according to the endosymbiotic theory, why was it adaptive for the larger cell to keep the engulfed cell alive rather than digestibg jt as food
the engulfed cell provided the host cell ATP
which of the following is an important role of fungi in the carbon cycle
fungi help release fixed carbon back to the environment for other plants and photosynthetic organisms to utilize
why do Na+ ions enter the cell when voltage-gated Na+ channels are opened in neurons
because the Na+ concentration is much higher outside the cel than inside, and the Na ions are attracted to the negatively charged interior
on a submarine expedition to the ocean bottom, you discover a population of fish that are only female. What type of reproduction does this fish use
what makes sexually reproduced offspring different from their parents?
genetic recombination during meiosis
which of the following best describes the process of ventilation?
the movement of air through lungs or gills
which of the following best describes the neuroendocrine-to-endocrine pathway of a hormone action
a neural organ that processes hormones regulates another gland through the release of hormones into the circulation that travel to the affected gland
in an animal that switches between sexual and asexual reproduction, when is sexual reproduction more likely to occur
when conditions for survival are unfavorable
why is it more difficult to obtain enough oxygen via respiration from water than from air
the density of water makes ventilating the respiratory tissues more difficult
a rabbit taken from a meadow near sea level and moved to a meadow high on a mountain side would have some trouble breathing. Why?
the partial pressure of oxygen in the air at high elevations is lower than at sea level
if you found a skull in the woods and teeth were fang-like, what type of food would you expect this animal to eat?
the flesh of another animal
what is the difference between viviparous and ovoviviparous species?
ovoviviparous species receive nourishment from yolk in the egg and the viviparous species receive nourishment from the mothers circulatory system
which of the following is similar in structure to cholesterol?
testosterone, estradiol, and cortisol
what can the mouthparts of an animal tell you about its diet?
mouthparts are specialized to obtain desired food items efficiently
what is the function of the cochlea?
the amplify the sound vibrations and collect sound pressure waves
how would the vision of a fly be affected is several of the axons extending from the ommatidia of its compound eye were damaged?
the fly would have reduced resolution in the affected eye
the concentrations of ions are very different inside and outside a nerve cell due to
when you are jogging, your muscles are using more oxygen and releasing more carbon dioxide into the blood than you are when you are home on the couch. which of the following would occur during your jog?
the medullary respiratory center would increase the rate of breathing
why does external fertilization typically occur much more often in aquatic animals than in terrestrial animals?
the gametes must be kept wet to avoid desiccation
which of the following correctly describes a difference between spermatogenesis and oogenesis?
spermatogenesis results ib 4 mature sperm cells, while oogenesis results in one mature egg cell
why is pharmacological reactivation of fetal hemoglobin in a patient with sickle cell anemia often a successful treatment?
fetal hemoglobin has a high affinity for oxygen than adult hemoglobin
what is the purpose of villi and microvilli in the small intestine
the villi and microvilli increase the surface area to increase the efficiency of nutrient absorption
what is the importance of mucins that are released by the salivary glands?
they are glycoproteins that make food slippery enough to slide down the esophagus
what would probably happen is a long neuron had one continuous mylen sheath down the length of the axon with no nodes of Ranvier?
the signal would fade because it is not renewed by the opening of more sodium channels
aquaporins have been identified in the epithelium of the large intestine. What is the function of these aquaporins?
to reabsorb water from the large intestine
the function of mechanical digestion is to break down large chunks of food into smaller pieces. Why is this important?
smaller pieces of food have more surface area for chemical digestion than do larger pieces of food
how does lymph differ between closed and open circulatory systems?
in a closed system, lymph travels through a set of vessels separate from the blood, whereas in an open system, they never separate
what would happen to people exposed to a chemical warfare agent that blocked acetylcholine from binding to muscle receptors?
muscle contractions would be prevented causing paralysis
the main difference between respiration in terrestrial insects and terrestrial vertebrates is that
insects rely on their tracheal system to deliver oxygen to their tissues, whereas terrestrial vertebrates rely on their lungs to deliver oxygen to their tissues through the blood in their circulatory system
what is the importance of consuming an adequate amount of proteins in the diet?
proteins serve a variety of functions, and the body does not store excess quantities of protein
aquatic animals that rely on fertilization for reproduction have a low probability of successful fertilization. which one of the following is not used by aquatic animals to increase the success of external fertilization?
moving onto land for fertilization
removing which of the following glands would have the most wide-reaching effect on bodily functions of an adult human?
what adaptations are observed in trachea and lungs to reduce water loss?
