Food chewed evenly during mastication moisten and lubricate the lining of the mouth and this?
Food is chewed evenly during mastication Moisten and lubricate the lining of the mouth and pharynx.
Photosynthesis is initiated by what hitting plants?
Every split second that sunlight hits that leaf, photosynthesis is initiated, bringing energy into the ecosystem. It could be said that this is one of the most important - if not the absolutely most important - biochemical reactions. And it all starts with the leaf.
What is the process of drawing general conclusions based on many pieces of evidence?
experimental reasoning
quantum reasoning
primitive reasoning
inductive reasoning
Inductive reasoning is the process of drawing general conclusions based on many pieces of evidence. This type of reasoning is the basis of the scientific method.
Name the fibrous joint in which two parallel bones are united to each other by fibrous connective tissue.
Syndesmosis A syndesmosis (“fastened with a band”) is a type of fibrous joint in which two parallel bones are united to each other by fibrous connective tissue. The gap between the bones may be narrow, with the bones joined by ligaments, or the gap may be wide and filled in by a broad sheet of connective tissue called an interosseous membrane. In the forearm, the wide gap between the shaft portions of the radius and ulna bones are strongly united by an interosseous membrane (see Figure 9.5b). Similarly, in the leg, the shafts of the tibia and fibula are also united by an interosseous membrane. In addition, at the distal tibiofibular joint, the articulating surfaces of the bones lack cartilage and the narrow gap between the bones is anchored by fibrous connective tissue and ligaments on both the anterior and posterior aspects of the joint. Together, the interosseous membrane and these ligaments form the tibiofibular syndesmosis. The syndesmoses found in the forearm and leg serve to unite parallel bones and prevent their separation. However, a syndesmosis does not prevent all movement between the bones, and thus this type of fibrous joint is functionally classified as an amphiarthrosis. In the leg, the syndesmosis between the tibia and fibula strongly unites the bones, allows for little movement, and firmly locks the talus bone in place between the tibia and fibula at the ankle joint. This provides strength and stability to the leg and ankle, which are important during weight bearing. In the forearm, the interosseous membrane is flexible enough to allow for rotation of the radius bone during forearm movements. Thus in contrast to the stability provided by the tibiofibular syndesmosis, the flexibility of the antebrachial interosseous membrane allows for the much greater mobility of the forearm. The interosseous membranes of the leg and forearm also provide areas for muscle attachment. Damage to a syndesmotic joint, which usually results from a fracture of the bone with an accompanying tear of the interosseous membrane, will produce pain, loss of stability of the bones, and may damage the muscles attached to the interosseous membrane. If the fracture site is not properly immobilized with a cast or splint, contractile activity by these muscles can cause improper alignment of the broken bones during healing.
What's the best way humans can conserve water?
salt it
boil it
use more
use less
The water supply can be harmed in two major ways. The water can be polluted, and it can be overused. Protecting the water supply must address both problems. We need to reduce how much pollution ends up in the water supply—keeping water from being polluted is easier and cheaper than cleaning it. We need to treat water that’s already polluted. We need to conserve water by using less.
Although fewer in number than chemical synapses, what type of synapses are found in all nervous systems and play important and unique roles?
dual synapses
duplicating synapses
beginning synapses
electrical synapses
Electrical Synapse While electrical synapses are fewer in number than chemical synapses, they are found in all nervous systems and play important and unique roles. The mode of neurotransmission in electrical synapses is quite different from that in chemical synapses. In an electrical synapse, the presynaptic and postsynaptic membranes are very close together and are actually physically connected by channel proteins forming gap junctions. Gap junctions allow current to pass directly from one cell to the next. In addition to the ions that carry this current, other molecules, such as ATP, can diffuse through the large gap junction pores. There are key differences between chemical and electrical synapses. Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is unidirectional. Signaling in electrical synapses, in contrast, is virtually instantaneous (which is important for synapses involved in key reflexes), and some electrical synapses are bidirectional. Electrical synapses are also more reliable as they are less likely to be blocked, and they are important for synchronizing the electrical activity of a group of neurons. For example, electrical synapses in the thalamus are thought to regulate slow-wave sleep, and disruption of these synapses can cause seizures.
