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In a chemical reaction, the amounts of reactants and products will be constant when what state is attained? | homogeneity | saturation | peak | equilibrium | The amount of reactants and products do not have to be equal. However, after equilibrium is attained, the amounts of reactants and products will be constant. |
What protects a developing flower while it is still a bud? | lobes | shell | petals | sepals | Sepals protect the developing flower while it is still a bud. Sepals are usually green, which camouflages the bud from possible consumers. |
What is the term for the force of attraction between things that have a mass? | magnetism | weight | motion | gravity | Gravity has traditionally been defined as a force of attraction between things that have mass. According to this conception of gravity, anything that has mass, no matter how small, exerts gravity on other matter. Gravity can act between objects that are not even touching. In fact, gravity can act over very long distances. However, the farther two objects are from each other, the weaker is the force of gravity between them. Less massive objects also have less gravity than more massive objects. |
What are the long, thin protein extensions in most prokaryotic cells called? | neutrons | analyte | cingulum | flagellum | |
Dialysis is a treatment for failure of what organs? | spleen | lungs | liver | kidneys | Kidney failure may be treated with dialysis. |
What preventive measure can protect even young children against diseases such as viral meningitis? | malnutrition | nutrition | surgical intervention | vaccination | Children as young as 2 years of age can be vaccinated against viral meningitis. |
Renal plasma flow equals the blood flow per minute times the what? | hemoglobin | erythrocytes | leukocytes | hematocrit | Renal plasma flow equals the blood flow per minute times the hematocrit. If a person has a hematocrit of 45, then the renal plasma flow is 55 percent. 1050*0.55 = 578 mL plasma/min. |
What does lattice energy of an ionic solid measure the strength of? | electrons | metals | atoms | bonds | Lattice energy of an ionic solid is a measure of the strength of bonds in that ionic compound. |
How many different types of taste can be detected by taste buds? | hundreds | three | two | five | |
What species do humans belong to? | monkeys | homo erectus | hominids | homo sapiens | Homo sapiens is our species. We originated about 200,000 years ago in Africa. Evidence of a spiritual life appears about 32,000 years ago. The evidence includes stone figurines that probably have religious significance ( Figure below ). |
Titration is a method to determine what in acids or bases? | glucose | alkalinity | maturation | concentration | The concentration of an acid or base can be determined by titration. |
How many different amino acids make up proteins. | 30 | 14 | 25 | 20 | There are 20 amino acids that make up proteins. With three bases per codon, there are 64 possible codons. This is more than enough to code for the 20 amino acids plus start and stop signals. You can see how to translate the genetic code in Figure below . Start at the center of the chart for the first base of each three-base codon. Then work your way out from the center for the second and third bases. |
What are sores in the lining of the stomach or duodenum that are usually caused by bacterial infections or acidity? | hernia | lesions | clots | ulcers | Ulcers are sores in the lining of the stomach or duodenum that are usually caused by bacterial infections. They may also be caused by the acidic environment of the stomach. Stomach acids may damage the lining of the stomach. Symptoms typically include abdominal pain and bleeding. You can see how stomach ulcers develop at this link: http://www. youtube. com/watch?v=4bXZRgJ-1fk . |
In some species, what has led to the evolution of alternative male mating behavior and morphology? | sexual process | distributive selection | similar selection | sexual selection | |
What structure is made from dna and protein molecules coiled together? | atoms | bacterium | enzymes | chromosome | As a cell prepares to divide, its DNA first forms one or more structures called chromosomes. A chromosome consists of DNA and protein molecules coiled into a definite shape. Chromosomes are circular in prokaryotes and rodlike in eukaryotes. You can see an example of a human chromosome in Figure below . The rest of the time, DNA looks like a tangled mass of strings. In this form, it would be very difficult to copy and divide. |
What renewable energy source converts energy from the sunlight into electricity? | hydrostatic energy | geophysical energy | geothermal energy | solar energy | Less energy is needed to get renewable energy sources. Solar energy is a good example. Sunlight is everywhere, so no one needs to go out and find it. We don’t have to drill for it or pump it to the surface. We just need to install solar panels like the ones in Figure below and let sunlight strike them. The energy from the sunlight is changed to electricity. The electricity is used to power lights and appliances in the house. So solar energy doesn't have to be transported. |
The radial artery and which artery parallel their namesake bones, giving off smaller branches until they reach the wrist, or carpal region? | biceps | triceps | humerus | ulnar | Arteries Serving the Upper Limbs As the subclavian artery exits the thorax into the axillary region, it is renamed the axillary artery. Although it does branch and supply blood to the region near the head of the humerus (via the humeral circumflex arteries), the majority of the vessel continues into the upper arm, or brachium, and becomes the brachial artery (Figure 20.31). The brachial artery supplies blood to much of the brachial region and divides at the elbow into several smaller branches, including the deep brachial arteries, which provide blood to the posterior surface of the arm, and the ulnar collateral arteries, which supply blood to the region of the elbow. As the brachial artery approaches the coronoid fossa, it bifurcates into the radial and ulnar arteries, which continue into the forearm, or antebrachium. The radial artery and ulnar artery parallel their namesake bones, giving off smaller branches until they reach the wrist, or carpal region. At this level, they fuse to form the superficial and deep palmar arches that supply blood to the hand, as well as the digital arteries that supply blood to the digits. Figure 20.32 shows the distribution of systemic arteries from the heart into the upper limb. Table 20.9 summarizes the arteries serving the upper limbs. |
