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Which type of molecular evidence is most useful in determining how Bacteria, Eukarya, and Archea are all related?
Which portion of the tree may ultimate be better depicted as a "ring"?
the weblike part near the base of the tree
Many homeowners mow their lawns during the summer and collect the clippings, which are hauled to the local landfill. Which of the following actions would most benefit the local ecosystem (i.e. the yard)?
either collect the clippings and add them to a compost pile, or don't collect the clippings and let them decompose in the lawn
Aquatic primary productivity is most limited by which of the following?
light and nutrient availability
A porcupine eats 3000J of plant material. 1600J is indigestible and is eliminated as feces. 1300J are used in cellular respiration. What is the approximate production efficiency of this animal?
3% or 10%
In the third Jurrasic Park movie, the scientists commented that there were far too many predators on the island. This was true because
Energy transfer between trophic levels is usually only 10%, and therefore limits the number of larger predators that feed higher up on the food chian
______ has been eliminated from laundry detergents after studies showed that it cause algal blooms.
Which of the following statements is correct about biogeochemical cycling?
The phosphorus cycle is the cycle that involves weathering of rocks.
Natural terrestrial Ecosystems are generally green because herbivores are held in check by all of the following, except ______
What would be a likely entry for box B?
decomposer population carries on cellular respiration and uses up oxygen
The high levels of pesticides found in birds of prey (i.e. eagles, gulls) is an example of
Agricultural lands frequently require nutritional supplementation because
the nutrients that enter the plants are not returned to the soil of lands where they are harvested
Which of the following is NOT true regarding increased atmospheric CO2 levels?
Scientists are in agreement that increased CO2 levels are causing global warming
Aside from CO2 emissions, we are also concerned about the emission of ______ gases since they cause _______, thereby causing a negative impact on ecosystems.
NO and SO2; acid rain
Which of these is the most common compound in the cell walls of gram-positive bacteria
Not present in all bacteria, this structure enables those that possess it to germinate(grow) after exposure to harsh conditions, such as drying out completely:
Which of these can be inferred from the figure?
The highest rate of genetic change occurred during the first quarter of the experiment
Assuming that each of these possesses a cell wall, which prokaryotes should be expected to be most strongly resistant to plasmolysis (i.e. cell bursting) in hypertonic (very salty) environments?
The data were collected from the heterocytes of a nitrogen fixing cyanobacterium inhabiting equatorial ponds. Study the graph below and choose the most likely explanation for the shape of the curve.
Enough O2 enters heterocytes during hours of peak photosynthesis to have a somewhat-inhibitory affect on nitrogen fixation
What is "biofilm"?
a group of different bacterial species that coat moist surfaces, creating a metabolic cooperation
Many physicians administer antibiotics to patients at the first sign of any disease symptoms. Why can this practice cause more problems for these patients, and for others not yet infected?
Overuse of antibiotics can select for antibiotic-resistant strains of bacteria
The strongest evidence for the endosymbionic origin of eukaryotic organelles is the similarity between extant prokaryotes and which of the following?
mitochondria and chloroplasts
Which organism represent the common ancestor of all photosynthetic organelles found in eukaryotes?
A biologist discovers a new unicellular organism that possesses more than two flagella and two small, equal-sized nuclei. The organism has reduced mitochondria and no chloroplasts. To which clade does this organism probably belong?
Which of these taxa contains species that produce potent toxins that can cause extensive fish kills, contaminate shellfish, and poison humans?
The organism that causes malaria, _____, is a member of the Phylum ______.
Which of the following pairs of protists and their characteristics is mismatched?
ciliates : Red tide organisms
The most recent common ancestor of all land plants was probably similar to modern day members of which group?
To deal with animal predation, the early Pterophytes evolved
multiple sporophytes growing from each gametophyte
Which of the following most closely represents the male gametophyte of seed-bearing plants?
pollen grain interior
Hypothetically, one of the major benefits of double fertilization in angiosperms is to
coordinate developmental timing between the embryo and its food stores
Many mammals have skins and mucous membranes that are sensitive to phenolic secretions of plants like poison oak (Rhus). These secondary compounds are primarily adaptations that
In addition to seeds, which of the following characteristics are unique to only the seed-producing plants?