What consists of a nitrogen atom bonded to some combination of carbons and hydrogens?
a chloride
an alkali
a metalloid
an amine
An amine consists of a nitrogen atom bonded to some combination of carbons and hydrogens.
When do hammerhead sharks usually hunt?
in the day
at night
Figure 29.11 Hammerhead sharks tend to school during the day and hunt prey at night. (credit: Masashi Sugawara).
What types of glands do only female mammals have?
Two traits are used to define the mammal class. They are fur or hair and mammary glands in females.
What is the unit used to measure air pressure?
pounds per inch
The weather map pictured below ( Figure above ) shows air pressure. The lines on the map connect places that have the same air pressure. Air pressure is measured in a unit called the millibar. Isobars are the lines that connect the points with the same air pressure. The map also shows low- and high-pressure centers and fronts. Find the cold front on the map. This cold front is likely to move toward the northeast over the next couple of days. How could you use this information to predict what the weather will be on the East Coast?.
In which stage does the chromatin condense into chromosomes?
Anaphase I
Metaphase I
Telophase II
prophase ii
In prophase II, once again the nucleolus disappears and the nucleus breaks down. The chromatin condenses into chromosomes. The spindle begins to reform as the centrioles move to opposite sides of the cell.
What is the upper-most atmosphere known as?
The atmosphere is a big part of the water cycle. What do you think would happen to Earth’s water without it?.
Reproduction that doesn't involve a male gamete is also known as what?
asexual reproduction
Agamogenesis is any form of reproduction that does not involve a male gamete. These include are parthenogenesis and apomixis. Parthenogenesis is a form of asexual reproduction where growth and development of embryos occur without fertilization. Parthenogenesis occurs naturally in aphids, rotifers, nematodes and some other invertebrates, as well as in many plants and certain lizards, such as the Komodo dragon. Apomixis is asexual reproduction, without fertilization, in plants.
What is the term for an electronic component that consists of many other electronic components?
electrical current
creating circuit
integrated circuit
An integrated circuit (microchip) is an electronic component that consists of many other electronic components such as transistors. Integrated circuits are used in virtually all modern electronic devices to carry out specific tasks.
What is another term for life science?
Life science is the study of life and living organisms. Life science is also called biology.
What type of cartilage contains no collagen?
joint cartilage
fetal cartilage
shark cartilage
lamprey cartilage
In prokaryotes, what are the regions called that repressors bind to?
For a bacteria, many aspects of gene regulation are due to the presence or absence of certain nutrients. In prokaryotes, repressors bind to regions called operators that are generally located immediately downstream from the promoter. Activators bind to the upstream portion of the promoter.
What instrument has a resolution many times greater than a light microscope, and can be used to see the details on the outside of a cell?
molecular microscope
complex microscope
element microscope
electron microscope
Use an electron microscope. This instrument has a resolution many times greater than a light microscope, and can be used to see the details on the outside of a cell. Some electron microscopes can also be used to see the details inside a cell.
The temperature at which the individual ions have enough kinetic energy to overcome the attractive forces that hold them in place is called?
last point
occurring point
boiling point
melting point
The Relationship between Lattice Energies and Physical Properties The magnitude of the forces that hold an ionic substance together has a dramatic effect on many of its properties. The melting point, for example, is the temperature at which the individual ions have enough kinetic energy to overcome the attractive forces that hold them in place. At the melting point, the ions can move freely, and the substance becomes a liquid. Thus melting points vary with lattice energies for ionic substances that have similar structures. The melting points of the sodium halides (Figure 8.3 "A Plot of Melting Point versus the Identity of the Halide for the Sodium Halides"), for example, decrease smoothly from NaF to NaI, following the same trend as seen for their lattice energies (Figure 8.2 "A Plot of Lattice Energy versus the Identity of the Halide for the Lithium, Sodium, and Potassium Halides"). Similarly, the melting point of MgO is 2825°C, compared with 996°C for NaF, reflecting the higher lattice energies associated with higher charges on the ions. In fact, because of its high melting point, MgO is used as an electrical insulator in heating elements for electric stoves. Figure 8.3 A Plot of Melting Point versus the Identity of the Halide for the Sodium Halides.