The bones of the skull are connected by what type of joints? | adjustable | semi-mobile | pivoting | immovable | Immovable joints allow no movement because the bones at these joints are held securely together by dense collagen. The bones of the skull are connected by immovable joints. |
What is the lowest layer of the atmosphere? | lithosphere | ionosphere | chromosphere | troposphere | The troposphere is the lowest layer of the atmosphere. All of the air you breathe is in the troposphere. All of Earth's weather—wind, rain, snow, heat—is in the troposphere. The troposphere is the lowest and most important layer of the atmosphere!. |
What is the name of the type of plant tissue consisting of undifferentiated cells that can continue to divide and differentiate? | bundle sheth cell | cuticle | guard cell | meristem | The key to continued growth and repair of plant cells is meristem . Meristem is a type of plant tissue consisting of undifferentiated cells that can continue to divide and differentiate. Meristem at the tips of roots and stems allows them to grow in length. This is called primary growth. Meristem within and around vascular tissues allows growth in width. This is called secondary growth. |
Phosphate-containing ocean sediments form primarily from the bodies of ocean organisms and from their what? | blood | ancestors | skeletons | excretions | The Phosphorus Cycle Phosphorus is an essential nutrient for living processes; it is a major component of nucleic acids and phospholipids, and, as calcium phosphate, makes up the supportive components of our bones. Phosphorus is often the limiting nutrient (necessary for growth) in aquatic, particularly freshwater, ecosystems. Phosphorus occurs in nature as the phosphate ion (PO43-). In addition to phosphate runoff as a result of human activity, natural surface runoff occurs when it is leached from phosphate-containing rock by weathering, thus sending phosphates into rivers, lakes, and the ocean. This rock has its origins in the ocean. Phosphate-containing ocean sediments form primarily from the bodies of ocean organisms and from their excretions. However, volcanic ash, aerosols, and mineral dust may also be significant phosphate sources. This sediment then is moved to land over geologic time by the uplifting of Earth’s surface. (Figure 20.13) Phosphorus is also reciprocally exchanged between phosphate dissolved in the ocean and marine organisms. The movement of phosphate from the ocean to the land and through the soil is extremely slow, with the average phosphate ion having an oceanic residence time between 20,000 and 100,000 years. |
What does erosion do to pieces of broken rock? | Cancel Them | lead them | Smooth them | moves them | Erosion moves the pieces of broken rock. |
The passing of traits from parents to offspring is done through what? | blood | sperm | egg | dna | Genetics is the study of inheritance. Inheritance is the passing of traits from parents to offspring. How are these traits "passed"? Through DNA, which is the genetic material of all organisms. This concept will focus on genetics, inheritance, and DNA. |
In a glass of sweet tea the sugar is known as the solute and the water is known as what? | calcium | pigment | solid | solvent | If you’re like Tanya in this picture, you prefer your iced tea sweetened with sugar. Sweetened iced tea is a solution in which solid sugar (the solute) is dissolved in cold liquid tea, which is mostly water (the solvent). When you add sugar to tea, particles of water pull apart particles of sugar. The particles of sugar spread throughout the tea, making all of it taste sweet. |
A few earthquakes take place away from plate boundaries, these are called what? | distant earthquakes | outer earthquakes | deformation earthquakes | intraplate earthquakes | The remaining 5% are scattered around other plate boundaries. A few earthquakes take place away from plate boundaries. These are intraplate earthquakes. |
Red litmus paper turns what color when placed in a basic solution? | pink | white | orange | blue | Red litmus paper turns blue when placed in a basic solution. |
The difference between the theoretical half-reaction reduction potential and the actual voltage required is called what? | overcharge | resistance | excess | overpotential | can occur in electrolytic cells by introducing a power supply, which supplies the energy to force the electrons to flow in the nonspontaneous direction. Electrolysis is done in solutions, which contain enough ions so current can flow. If the solution contains only one material, like the electrolysis of molten sodium chloride, it is a simple matter to determine what is oxidized and what is reduced. In more complicated systems, like the electrolysis of aqueous sodium chloride, more than one species can be oxidized or reduced and the standard reduction potentials are used to determine the most likely oxidation (the half-reaction with the largest [most positive] standard reduction potential) and reduction (the half-reaction with the smallest [least positive] standard reduction potential). Sometimes unexpected half-reactions occur because of overpotential. Overpotential is the difference between the theoretical half-reaction reduction potential and the actual voltage required. When present, the applied potential must be increased, making it possible for a different reaction to occur in the electrolytic cell. The total charge, Q, that passes through an electrolytic cell can be expressed as the current (I) multiplied by time (Q = It) or as the moles of electrons (n) multiplied by Faraday’s constant (Q = nF). These relationships can be used to determine things like the amount of material used or generated during electrolysis, how long the reaction must proceed, or what value of the current is required. |
While the egg is developing, other changes are taking place in the uterus. it develops a thick lining that is full of what? | amniotic fluid | large arteries | white blood cells | tiny blood vessels | While the egg is developing, other changes are taking place in the uterus. It develops a thick lining that is full of tiny blood vessels. The lining prepares the uterus to receive a fertilized egg if fertilization actually takes place. |