the location of trachea and lungs inside of the the body reduce water loss
what is the only type of chemical signal that does not intend to alter the physiology of the animal producing that signal?
a salmon follows a scent trail upstream to find its way back to the stream where it hatched. What type of sensory receptor cell would it use?
when a person drinks alcohol the rate of urination increases. This suggests that antidiuretic hormone (ADH) may be affected by alcohol consumption in some way. Which of the following could account for the increase in urination?
alcohol inhibits the release ADH
what property of the steroid hormones allows them to cross the phospholipid bilayer?
steroid hormones are lipid soluble and easily cross the phospholipid bilayer
How do myelin sheaths increase the speed with which action potentials are propagated along an axon?
they cause action potentials to "jump" down the axon rather than travel n a continuous oath along every site on the axon
animals that have external fertilization are more likely to reproduce in which of the following areas?
if other factors are equal, which of the following environments would have the highest level of dissolved oxygen?
cool freshwater at low elevation
in an area with a high abundance of algal blooms, the introduction of _______ might alleviate the severity of the blooms
to establish a link between specific bacterium and a skin disease, researchers have shown that bacterium was present in sick persons but not in healthy individuals. They isolated the bacterium in a pure culture and demonstrated that experimental healthy animals injected with this culture came back sick. What other experiment do researchers need to perform to be absolutely sure about the bacterium is responsible for the disease?
isolate the bacterium from infected sick animal and demonstrate that it is the same bacterium as the one used for infection
plants re the primary providers of oxygen, which is obtained by the reduction of carbon dioxide. What chemical donates the electrons needed for CO2 reduction?
a particular species of protist has obtained a chloroplast via secondary endosymbiosis. How can you tell?
the chloroplasts have 3 or 4 membranes
to reproduce, many plants produce seeds - structures containing embryonic offspring along with nutrients inside a tough case. These offspring develop after being released by the parent plant. To which animal reproductive strategy is seed production most comparable?
which of the following is true of stomata
stomata open to allow gas exchange and close to decrease water loss
evolutionarily speaking, what is the benefit of complete metamorphosis over incomplete metamorphosis?
offspring do not compete with adults for food
what is believed to be the most significant result of the evolution of the amniotic egg?
tetrapods were no longer tied to water for reproduction
This group of fungi has the ability to penetrate its host cell wall, thus increasing the efficiency with which materials are passed from fungus to host
arbuscular mycorrhizal fungi
you find a green organism in a pond near your house and believe it is plant, not alga. Which line of evidence would definitively support your hypothesis
it is surrounded by a cuticle
biologists sometimes divide living organisms into 2 groups: autographs and heterotrophs. How do these 2 groups differ?
they use different sources of carbon
according to the fossil record, plants colonized terrestrial habitats
in conjunction with fungi that helped provide them with nutrients from soil
you observe the gametes of a fungal species under the microscope and realize they resemble animal sperm. to which of the following groups does the fungus belong?
To colonize, land plants had to overcome a number of difficulties. However, once this occurred they were able to exploit more abundant resources. Which of the following resources were more plentiful on land than in water
fungi have extremely high surface-area-to-volume ratio's. What is the advantage of this to an organism that gets most of its nutrition through absorption?
the larger surface area allows for more material to be transported through the cell membrane
why is it important that ectomycorrhizal fungi (EMF) have peptidase enzymes?
These enzymes are needed to release nitrogen from dead plant material in colder environments
what would be the results if a tunicate's pharyngeal gill slits were suddenly blocked
the organism would have trouble respiring and feeding
why are mycorrhizal fungi superior to plants at acquiring mineral nutrition from the soil?
fungi secrete extracellular enzymes that can break down large molecules
What do biologists cite as the primary benefit of the evolution of a coelom in animals?
the hydrostatic skeleton, allowing greater range of motion
what unique "process" allow sea cucumbers (echinodermata: Holothuridea) to eviscerate their guts to avoid predators?
mutable connective tissue
About 450 million years ago, the terrestrial landscape on Earth would have
had non-vascular green plants similar to liverworts forming green mats on rock
In examining an unknown animal species during it embryonic development, how can you be sure what you are looking at is a protostome and not a deuterostome?
you see a mouth, but not an anus
The evolution of animal species has been prolific (the estimates go into the millions and tens of millions). Too what does the text attribute much of this diversity?
a large variety of methods for capturing and processing food
what evidence do paleobotanists look for that indicates the movement of plants from water to land?