What play several important roles in the human body?
Lipids play several important roles in the body. Triglycerides are stored in fat cells until the body needs to break them down for chemical energy. These stored triglycerides also help insulate the body against extreme temperatures and cushion organs against physical jostling. Phospholipids and cholesterol are important constituents of the cell membrane. These compounds provide structural integrity to the cell wall, since they are not water-soluble. Other steroids are used as chemical messengers in the body, and the fat-soluble vitamins serve a variety of other functions.
What is a measure that has both size and direction?
Force is a vector, or a measure that has both size and direction. For example, Colton pushes on the ground in the opposite direction that the scooter moves, so that’s the direction of the force he is applies. He can give the scooter a strong push or a weak push. That’s the size of the force. Like other vectors, a force can be represented with an arrow. You can see some examples in the Figure below . The length of each arrow represents the strength of the force, and the way the arrow points represents the direction of the force.
What is to blame for water’s boiling point (100°c) being higher than the boiling points of similar substances?
helium bonds
electrode bonds
molecular shape
hydrogen bonds
Hydrogen bonds also explain why water’s boiling point (100°C) is higher than the boiling points of similar substances without hydrogen bonds. Because of water’s relatively high boiling point, most water exists in a liquid state on Earth. Liquid water is needed by all living organisms. Therefore, the availability of liquid water enables life to survive over much of the planet.
Carbonic acid decomposes easily at room temperature into carbon dioxide and what else?
Some unstable acids decompose to produce nonmetal oxides and water. Carbonic acid decomposes easily at room temperature into carbon dioxide and water.
What form when a single atom gains or loses electrons?
carbon atoms
fusional ions
vacuoles ions
monatomic ions
Monatomic ions form when a single atom gains or loses electrons. For the main group elements, cations are generally formed by removing all of the valence electrons from the atom. Since the numbers of valence electrons for the representative elements are constant within a particular group, all we need is the group number of a given element to know its charge when it becomes a cation. Group 1 elements form ions with a 1+ charge, Group 2 metal ions have a 2+ charge, and the ions of Group 13 elements tend to have a 3+ charge. Heavier p-block metals such as tin and lead are special cases and will be discussed with the transition metal ions. The name of a monatomic cation is the same as the name of the neutral element. For example, the sodium atom (Na) loses a single electron to form the sodium ion (Na + ), while Al 3+ is an aluminum ion.
In earthworms, the skin serves as what type of organ?
Catalytic converters used on motor vehicles break down pollutants in what, yielding non-toxic compounds?
Catalytic converters are used on motor vehicles. They break down pollutants in exhaust to non-toxic compounds. For example, they change nitrogen oxides to harmless nitrogen and oxygen gases.
Processing of filtrate in the proximal tubule helps maintain what level in body fluid?
metabolic level
What helps represent age-sex structure of the population?
biome model
habitat chart
density graph
population pyramid
The age-sex structure of a population is the number of individuals of each sex and age in the population. Age-sex structure influences population growth. It is represented by a population pyramid. The number of survivors at each age is plotted on a survivorship curve.
Large viruses began as what type of cells inside bigger host cells?
Large viruses were once parasitic cells inside bigger host cells. Over time, genes needed to survive and reproduce outside host cells were lost.
How can you calculate the density of matter?
by dividing its volume by its mass
by subtracting mass from volume
by multiplying its mass by its volume
by dividing its mass by its volume
The density of matter can be calculated by dividing its mass by its volume.
Frogs and toads have long back legs which are specialized for what action?
Frogs The frog order also includes toads. Unlike other amphibians, frogs and toads lack a tail by adulthood. Their back legs are also longer because they are specialized for jumping. Frogs can jump as far as 20 times their body length. That’s like you jumping more than the length of a basketball court! red-eyed tree frog.