The neural plate undergoes a series of cell movements where it rolls up and forms a tube called what? | peripheral tube | cell tube | occular tube | neural tube | called growth factors signal some cells at the edge of the ectoderm to become epidermis cells. The remaining cells in the center form the neural plate. If the signaling by growth factors were disrupted, then the entire ectoderm would differentiate into neural tissue. The neural plate undergoes a series of cell movements where it rolls up and forms a tube called the neural tube, as illustrated in Figure 43.28. In further development, the neural tube will give rise to the brain and the spinal cord. |
Due to the __________ nature of the lipids that make up cell membranes, polar molecules (such as water) and ions cannot easily diffuse across the cell membrane. | catalytic | hydrophylic | saturated | hydrophobic | Small nonpolar molecules can easily diffuse across the cell membrane. However, due to the hydrophobic nature of the lipids that make up cell membranes, polar molecules (such as water) and ions cannot do so. Instead, they diffuse across the membrane through transport proteins. A transport protein completely spans the membrane, and allows certain molecules or ions to diffuse across the membrane. Channel proteins, gated channel proteins, and carrier proteins are three types of transport proteins that are involved in facilitated diffusion. |
In what way do all vertebrates reproduce? | biologically | mitosis | asexually | sexually | Vertebrates reproduce sexually, and almost all have separate male and female sexes. Aquatic species generally have external fertilization, whereas terrestrial species usually have internal fertilization. Vertebrates have one of three reproductive strategies, known as ovipary, ovovivipary, or vivipary. |
First, high temperature denatures proteins and does what to cells? | exposes them | finds them | develops them | kills them | |
What term is used to describe a collection of molecules surrounded by a phospholipid bilayer that is capable of reproducing itself? | organism | atom | proteins | cell | A cell membrane is essentially a mixture of phospholipids that form a phospholipid bilayer. One definition of a cell is a collection of molecules surrounded by a phospholipid bilayer that is capable of reproducing itself. The simplest cells are bacteria, which consist of only a single compartment surrounded by a single membrane. Animal and plant cells are much more complex, however, and contain many different kinds of compartments, each surrounded by a membrane and able to carry out specialized tasks. |
By allowing blood levels of a hormone to be regulated within a narrow range, feedback loops contribute to maintaining what state? | consciousness | hypothesis | hibernation | homeostasis | Role of Feedback Loops The contribution of feedback loops to homeostasis will only be briefly reviewed here. Positive feedback loops are characterized by the release of additional hormone in response to an original hormone release. The release of oxytocin during childbirth is a positive feedback loop. The initial release of oxytocin begins to signal the uterine muscles to contract, which pushes the fetus toward the cervix, causing it to stretch. This, in turn, signals the pituitary gland to release more oxytocin, causing labor contractions to intensify. The release of oxytocin decreases after the birth of the child. The more common method of hormone regulation is the negative feedback loop. Negative feedback is characterized by the inhibition of further secretion of a hormone in response to adequate levels of that hormone. This allows blood levels of the hormone to be regulated within a narrow range. An example of a negative feedback loop is the release of glucocorticoid hormones from the adrenal glands, as directed by the hypothalamus and pituitary gland. As glucocorticoid concentrations in the blood rise, the hypothalamus and pituitary gland reduce their signaling to the adrenal glands to prevent additional glucocorticoid secretion (Figure 17.6). |
Collagen fibers, elastic fibers, and reticular fibers comprise what type of tissue? | skin tissue | nucleus tissue | intestine tissue | connective tissue | Connective Tissue Fibers and Ground Substance Three main types of fibers are secreted by fibroblasts: collagen fibers, elastic fibers, and reticular fibers. Collagen fiber is made from fibrous protein subunits linked together to form a long and straight fiber. Collagen fibers, while flexible, have great tensile strength, resist stretching, and give ligaments and tendons their characteristic resilience and strength. These fibers hold connective tissues together, even during the movement of the body. Elastic fiber contains the protein elastin along with lesser amounts of other proteins and glycoproteins. The main property of elastin is that after being stretched or compressed, it will return to its original shape. Elastic fibers are prominent in elastic tissues found in skin and the elastic ligaments of the vertebral column. Reticular fiber is also formed from the same protein subunits as collagen fibers; however, these fibers remain narrow and are arrayed in a branching network. They are found throughout the body, but are most abundant in the reticular tissue of soft organs, such as liver and spleen, where they anchor and provide structural support to the parenchyma (the functional cells, blood vessels, and nerves of the organ). All of these fiber types are embedded in ground substance. Secreted by fibroblasts, ground substance is made of polysaccharides, specifically hyaluronic acid, and proteins. These combine to form a proteoglycan with a protein core and. |
What the name of the disease where some of the alveoli of the lungs fill with fluid so they can no longer exchange gas? | emphysema | leukemia | lung cancer | pneumonia | Pneumonia is a disease in which some of the alveoli of the lungs fill with fluid so they can no longer exchange gas. Symptoms of pneumonia typically include coughing, chest pain, difficulty breathing, and fatigue. Pneumonia may be caused by an infection or an injury to the lungs. |
What occurs when groups from the same species stop mating because of something other than physical or geographic separation? | invasive speciation | extinction | complementary speciation | sympatric speciation | Sympatric speciation occurs when groups from the same species stop mating because of something other than physical or geographic separation. The behavior of two groups that live in the same region is an example of such separation. The separation may be caused by different mating seasons, for example. Sympatric speciation is more difficult to identify. |
