise the majority of living things in all ecosystems. Some prokaryotes thrive in environments that are inhospitable for most living things. Prokaryotes recycle nutrients—essential substances (such as carbon and nitrogen)—and they drive the evolution of new ecosystems, some of which are natural and others man-made. Prokaryotes have been on Earth since long before multicellular life appeared. |
What is the term for dry climate regions at higher altitudes that have short grasses and low bushes? | prairie | deserts | fringes | steppes | Other dry climates get a little more precipitation. They are called steppes . These regions have short grasses and low bushes (see Figure below ). Steppes occur at higher latitudes than deserts. They are dry because they are in continental interiors or rain shadows. |