Different regions of the cerebral cortex can be associated with particular functions, a concept known as what?
cytoplasm of function
reversal of function
expressiveness of function
localization of function
Different regions of the cerebral cortex can be associated with particular functions, a concept known as localization of function. In the early 1900s, a German neuroscientist named Korbinian Brodmann performed an extensive study of the microscopic anatomy—the cytoarchitecture—of the cerebral cortex and divided the cortex into 52 separate regions on the basis of the histology of the cortex. His work resulted in a system of classification known as Brodmann’s areas, which is still used today to describe the anatomical distinctions within the cortex (Figure 13.8). The results from Brodmann’s work on the anatomy align very well with the functional differences within the cortex. Areas 17 and 18 in the occipital lobe are responsible for primary visual perception. That visual information is complex, so it is processed in the temporal and parietal lobes as well. The temporal lobe is associated with primary auditory sensation, known as Brodmann’s areas 41 and 42 in the superior temporal lobe. Because regions of the temporal lobe are part of the limbic system, memory is an important function associated with that lobe. Memory is essentially a sensory function; memories are recalled sensations such as the smell of Mom’s baking or the sound of a barking dog. Even memories of movement are really the memory of sensory feedback from those movements, such as stretching muscles or the movement of the skin around a joint. Structures in the temporal lobe.
What is the term for a change in the inherited traits of organisms over time?
Darwin proposed the theory of evolution by natural selection. Evolution is a change in the inherited traits of organisms over time. Natural selection is the process by which living things with beneficial traits produce more offspring, so their traits become more common over time.
What type of diseases do antibiotics not affect?
animal stings
autoimmune diseases
Viruses are not affected by antibiotics. Several viral diseases can be treated with antiviral drugs or prevented with vaccines.
Which system carries out long-distance transport of materials between the root and shoot systems?
perceptual tissue system
circulatory tissue system
reproductive tissue system
vascular tissue system
How do reptiles typically reproduce?
live birth
Reptiles typically reproduce sexually and lay eggs.
All organisms must adapt to what in order to survive?
All organisms must adapt to their environment in order to survive. This is true whether they live in water or on land. Most environments are not as extreme as the deep ocean where tube worms live. But they all have conditions that require adaptations. In this chapter, you will read about a wide variety of environments and the organisms that live in them.
Biochemical compounds that include sugars, starches, and cellulose are examples of what?
Carbohydrates are biochemical compounds that include sugars, starches, and cellulose. They contain carbon, hydrogen, and oxygen, and they are used mainly for energy by living things.
What emerges from an insect egg?
When an insect egg hatches, a larva emerges. The larva eats and grows and then enters the pupa stage. The pupa is immobile and may be encased in a cocoon . During the pupa stage, the insect goes through metamorphosis . Tissues and appendages of the larva break down and reorganize into the adult form. How did such an incredible transformation evolve? Metamorphosis is actually very advantageous. It allows functions to be divided between life stages. Each stage can evolve adaptations to suit it for its specific functions without affecting the adaptations of the other stage.
What can protons and neutrons be broken down into?
Today, scientists think that electrons truly are fundamental particles that cannot be broken down into smaller, simpler particles. They are a type of fundamental particles called leptons. Protons and neutrons, on the other hand, are no longer thought to be fundamental particles. Instead, they are now thought to consist of smaller, simpler particles of matter called quarks. Scientists theorize that leptons and quarks are held together by yet another type of fundamental particles called bosons. All three types of fundamental particles—leptons, quarks, and bosons—are described below. The following Figure below shows the variety of particles of each type.
What is the name of the stage of life when a child becomes sexually mature?
growth spurt
Puberty is the stage of life when a child becomes sexually mature. Puberty lasts from about 10 to 16 years of age in girls and from about 12 to 18 years of age in boys. In both girls and boys, puberty begins when the pituitary gland signals the gonads (ovaries or testes) to start secreting sex hormones (estrogen in girls, testosterone in boys). Sex hormones, in turn, cause many other changes to take place.
What part of the brain is divided from front to back into the left and right hemispheres?
medula oblongata
The cerebrum is divided down the middle from the front to the back of the head. The two halves of the cerebrum are called the right and left hemispheres. The two hemispheres are very similar but not identical. They are connected to each other by a thick bundle of axons deep within the brain. These axons allow the two hemispheres to communicate with each other. Did you know that the right hemisphere of the cerebrum controls the left side of the body, and vice versa? This can happen because of the connections between the two hemispheres.