What environment do animals with gills live in? | cold | air | underground | water | |
What is the boiling and freezing point of water in celcius? | 212 degrees c and 32 degrees c | 100 degrees c and 32 degrees c | 212 degrees c and 0 degrees c | 100 degrees c and 0 degrees c | Melting and boiling points are somewhat unique identifiers, especially of compounds. In addition to giving some idea as to the identity of the compound, important information can be obtained about the purity of the material. |
What are living things that obtain glucose by eating self feeders called? | viruses | producers | chimeras | heterotrophs | Types of organisms that make glucose by photosynthesis are pictured in Figure below . They include plants, plant-like protists such as algae, and some kinds of bacteria. Living things that make glucose are called autotrophs ("self feeders"). All other living things obtain glucose by eating autotrophs (or organisms that eat autotrophs). These living things are called heterotrophs ("other feeders"). |
Virtually every task performed by living organisms requires this? | metals | solids | mineral | energy | Introduction Virtually every task performed by living organisms requires energy. Energy is needed to perform heavy labor and exercise, but humans also use energy while thinking, and even during sleep. In fact, the living cells of every organism constantly use energy. Nutrients and other molecules are imported into the cell, metabolized (broken down) and possibly synthesized into new molecules, modified if needed, transported around the cell, and possibly distributed to the entire organism. For example, the large proteins that make up muscles are built from smaller molecules imported from dietary amino acids. Complex carbohydrates are broken down into simple sugars that the cell uses for energy. Just as energy is required to both build and demolish a building, energy is required for the synthesis and breakdown of molecules as well as the transport of molecules into and out of cells. In addition, processes such as ingesting and breaking down pathogenic bacteria and viruses, exporting wastes and toxins, and movement of the cell require energy. From where, and in what form, does this energy come? How do living cells obtain energy, and how do they use it? This chapter will discuss different forms of energy and the physical laws that govern energy transfer. This chapter will also describe how cells use energy and replenish it, and how chemical reactions in the cell are performed with great efficiency. |
The binding of what helps eliminate antigens by phagocytosis and complement-mediated lysis | fats | proteins | amino acids | antibodies | |
What muscles are used to pump water over the gills? | muscles and pharynx | pharynx and tonsils | lungs and pharynx | jaws and pharynx | |
Compounds like sodium chloride form structures called what? | hydrocarbons | ions | microorganisms | crystals | Compounds like sodium chloride form structures called crystals. A crystal is a rigid framework of many ions locked together in a repeating pattern. Ions are electrically charged forms of atoms. You can see a crystal of sodium chloride in the Figure below . It is made up of many sodium and chloride ions. |
What are made of long chains consisting almost solely of carbon and hydrogen? | proteins | nucleic acids | enzymes | lipids | Lipids are made of long chains consisting almost solely of carbon and hydrogen. These long chains are called fatty acids. Fatty acids may be saturated or unsaturated. Figure below shows an example of each type of fatty acid. |
When a series of measurements is precise but not what, the error is usually systematic? | color | velocity | length | accurate | 0 .033 g 1 .117 g × 100 = 3 .0% When a series of measurements is precise but not accurate, the error is usually systematic. Systematic errors can be caused by faulty instrumentation or faulty technique. The difference between accuracy and precision is demonstrated in Skill Builder ES7. |
Inserting copies of normal genes into a patient with defective genes is known as? | chromosome treatment | pattern therapy | cloning | gene therapy | treat genetic disorders. For example, copies of a normal gene might be inserted into a patient with a defective gene. This is called gene therapy . Ideally, it can cure a genetic disorder. |
What type of reproduction usually occur during times of environmental stress? | asexual reproduction | internal reproduction | hysterical reproduction | sexual reproduction | |
All forms of energy can be interconverted. three things can change the energy of an object: the transfer of heat, work performed on or by an object, or some combination of what? | cold and energy | temperature and work | humidity and work | heat and work | All forms of energy can be interconverted. Three things can change the energy of an object: the transfer of heat, work performed on or by an object, or some combination of heat and work. |
What science includes many fields of science related to our home planet? | biology | meteorology | zoology | earth science | Earth science includes many fields of science related to our home planet. |
What are alloys that are mostly composed of mercury known as? | compounds | halogens | fillings | amalgams | Alloys that are mostly composed of mercury are known as amalgams . Amalgams often have special properties that stem from the fact that mercury exists as a liquid at room temperature. As a result, metal amalgams are used for a variety of purposes, including dentistry and the extraction of other pure metals such as gold. |
What are made from highly reflective metal that is applied to a curved or flat piece of glass? | prisms | lenses | kaleidoscopes | mirrors | Mirrors are made from highly reflective metal that is applied to a curved or flat piece of glass. Converging mirrors can be used to focus light – headlights, telescopes, satellite TV receivers, and solar cookers all rely on this principle. |
What do ranchers fear will happen if wolves return? | vegetation predation | loss of environment | human predation | livestock predation | |