waxy cuticle to decrease evaporation from leaves
What two major novelties allowed for the first colonization of terrestrial habitats by plants
cuticle and pores
Microbiologists use the gram stain to aid in the identification of bacteria. What is the major difference between gram-positive and gram-negative bacteria
presence or absence of outer plasma membrane
Encouraging the growth (via nutrient fertilization) of photosynthetic protists in marine environments may help reduce global warming. Why?
because photosynthetic protists fix atmospheric carbon dioxide, decreasing atmospheric CO2 levels
while examining a rock surface, you have discovered an interesting new organism. Which of the following criteria will allow you to classify the organism as belonging to Bacteria but not Archaea or Eukarya?
cell walls are made primarily of peptidoglycan
Bioprospectors and athnobotanists search for plants and plant products used for medicines by native cultures. The major function of the medicinal compounds in plants is to
defend the plant against herbivores
Alteration of generations occur in some protists. Which of the following represents the correct sequence of events for this mode of reproduction?
gametophyte -> gametes -> fusion -> sporophyte -> spore -> gametophyte
which of the following is a characteristic of all chordates at some point during their life cycle?
Which of the following is true for both arthropod exoskeletons and mollusk shells?
They help retain moisture in terrestrial habitats
_____ Led to mammals and birds having similar insulating skin coverings such as fur, hair, and feathers.
Primate evolution and behavior - such as hunting skills - has been directed in part by the development of depth perception. What anatomical change made depth perception possible?
movement of the eyes to the front of the head
Which of the following molecules acts similarly to applying direct pressure to a wound to close blood vessels?
You are playing a new video game that is based on the human immune system. The player is inside a human, and you must successfully fend off invading pathogens in a quest to find the "Golden Antibody." At level 1, your arsenal for fighting off pathogens consists only of the innate immunity leukocytes and their various secretions. If the enemy has killed off most of your neutrophils and macrophages, which of the following should you utilize to recruit more of these leukocytes to the battle?
If a patient only has neutrophils and macrophages, what would be absent from the immune response?
Which of the following would put you at increased risk of pathogens entering your body?
a mutation that causes your mucus secretions to be extremely watery
Which of the following is most accurate regarding blood vessels leading to a fresh wound?
Vessels are constricted near the wound and dilated farther away.
You and a friend are in line for a movie when you notice the woman in front of you sneezing and coughing. Both of you have been equally exposed to the woman's virus, but over the next few days, only your friend acquires flu-like symptoms and is ill for almost a week before recovering. Which one of the following is a logical explanation for this?
You have an adaptive immunity to that virus
Mucus occurs in both the respiratory and digestive tracts. What is its main immunological function?
physically trapping pathogens
Mast cells are primarily responsible for swelling at the site of an infection due to the secretion of which signaling molecule?
A boy falls while riding his bike. A scrape on his hand almost immediately begins to bleed and becomes red, warm, and swollen. What response is occurring?
Mast cells can both constrict and dilate blood vessels after injury. Which of the following best explains why both of these events occur shortly after tissue is injured?
Mast cells release different chemical messengers, one that causes constriction in the region of blood loss, and another that causes dilation away from the injury to promote quicker healing.
You cut your finger, and after putting pressure on the wound for several minutes, you notice that it is still bleeding profusely. What may be the problem?
Platelets are not functioning properly, or there are too few to be effective.
Which of the following is the best definition of autoimmune disease?
a condition in which the self molecules are treated as non-self
What major advantage is conveyed by having a system of adaptive immunity?
It enables a rapid defense against an antigen that has been previously encountered.
What is responsible for the activation of lymphocytes?
encountering the specific antigens to which they are programmed to respond
What is the difference between a B-cell receptor and an antibody?
Antibodies lack a transmembrane domain.
B cells and T cells have variable receptors that allow them to recognize virtually any epitope. What is responsible for this diversity?
The acquired response differs from the innate response based on which of the following attributes?
specificity of the response
Which of the following statements is not true of epitopes?
There is a one-to-one correspondence between antigen and epitope.
Which of the following is a difference between B cells and T cells?
One has a major role in antibody production, while the other has a major role in cytotoxicity.
Which of the following is crucial to activation of the adaptive immune response?
presentation of MHC-antigen complex on a cell surface
Considering chemotherapy is designed to target rapidly dividing cells, which process would be most impacted?
What causes rejection by the body's immune system after a transplant of an improperly matched organ?
non-self proteins in the tissue, the presence of foreign MHC proteins on the donor tissue, and antibodies and cytotoxic T lymphocytes (CTLs) responding to foreign tissue
Which of the following is true of the allergic response?