Because their cells are arranged in bundles, the appearance of skeletal and cardiac muscles is described as what?
http://zonalandeducation. com/mstm/physics/mechanics/vectors/introduction/introductionVectors. html.
What resource is considered nonrewable for human purposes, because it takes so long to form and is depleted by farming and other activities?
Although renewable, soil takes a very long to form—up to hundreds of millions of years. So, for human purposes, soil is a nonrenewable resource. It is also constantly depleted of nutrients through careless use and eroded by wind and water. For example, misuse of soil caused a huge amount of it to simply blow away in the 1930s during the Dust Bowl (see Figure below ). Soil must be used wisely to preserve it for the future. Conservation practices include contour plowing and terracing. Both reduce soil erosion. Soil also must be protected from toxic wastes.
What in orange juice makes it taste sour?
amino acid
acetic acid
citric acid
Some solutions have special properties because they are acids. Orange juice is an example. It contains an acid called citric acid. It makes orange juice taste sour. Some solutions are bases rather than acids.
What scientist created the modern system for classifying organisms?
Linnaeus published his classification system in the 1700s. Since then, many new species have been discovered. The biochemistry of many organisms has also become known. Eventually, scientists realized that Linnaeus’s system of classification needed revision.
What will be the effect to an organism if its homeostasis is not maintained?
healthy mental state
slow aging
weight regulation
death or disease
All of the organ systems of the body work together to maintain homeostasis of the organism. If homeostasis fails, death or disease may result.
Since warmer molecules have more energy, they are more what?
The density of air varies from place to place. Air density depends on several factors. One is temperature. Like other materials, warm air is less dense than cool air. Since warmer molecules have more energy, they are more active. The molecules bounce off each other and spread apart. Another factor that affects the density of air is altitude.
If only blue light strikes green leaves what happens to it?
it causes cooling
it causes heating
it is reflected
it is absorbed
The color of light that strikes an object may also affect the color that the object appears. For example, if only blue light strikes green leaves, the blue light is absorbed and no light is reflected.
Which type of animal creates useful substances such as honey, wax, lacquer, and silk?
Insects produce useful substances, such as honey, wax, lacquer, and silk.
Stringed instruments can help show the relationship between tension and what in strings?
f 2 = v w / λ 2 = v w / 2L = 2 f 1 . Similarly, f 3 = 3 f 1 , and so on. All of these frequencies can be changed by adjusting the tension in the string. The greater the tension, the greater v w is and the higher the frequencies. This observation is familiar to anyone who has ever observed a string instrument being tuned. We will see in later chapters that standing waves are crucial to many resonance phenomena, such as in sounding boxes on string instruments.
Ectotherms undergo a variety of changes at the cellular level to acclimatize to shifts in what?
There are 44 autosomes and 2 sex chromosomes in the human genome, for a total of 46 chromosomes (23 pairs). Sex chromosomes specify an organism's genetic sex. Humans can have two different sex chromosomes, one called X and the other Y. Normal females possess two X chromosomes and normal males one X and one Y. An autosome is any chromosome other than a sex chromosome. The Figure below shows a representation of the 24 different human chromosomes. Figure below shows a karyotype of the human genome. A karyotype depicts, usually in a photograph, the chromosomal complement of an individual, including the number of chromosomes and any large chromosomal abnormalities. Karyotypes use chromosomes from the metaphase stage of mitosis.
Convex lenses are thicker in the middle than at the edges so they cause rays of light to converge, or meet, at a point called what?
the apex
the center
the base
Convex lenses are thicker in the middle than at the edges. They cause rays of light to converge, or meet, at a point called the focus (F). Convex lenses form either real or virtual images. It depends on how close an object is to the lens relative to the focus. Figure below shows how a convex lens works. You can also interact with an animated convex lens at the URL below. An example of a convex lens is a hand lens.
What are magnesium carbonate, aluminum hydroxide, and sodium bicarbonate commonly used as?