How many types of surface waves are there? | six | over a hundred | three | two | Surface waves travel along the ground outward from an earthquake’s epicenter. Surface waves are the slowest of all seismic waves. They travel at 2.5 km (1.5 miles) per second. There are two types of surface waves. Love waves move side-to-side, much like a snake. Rayleigh waves produce a rolling motion as they move up and backward ( Figure above ). Surface waves cause objects to fall and rise. They also cause objects to sway back and forth. These motions cause damage to rigid structures during an earthquake. |
What is the rigid layer that is found outside the cell membrane and surrounds the cell? | cell root | cell barrier | cell shield | cell wall | A cell wall is a rigid layer that is found outside the cell membrane and surrounds the cell. The cell wall contains not only cellulose and protein, but other polysaccharides as well. In fact, two other classes of polysaccharides, hemicelluloses and pectic polysaccharides, can comprise 30% of the dry mass of the cell wall. The cell wall provides structural support and protection. Pores in the cell wall allow water and nutrients to move into and out of the cell. The cell wall also prevents the plant cell from bursting when water enters the cell. |
Surface tension of alveolar fluid, which is mostly water, creates an inward pull of the tissue of what organ? | heart | spleen | brain | lung | Intrapleural pressure is the pressure of the air within the pleural cavity, between the visceral and parietal pleurae. Similar to intra-alveolar pressure, intrapleural pressure also changes during the different phases of breathing. However, due to certain characteristics of the lungs, the intrapleural pressure is always lower than, or negative to, the intra-alveolar pressure (and therefore also to atmospheric pressure). Although it fluctuates during inspiration and expiration, intrapleural pressure remains approximately –4 mm Hg throughout the breathing cycle. Competing forces within the thorax cause the formation of the negative intrapleural pressure. One of these forces relates to the elasticity of the lungs themselves—elastic tissue pulls the lungs inward, away from the thoracic wall. Surface tension of alveolar fluid, which is mostly water, also creates an inward pull of the lung tissue. This inward tension from the lungs is countered by opposing forces from the pleural fluid and thoracic wall. Surface tension within the pleural cavity pulls the lungs outward. Too much or too little pleural fluid would hinder the creation of the negative intrapleural pressure; therefore, the level must be closely monitored by the mesothelial cells and drained by the lymphatic system. Since the parietal pleura is attached to the thoracic wall, the natural elasticity of the chest wall opposes the inward pull of the lungs. Ultimately, the outward pull is slightly greater than the inward pull, creating the –4 mm Hg intrapleural pressure relative to the intraalveolar pressure. Transpulmonary pressure is the difference between the intrapleural and intra-alveolar pressures, and it determines the size of the lungs. A higher transpulmonary pressure corresponds to a larger lung. |
What type of tumor mostly does not cause serious problems and can be completely removed by surgery? | malignant | toxic | persistent | benign | |
What supports and protects the soft organs of the body? | Muscle | Skin | skull | skeleton | Protection. The skeleton supports and protects the soft organs of the body. For example, the skull surrounds the brain to protect it from injury. The bones of the rib cage help protect the heart and lungs. |
What celestial body is the earth’s main source of energy? | moon | rivers | ocean | sun | The Sun is Earth’s main source of energy. The Sun gives us both light and heat. The Sun changes hydrogen into helium through nuclear fusion. This releases huge amounts of energy. The energy travels to Earth mostly as visible light. The energy is carried through the empty space by radiation . We can use sunlight as an energy resource, called solar energy. |
What do you call the horizontal stems of a strawberry plant that run over the ground surface? | sprouts | root volunteers | climbing vines | stolons | Strawberry plants have horizontal stems called stolons that run over the ground surface. If they take root, they form new plants. |
Glaciers are incredibly powerful agents of what? | extinction | climate change | insulation | erosion | Glaciers are incredibly powerful agents of erosion. |
What type of pressure is the pressure exerted by gas particles in earth’s atmosphere as those particles collide with objects? | adjacent pressure | vertical pressure | adjacent pressure | atmospheric pressure | Atmospheric pressure is the pressure exerted by gas particles in Earth’s atmosphere as those particles collide with objects. A barometer is an instrument used to measure atmospheric pressure. A traditional mercury barometer consists of an evacuated tube immersed in a container of mercury. Air molecules push down on the surface of the mercury. Because the inside of the tube is a vacuum, the mercury rises inside the tube. The height to which the mercury rises is dependent on the external air pressure. |
What helps the plasma membrane keep its shape? | cytoplasm | molecules of carbohydrates | molecules of oxygen | molecules of cholesterol | The plasma membrane also contains other molecules, primarily other lipids and proteins. The green molecules in Figure above , for example, are the lipid cholesterol. Molecules of cholesterol help the plasma membrane keep its shape. Many of the proteins in the plasma membrane assist other substances in crossing the membrane. |
What type of reproduction only involves one parent? | binary | primitive | organic | asexual | Asexual reproduction involves just one parent. It produces offspring that are genetically identical to the parent. Methods of asexual reproduction include binary fission, fragmentation, and budding. |
What is defined as a repeating series of events that include growth, dna synthesis, and cell division? | puberty | photosynthesis | meiosis | cell cycle | Cell division is just one of several stages that a cell goes through during its lifetime. The cell cycle is a repeating series of events that include growth, DNA synthesis, and cell division. The cell cycle in prokaryotes is quite simple: the cell grows, its DNA replicates, and the cell divides. In eukaryotes, the cell cycle is more complicated. |