Sufferers produce the IgE class of gamma globulins in response to allergens.
Which would occur if blood vessels did not dilate in response to a wound?
Cell debris would not be removed efficiently.
Biologists study how nutrients and energy move among organisms and through water, soil, and air. Which level of ecological study is this?
It is ecosystem ecology.
Which abiotic factor would have the most significant physiological effect on migrating salmon?
water solute content
In deep water, which of the following abiotic factors would most limit productivity?
Where would you expect to find photosynthetic organisms at the greatest depth and why?
freshwater, because there are fewer solutes to refract the light
Why are fish found in cold, fast-moving streams more active than those in warm, slow-moving streams?
Cold, fast-moving areas are rich in oxygen
A fish swimming into an estuary from a river would have which of the following as its greatest physiological challenge?
The change in water solute content would challenge the osmotic balance of the fish.
A fish species known for its success in the aphotic zone would likely not have which of the following characteristics?
symbioses with photosynthetic organisms
Which freshwater environment is characterized by low pH, lack of nitrogen, and anoxic conditions, making it relatively unproductive?
Wetlands are standing bodies of freshwater, just like lakes and ponds. However, wetlands are different from lakes and ponds because _____.
wetlands have shallow water and emergent vegetation
The carnivorous pitcher plant is successful in bog habitats because _____.
it has a strategy to get nitrogen, which gives it a competitive advantage
which criteria allow biologists to divide chemicals into macronutrients and micronutrients
the quantities required by the plant
which term best describes an animal that although generating a significant amount of heat through metabolism, nonetheless does not maintain constant body temp
one of the waste products that accumulates during cellular functions is carbon dioxide. It is removed via the respiratory system. What is another waste product that accumulates during normal physiological functions in vertebrates
ammonia, uric acid, urea
which of the following experiments is able to determine if an element is essential for plant growth
growth of hydroponics without the element
will treating a viral infection with antibiotics affect the course of the infection?
no, antibiotics do not kill viruses because viruses use host cell proteins to replicate and antibiotics affect bacterial
what is the trade off in nutrient avaliability concerning clay soils
cations are less likely to leach out of soil but are difficult for plants to extract
some animals have no gills when young but then develop gills that grow larger as the animal grows larger. Whats the reason for the gill size?
relative to their volume, the young have more surface area across which they can transport the oxygen
when an animal cell is placed in a hypotonic solution and water enters the cell via osmosis, the volume of the cell increases until it bursts. This doesnt happen in plant cells because
they have cell walls, which provide pressure to counteract the pressure of the incoming water
what major benefits do plants and mycorrhizal fungi receive
plants get N and P, fungi recieve photosynthetic products
which of these structure-function pairs is incorrect?
cuticle - layer of cells where light reactions occur
The driving force for simple diffusion is _____ while the energy source for active transport is____
concentration gradient, ATP
What is the main structural difference between enveloped and non-enveloped viruses?
enveloped viruses have a phospholipid membrane outside their capsid, whereas non-enveloped viruses do not
what is the function of proton pumps localized in the plant plasma membrane
to create membrane potential
which of the following structural features of epithetial cells are related to the function?
they have polarity
which type of modified stems are typical of plants that historically have needed to protect themselves
what soil composition would be best for availability of nutrients, water, and root development
high humus, low sand and clay
freshwater fish are hypertonic compared to their environment. To maintain homeostasis in this environment they must
excrete large quantities of water
Plants produce more seeds when they reproduce asexually. Yet most plants reproduce sexually in nature. What is the probable explanation for the prevalence of sexual
sexual reproduction mixes up alleles contributing to variation in species
which of the following features of plants allows for symplastic movement of water
plasmodesmata and casparian strip
it is estimated that animal pollinated plants produce 1,000 pollen grains for each ovule; wind pollinates produce 100,000. What does this indicate
wind pollination is less efficient than animal
The loop of henle dips into the renal cortex. This is an important feature of osmoregulation in terrestrial vertebrates because
different permeabilities of ascending and descending limbs of the loop of henle are important in establishing an osmotic gradient
home flower gardeners in northern latitudes like to grow plants that flower only in the spring. thr plants are more sensitive to
a summer at corn belt....what does this tell you about corn
the flowers are imperfect and the plant is monoecious
you observe a lizard sitting on the shore on a sunny day. If the lizard is attempting to raise its body temp what type of heat transfer is being employed
plant leaf epidermal cells have an array of trichomes. what is the normal function of trichomes?
open and close for gas exchange