Magnesium carbonate, aluminum hydroxide, and sodium bicarbonate are commonly used as antacids. Give the empirical formulas and determine the molar masses of these compounds. Based on their formulas, suggest another compound that might be an effective antacid. ♦ Nickel(II) acetate, lead(II) phosphate, zinc nitrate, and beryllium oxide have all been reported to induce cancers in experimental animals.
What type of taste do bases normally have?
Bases often have a bitter taste and are found in foods less frequently than acids. Many bases, like soaps, are slippery to the touch.
Which body part helps roundworm prevent their body from expanding?
tough cuticle covering
Roundworms have a tough covering of cuticle on the surface of their body. It prevents their body from expanding. This allows the buildup of fluid pressure in their partial body cavity. The fluid pressure adds stiffness to the body. This provides a counterforce for the contraction of muscles, allowing roundworms to move easily over surfaces.
The maintenance of constant conditions in the body is also known as what?
Homeostasis, or the maintenance of constant conditions in the body, is a fundamental property of all living things. In the human body, the substances that participate in chemical reactions must remain within narrows ranges of concentration. Too much or too little of a single substance can disrupt your bodily functions. Because metabolism relies on reactions that are all interconnected, any disruption might affect multiple organs or even organ systems. Water is the most ubiquitous substance in the chemical reactions of life. The interactions of various aqueous solutions—solutions in which water is the solvent—are continuously monitored and adjusted by a large suite of interconnected feedback systems in your body. Understanding the ways in which the body maintains these critical balances is key to understanding good health.
What is the term for tough protein fibers that connects bones to each other?
Ligaments are made of tough protein fibers and connect bones to each other. Your bones, cartilage, and ligaments make up your skeletal system .
What is the study of macroscopic properties, atomic properties, and phenomena in chemical systems?
molecular chemistry
differential chemistry
thermal chemistry
physical chemistry
Physical chemistry is the study of macroscopic properties, atomic properties, and phenomena in chemical systems. A physical chemist may study such things as the rates of chemical reactions, the energy transfers that occur in reactions, or the physical structure of materials at the molecular level.
Bones, cartilage, and ligaments make up what anatomical system?
Muscular system
Integumentary system
Lymphatic system
skeletal system
The skeletal system is made up of bones, cartilage, and ligaments. The skeletal system has many important functions in your body. What bones protect the heart and lungs? What protects the brain?.
What is the first part of the large intestine called?
Cecum The first part of the large intestine is the cecum, a sac-like structure that is suspended inferior to the ileocecal valve. It is about 6 cm (2.4 in) long, receives the contents of the ileum, and continues the absorption of water and salts. The appendix (or vermiform appendix) is a winding tube that attaches to the cecum. Although the 7.6-cm (3-in) long appendix contains lymphoid tissue, suggesting an immunologic function, this organ is generally considered vestigial. However, at least one recent report postulates a survival advantage conferred by the appendix: In diarrheal illness, the appendix may serve as a bacterial reservoir to repopulate the enteric bacteria for those surviving the initial phases of the illness. Moreover, its twisted anatomy provides a haven for the accumulation and multiplication of enteric bacteria. The mesoappendix, the mesentery of the appendix, tethers it to the mesentery of the ileum.
What occurs when nature reclaims areas formerly occupied by life?
primary succession
typical succession
tertiary succession
secondary succession
Forest and Kim Starr (Flickr:Starr Environmental). Secondary succession occurs when nature reclaims areas formerly occupied by life . CC BY 2.0.
To solubilize the fats so that they can be absorbed, what organ secretes a fluid called bile into the small intestine?
small intestine
gall bladder
A related mechanism allows us to absorb and digest the fats in buttered popcorn and French fries. To solubilize the fats so that they can be absorbed, the gall bladder secretes a fluid called bile into the small intestine. Bile contains a variety of bile salts, detergent-like molecules that emulsify the fats.