How metalloids behave in chemical interactions with other elements depends mainly on the number of what, in the outer energy level of their atoms? | neutrons | protons | positrons | electrons | How metalloids behave in chemical interactions with other elements depends mainly on the number of electrons in the outer energy level of their atoms. Metalloids have from three to six electrons in their outer energy level. Boron, pictured in the Figure below , is the only metalloid with just three electrons in its outer energy level. It tends to act like metals by giving up its electrons in chemical reactions. Metalloids with more than four electrons in their outer energy level (arsenic, antimony, and tellurium) tend to act like nonmetals by gaining electrons in chemical reactions. Those with exactly four electrons in their outer energy level (silicon and germanium) may act like either metals or nonmetals, depending on the other elements in the reaction. |
What distinguishing characteristic of annelid anatomy shows specialization and adaptation? | compression | asymmetry | beautiful | segmentation | Annelids are divided into many repeating segments. The earthworm in Figure below is an annelid. You can clearly see its many segments. Segmentation of annelids is highly adaptive. Each segment has its own nerve and muscle tissues. This allows the animal to move very efficiently. Some segments can also be specialized to carry out particular functions. They may have special structures on them. For example, they might have tentacles for sensing or feeding, “paddles” for swimming, or suckers for clinging to surfaces. |
The spermatids are transported from the testes to where? | vas | abdominis | Duodenum | epididymis | The spermatids are transported from the testes to the epididymis. Involuntary muscular contraction moves the spermatids along. |
How does water from roots reach the leaves? | water-phobic cells | water - combining cells | water - raising cells | water-conducting cells | |
As a polycrystalline material solidifies, grains with irregular shapes form. the interfaces between grains constitute grain what? | obstacles | waves | patterns | boundaries | Grain boundaries. As a polycrystalline material solidifies, grains with irregular shapes form. The interfaces between grains constitute grain boundaries. (Squares represent unit cells within grains. |
Motors are the most common application of magnetic force on current-carrying wires. motors have loops of wire in this? | spark plugs | electrical circuit | capacitors | magnetic field | 22.8 Torque on a Current Loop: Motors and Meters Motors are the most common application of magnetic force on current-carrying wires. Motors have loops of wire in a magnetic field. When current is passed through the loops, the magnetic field exerts torque on the loops, which rotates a shaft. Electrical energy is converted to mechanical work in the process. (See Figure 22.34. |
What makes and stores pigments that give petals and fruit their orange and yellow colors? | pores | sporozoans | protozoa | chromoplasts | Chromoplasts make and store pigments that give petals and fruit their orange and yellow colors. |
What term is used to describe when a liquid is the temperature at which its equilibrium vapor pressure is equal to the pressure exerted on the liquid by its gaseous surroundings? | evaporating point | freezing point | burning point | boiling point | Boiling Points When the vapor pressure increases enough to equal the external atmospheric pressure, the liquid reaches its boiling point. The boiling point of a liquid is the temperature at which its equilibrium vapor pressure is equal to the pressure exerted on the liquid by its gaseous surroundings. For liquids in open containers, this pressure is that due to the earth’s atmosphere. The normal boiling point of a liquid is defined as its boiling point when surrounding pressure is equal to 1 atm (101.3 kPa). Figure 10.24 shows the variation in vapor pressure with temperature for several different. |
When electrons return to a lower energy level, they emit the excess energy in the form of what? | energy | weight | electricity | light | When electrons return to a lower energy level, they emit energy in the form of light. |
What is another term for nearsightedness? | anemia | hypoxia | glaucoma | myopia | Nearsightedness, or myopia, is the condition in which nearby objects are seen clearly, but distant objects are blurry. It occurs when the eyeball is longer than normal. This causes images to be focused in front of the retina. Myopia can be corrected with concave lenses. The lenses focus images farther back in the eye, so they are on the retina instead of in front of it. |
What are the areas located at fixed distances from the nucleus of the atom? | orbit points | molar levels | atomic regions | energy levels | Basic to Bohr’s model is the idea of energy levels. Energy levels are areas located at fixed distances from the nucleus of the atom. They are the only places where electrons can be found. Energy levels are a little like rungs on a ladder. You can stand on one rung or another but not between the rungs. The same goes for electrons. They can occupy one energy level or another but not the space between energy levels. |
In which state of matter do particles take the shape of their container, but cannot expand to fill it? | chemical | gas | mixture | liquid | A liquid is a state of matter in which particles can slip past one another and take the shape of their container. However, the particles cannot pull apart and spread out to take the volume of their container. |
Runoff is likely to cause more what if the land is bare? | weathering | abrasion | sediment | erosion | Runoff is likely to cause more erosion if the land is bare. Plants help hold the soil in place. The runoff water in Figure below is brown because it eroded soil from a bare, sloping field. Can you find evidence of erosion by runoff where you live? What should you look for?. |
Cations have what type of charge? | constant | negative | neutral | positive | Cations have positive charges, and anions have negative charges. |