When the hemoglobin loses its oxygen, it changes to what color?
light pink
purple red
grayish red
bluish red
The structure of heme (Figure 19.29), the iron-containing complex in hemoglobin, is very similar to that in chlorophyll. In hemoglobin, the red heme complex is bonded to a large protein molecule (globin) by the attachment of the protein to the heme ligand. Oxygen molecules are transported by hemoglobin in the blood by being bound to the iron center. When the hemoglobin loses its oxygen, the color changes to a bluish red. Hemoglobin will only transport oxygen if the iron is Fe2+; oxidation of the iron to Fe3+ prevents oxygen transport.
How are weather patterns formed?
the moon's gravitational pull
carbon dioxide
pollution from planes
uneven heating of the atmosphere
Weather refers to conditions of the atmosphere at a given time and place. It occurs because of unequal heating of the atmosphere. Humidity, clouds, and precipitation are important weather factors.
Boyle discovered that what property of a gas is inversely proportional to its volume?
in a one-liter container (Figure 22.15). In this case, the force exerted by the movement of the gas molecules against the walls of the two-liter container is lower than the force exerted by the gas molecules in the one-liter container. Therefore, the pressure is lower in the two-liter container and higher in the one-liter container. At a constant temperature, changing the volume occupied by the gas changes the pressure, as does changing the number of gas molecules. Boyle’s law describes the relationship between volume and pressure in a gas at a constant temperature. Boyle discovered that the pressure of a gas is inversely proportional to its volume: If volume increases, pressure decreases. Likewise, if volume decreases, pressure increases. Pressure and volume are inversely related (P = k/V). Therefore, the pressure in the one-liter container (one-half the volume of the two-liter container) would be twice the pressure in the two-liter container. Boyle’s law is expressed by the following formula:.
What amazing machines smash particles that are smaller than atoms into each other head-on?
absorption accelerators
nitrogen accelerators
observant accelerators
particle accelerators
Scientists have built machines called particle accelerators. These amazing tools smash particles that are smaller than atoms into each other head-on. This creates new particles. Scientists use particle accelerators to learn about nuclear fusion in stars. They can also learn about how atoms came together in the early universe. Two well-known accelerators are SLAC, in California, and CERN, in Switzerland.
The interaction of what opposite factors describe a biome and ecosystem?
hygroscopic and abiotic
metastasis and biotic
innate and biotic
abiotic and biotic
The abiotic factors, such as the amount of rainfall and the temperature, are going to influence other abiotic factors, such as the quality of the soil. This, in turn, is going to influence the plants that migrate into the ecosystem and thrive in that biome. Recall that migration is the movement of an organism into or out of a population. It can also refer to a whole new species moving into a habitat . The type of plants that live in a biome are going to attract a certain type of animal to that habitat. It is the interaction of the abiotic and biotic factors that describe a biome and ecosystem. In aquatic biomes, abiotic factors such as salt, sunlight and temperature play significant roles.
What is caused by differences in density at the top and bottom of the ocean?
flat currents
shallow currents
still water
deep currents
Currents also flow deep below the surface of the ocean. Deep currents are caused by differences in density at the top and bottom. More dense water takes up less space than less dense water. It has the same mass but less volume. Water that is more dense sinks. Less dense water rises. What can make water more dense?.
What is the layer of tissue between the body and shell called?
Mollusks have a hard outer shell. There is a layer of tissue called the mantle between the shell and the body.
Well suited to absorb water and dissolved minerals from the soil, thin-walled dermal cells and tiny hairs cover what basic plant structures?
Roots are covered with thin-walled dermal cells and tiny root hairs. These features are well suited to absorb water and dissolved minerals from the soil.
What is the major artery of the body, taking oxygenated blood to the organs and muscles of the body?