What organ is subdivided into ascending, descending, transverse and sigmoid parts? | lungs | heart | uterus | colon | Colon The cecum blends seamlessly with the colon. Upon entering the colon, the food residue first travels up the ascending colon on the right side of the abdomen. At the inferior surface of the liver, the colon bends to form the right colic flexure (hepatic flexure) and becomes the transverse colon. The region defined as hindgut begins with the last third of the transverse colon and continues on. Food residue passing through the transverse colon travels across to the left side of the abdomen, where the colon angles sharply immediately inferior to the spleen, at the left colic flexure (splenic flexure). From there, food residue passes through the descending colon, which runs down the left side of the posterior abdominal wall. After entering the pelvis inferiorly, it becomes the s-shaped sigmoid colon, which extends medially to the midline (Figure 23.21). The ascending and descending colon, and the rectum (discussed next) are located in the retroperitoneum. The transverse and sigmoid colon are tethered to the posterior abdominal wall by the mesocolon. |
Ammonia, urea, and uric acid are examples of what kind of waste? | oxygenous | carbonous | sulphurous | nitrogenous | |
What are variants of genes called? | allergens | antigens | mutations | alleles | Recall that our DNA is wound into chromosomes . Each of our chromosomes contains a long chain of DNA that encodes hundreds, if not thousands, of genes. Each of these genes can have slightly different versions from individual to individual. These variants of genes are called alleles . Each parent only donates one allele for each gene to an offspring. |
Mushrooms are an example of what type of organism, which includes beneficial and toxic specimens? | seeds | spores | bacteria | fungi | Some of the best known types of fungi are mushrooms, which can be edible or poisonous ( Figure below ). Many species are grown commercially, but others are harvested from the wild. When you order a pizza with mushrooms or add them to your salad, you are most likely eating Agaricus bisporus , known as white or button mushrooms, the most commonly eaten species. Other mushroom species are gathered from the wild for people to eat or for commercial sale. Many mushroom species are poisonous to humans. Some mushrooms will simply give you a stomachache, while others may kill you. Some mushrooms you can eat when they are cooked but are poisonous when raw. So if you find mushrooms in the wild, don't eat them until you are certain they are safe!. |
Comparing what sequences provides clues to evolution and development? | organisms | DNA | genes | genome | 21.6 Comparing genome sequences provides clues to evolution and development. |
What is a measure of the average amount of energy of motion, or kinetic energy, a system contains called? | precipitation | size | variation | temperature | There are other units in chemistry that are important, and we will cover others in the course of the entire book. One of the fundamental quantities in science is temperature. Temperature is a measure of the average amount of energy of motion, or kinetic energy, a system contains. Temperatures are expressed using scales that use units called degrees, and there are several temperature scales in use. In the United States, the commonly used temperature scale is the Fahrenheit scale (symbolized by °F and spoken as “degrees Fahrenheit”). On this scale, the freezing point of liquid water (the temperature at which liquid water turns to solid ice) is 32°F, and the boiling point of water (the temperature at which liquid water turns to steam) is 212°F. Science also uses other scales to express temperature. The Celsius scale (symbolized by °C and spoken as “degrees Celsius”) is a temperature scale where 0°C is the freezing point of water and 100°C is the boiling point of water; the scale is divided into 100 divisions between these two landmarks and extended higher and lower. By comparing the Fahrenheit and Celsius scales, a conversion between the two scales can be determined: °C=(°F–32) × 59° Saylor URL: http://www. saylor. org/books. |
What is the minimum mass capable of supporting sustained fission called? | particular mass | concentrated mass | baseline mass | critical mass | U92235 + n01® B56141a + K3692r + 3n01 This hypothesis was confirmed by detecting the krypton-92 fission product. As discussed in Section 20.2 "Nuclear Reactions", the nucleus usually divides asymmetrically rather than into two equal parts, and the fission of a given nuclide does not give the same products every time. In a typical nuclear fission reaction, more than one neutron is released by each dividing nucleus. When these neutrons collide with and induce fission in other neighboring nuclei, a self-sustaining series of nuclear fission reactions known as anuclear chain reaction can result (Figure 20.16 "The Curve of Nuclear Binding Energy"). For example, the fission of 235U releases two to three neutrons per fission event. If absorbed by other 235U nuclei, those neutrons induce additional fission events, and the rate of the fission reaction increases geometrically. Each series of events is called a generation. Experimentally, it is found that some minimum mass of a fissile isotope is required to sustain a nuclear chain reaction; if the mass is too low, too many neutrons are able to escape without being captured and inducing a fission reaction. The minimum mass capable of supporting sustained fission is called the critical mass. This amount depends on the purity of the material and the shape of the mass, which corresponds to the amount of surface area available from which neutrons can escape, and on the identity of the isotope. If the mass of the fissile isotope is greater than the critical mass, then under the right conditions, the resulting supercritical mass can release energy explosively. The enormous energy released from nuclear chain reactions is responsible for the massive destruction caused by the detonation of nuclear weapons such as fission bombs, but it also forms the basis of the nuclear power industry. Nuclear fusion, in which two light nuclei combine to produce a heavier, more stable nucleus, is the opposite of nuclear fission. As in the nuclear transmutation reactions discussed in Section 20.2 "Nuclear. |
Many hydrocarbons are cyclic and adopt specific three-dimensional structures that influence their physical and what properties? | radiation | liquid | electrical | chemical | Many hydrocarbons are cyclic and adopt specific three-dimensional structures that influence their physical and chemical properties. |