The Heart The heart is a complex muscle that consists of two pumps: one that pumps blood through pulmonary circulation to the lungs, and the other that pumps blood through systemic circulation to the rest of the body’s tissues (and the heart itself). The heart is asymmetrical, with the left side being larger than the right side, correlating with the different sizes of the pulmonary and systemic circuits (Figure 16.10). In humans, the heart is about the size of a clenched fist; it is divided into four chambers: two atria and two ventricles. There is one atrium and one ventricle on the right side and one atrium and one ventricle on the left side. The right atrium receives deoxygenated blood from the systemic circulation through the major veins: the superior vena cava, which drains blood from the head and from the veins that come from the arms, as well as the inferior vena cava, which drains blood from the veins that come from the lower organs and the legs. This deoxygenated blood then passes to the right ventricle through the tricuspid valve, which prevents the backflow of blood. After it is filled, the right ventricle contracts, pumping the blood to the lungs for reoxygenation. The left atrium receives the oxygen-rich blood from the lungs. This blood passes through the bicuspid valve to the left ventricle where the blood is pumped into the aorta. The aorta is the major artery of the body, taking oxygenated blood to the organs and muscles of the body. This pattern of pumping is referred to as double circulation and is found in all mammals. (Figure 16.10).
What do you call a growing mass of cancerous cells that pushes into nearby tissues?
Lung cancer is a disease in which the cells found in the lungs grow out of control. The growing mass of cells can form a tumor that pushes into nearby tissues. The tumor will affect how these tissues work. Lung cancer is the most common cause of cancer-related death in men, and the second most common in women. It is responsible for 1.3 million deaths worldwide every year ( Figure below ). The most common symptoms are shortness of breath, coughing (including coughing up blood), and weight loss. The most common cause of lung cancer is exposure to tobacco smoke.
What is the major intracellular cation?
Potassium Potassium is the major intracellular cation. It helps establish the resting membrane potential in neurons and muscle fibers after membrane depolarization and action potentials. In contrast to sodium, potassium has very little effect on osmotic.
The enzyme pepsin plays an important role in the digestion of proteins by breaking down intact protein to what short-chain amino acids?
Protein A large part of protein digestion takes place in the stomach. The enzyme pepsin plays an important role in the digestion of proteins by breaking down the intact protein to peptides, which are short chains of four to nine amino acids. In the duodenum, other enzymes— trypsin, elastase, and chymotrypsin—act on the peptides reducing them to smaller peptides. Trypsin elastase, carboxypeptidase, and chymotrypsin are produced by the pancreas and released into the duodenum where they act on the chyme. Further breakdown of peptides to single amino acids is aided by enzymes called peptidases (those that break down peptides). Specifically, carboxypeptidase, dipeptidase, and aminopeptidase play important roles in reducing the peptides to free amino acids. The amino acids are absorbed into the bloodstream through the small intestines. The steps in protein digestion are summarized in Figure 34.17 and Table 34.6.
What remains a constant of radioactive substance over time?
rate of decay
The rate of decay of a radioactive substance is constant over time.
Terrestrial ecosystems, also known for their diversity, are grouped into large categories called what?
Terrestrial ecosystems, also known for their diversity, are grouped into large categories called biomes. A biome is a largescale community of organisms, primarily defined on land by the dominant plant types that exist in geographic regions of the planet with similar climatic conditions. Examples of biomes include tropical rainforests, savannas, deserts, grasslands, temperate forests, and tundras. Grouping these ecosystems into just a few biome categories obscures the great diversity of the individual ecosystems within them. For example, the saguaro cacti (Carnegiea gigantean) and other plant life in the Sonoran Desert, in the United States, are relatively diverse compared with the desolate rocky desert of Boa Vista, an island off the coast of Western Africa (Figure 20.3).
High explosives create shock waves that exceed the speed of sound, a phenomenon that goes by what term?
light speed
ion speed
The modern day formulation of gun powder is called black powder. It is still commonly used today. Its formulation is still quite similar to what was used in 9 th century China. Black powder is considered a low explosive. It is a mixture that burns quickly, but the resulting shock wave travels at subsonic speeds. The speed at which it burns is dependent on the accessibility of oxygen atoms to the carbon source. In contrast, high explosives like nitroglycerin detonate instead of burning, creating shock waves that are supersonic (faster than the speed of sound).
What do you call a structure composed of two or more types of tissues that work together to do a specific task?
An organ is a structure composed of two or more types of tissues that work together to do a specific task. Most modern plants have several organs that help them survive and reproduce in a variety of habitats. Major organs of most plants include roots, stems, and leaves. These and other plant organs generally contain all three major tissue types.