The secondary wall contains _________ , a secondary cell component in plant cells that have completed cell growth/expansion. | cellulose | cytoplasm | glucogen | lignin | Microtubules guide the formation of the plant cell wall. Cellulose is laid down by enzymes to form the primary cell wall. Some plants also have a secondary cell wall. The secondary wall contains a lignin, a secondary cell component in plant cells that have completed cell growth/expansion. |
What does the cell cycle do? | only reproduce cells | only divide cells | create new cells | divide and reproduce cells | The cell cycle is a repeating series of events, characterizing the life of a eukaryotic cell. |
Inside the nasal area of the skull, the nasal cavity is divided into halves by the what? | cell wall | cerebral cortex | cytoplasm | nasal septum | Inside the nasal area of the skull, the nasal cavity is divided into halves by the nasal septum. The upper portion of the nasal septum is formed by the perpendicular plate of the ethmoid bone and the lower portion is the vomer bone. Each side of the nasal cavity is triangular in shape, with a broad inferior space that narrows superiorly. When looking into the nasal cavity from the front of the skull, two bony plates are seen projecting from each lateral wall. The larger of these is the inferior nasal concha, an independent bone of the skull. Located just above the inferior concha is the middle nasal concha, which is part of the ethmoid bone. A third bony plate, also part of the ethmoid bone, is the superior nasal concha. It is much smaller and out of sight, above the middle concha. The superior nasal concha is located just lateral to the perpendicular plate, in the upper nasal cavity. |
Bacteria can be chemotrophs, which obtain what by breaking down chemical compounds in their environment? | food | waste | chemials | energy | Bacteria can also be chemotrophs. Chemosynthetic bacteria, or chemotrophs , obtain energy by breaking down chemical compounds in their environment. An example of one of these chemicals broken down by bacteria is nitrogen-containing ammonia. These bacteria are important because they help cycle nitrogen through the environment for other living things to use. Nitrogen cannot be made by living organisms, so it must be continually recycled. Organisms need nitrogen to make organic compounds, such as DNA. |
Habitat loss, introduced species, overharvesting, and global change are major threats to what? | transportation | the earth's gravity | the sun | biodiversity | |
What "plumbing" structures inside the veins maintain a unidirectional flow of blood despite the low blood pressure? | pumps | funnels | tubes | valves | |
What do we call the cartilaginous structure that surrounds the notochrod? | membrane | osteocytes | clavicle | arcualia | distinctly differ from the adult form, spending 3 to 15 years as suspension feeders. Once they attain sexual maturity, the adults reproduce and die within days. Lampreys possess a notochord as adults; however, this notochord is surrounded by a cartilaginous structure called an arcualia, which may resemble an evolutionarily early form of the vertebral column. |
What is the process of the transfer of pollen from an anther to a stigma in angiosperms called? | wind | grabation | evolution | pollination | |
Despite its small size, an erythrocyte contains about 250 million molecules of what? | potassium | calcium | plasma | hemoglobin | |
How many variables are used to describe the condition of a gas? | three | five | one | four | Recall from the kinetic-molecular theory that gas particles move randomly and in straight lines until they elastically collide with either other gas particles or with one of the walls of the container. It is these collisions with the walls of the container that defines the pressure of the gas. Four variables are used to describe the condition of a gas. They are pressure , volume , temperature , and the amount of the gas as measured by the number moles . We will examine separately how the volume, temperature, and amount of gas each affect the pressure of an enclosed gas sample. |
What is a suggested explanation for a phenomenon or a suggested explanation for a relationship between many phenomena called? | process | query | system | hypothesis | In order to explain the observed phenomenon, scientists develop a number of possible explanations, or hypotheses. A hypothesis is a suggested explanation for a phenomenon or a suggested explanation for a relationship between many phenomena. Hypotheses are always based on evidence that can be tested by observation or experimentation. Scientific investigations are required to test hypotheses. Scientists mostly base hypotheses on prior observations or on extensions of existing scientific explanations. |
Land plants are classified into two major groups according to the absence or presence of what tissue? | bacterial | disease | root | vascular | The Major Divisions of Land Plants Land plants are classified into two major groups according to the absence or presence of vascular tissue, as detailed in Figure 14.8. Plants that lack vascular tissue formed of specialized cells for the transport of water and nutrients are referred to as nonvascular plants. The bryophytes, liverworts, mosses, and hornworts are seedless and nonvascular, and likely appeared early in land plant evolution. Vascular plants developed a network of cells that conduct water and solutes through the plant body. The first vascular plants appeared in the late Ordovician (461–444 million years ago) and were probably similar to lycophytes, which include club mosses (not to be confused with the mosses) and the pterophytes (ferns, horsetails, and whisk ferns). Lycophytes and pterophytes are referred to as seedless vascular plants. They do not produce seeds, which are embryos with their stored food reserves protected by a hard casing. The seed plants form the largest group of all existing plants and, hence, dominate the landscape. Seed plants include gymnosperms, most notably conifers, which produce “naked. |
What type of treatment is necessary for anaphylaxis? | intensive care | outpatient | allergy shot | emergency | In some people, a food allergy can trigger a severe allergic reaction called anaphylaxis. Emergency treatment is critical for anaphylaxis. Untreated, anaphylaxis can cause a coma or death. Anaphylaxis is vary rare. The vast majority of people will never have an anaphylactic reaction. The life-threatening symptoms of anaphylaxis include:. |