If a fruit is covered with spines or hooks, it is most likely dispersed by
animal skin, fur, or feathers
You can find a plant with parallel veins in its leaves. This plant most likely belongs to the Class ________
The number of legs an insect has, the number of vertebrae in a vertebral column, or the number of joints in a digit (such as a finger) are all strongly influenced by
You are trying to identify an organism. It is an animal, but it does not have nerve or muscle tissue. It is probably a
A student encounters an animal embryo in the eight-cell stage. The four smaller cells that comprise one hemisphere of the embryo seem to be rotated 45 degrees and lie in the grooves between larger, underlying cells (spiral cleavage). This embryo may potentially develop into a(n)
If we were to separate these eight cells and attempt to culture them individually, then what is most likely to happen?
Each cell my continue development, but only into a non-viable embryo that lacks many parts
While sampling marine plankton in a lab, a student encounters large numbers of fertilized eggs. The student rears some of the eggs in the laboratory for further study and finds that the blastopore becomes the mouth. The embryo develops into a trochophore larva and eventually has a true coelom. These eggs probably belonged to a
Which cells in a sponge are primarily responsible for trapping and removing food particles from circulating water?
In a small stream, you pick up a rock and observe many small, flattened worms crawling on its undersurface. You decide that they belong to the phylum Platyhelminthes. To which class to they probably belong?
Some species of which of the following annelid classes release an anticoagulant that is of medical importance?
The heartworms that can accumulate within the hearts of dogs and other mammals have a pseudocoelum, an alimentary canal, and an outer covering that is occasionally shed. To which phylum does the heartworm belong?
The organisms in the Phylum _______ lack ______, and might better be classified within the Protostome clade.
Aceola, a coelom
Ectoprocts are also known as Bryozoa (moss animals) because
their extended lophophore during feeding make them look like a fuzzy underwater moss
Nudibranchs are marine slugs that have lost their shell (similar to land slugs). However, the tissue that normally makes the shell still exists but is modified as a way to perform gas exchange. This tissue is also called the ____
Which extant chordates are postulated to be most like the earliest chordates in appearance? In other words, which one of the following has only the four basic chordate characteristics?
Terry catches an animal from the Class Osteichthys from the ocean and notices that, attached to its flank, there is an equally long, snakelike organism. The Osteightyhys looks frail and sickly, almost dead. The attached organism has no external segmentation, no scales. a round mouth surrounded by a sucker and two small eyes. Terry thinks it might be a marine leech, a hagfish, or a lamprey. Which feature excludes it from possibly being a leech?
its lack of segmentation
Terry detaches the snakelike organism from the fish and uses a knife to cut off its head, in doing so, its brain slides out onto the deck of the boat. Terry peers into the cut end of the head and notices that the brain had lain in a sort of pan-like structure that only partially surrounded the brian. What is the structure Terry is observing?
Having caught and handled a hagfish, what will Terry's shipmates most likely require Terry to do before returning to further fishing?
Clean the bucketsful of hagfish slime from the deck of the boat
According to one hypothesis, the jaws of vertebrates were derived by the modification of
skeletal rods that had supported the pharyngeal (gill) slits
What permits reptiles to thrive in arid environments?
their scales contain the protein keratin, which helps prevent dehydration
During chordate evolution, what is the sequence (from earliest to most recent) in which the following structures arose?
jaws, paired fins, swim bladder, amniotic egg, diaphragm
The tissue type responsible for covering or lining the organs and coelum is the ____ tissue
You gently pull up the skin on the back of your hand. It can only stretch a certain distance because the non-elastic _______ will not allow you to pull it any further
In the DVD "Homeostasis," at the beginning of the race the hormone _______ was responsible for _______
epinephrine; increased heart rate
In the DVD "Homeostasis," assume Martina's hear rate was 120 bpm, her stroke volume was 100mL, and her blood pressure was 130/70. What was her Cardiac Output in mL/min?
Some scientists believe that tuna fish are warm blooded. This is
true, because the heat generated by its constantly moving muscles keeps it warm
The normal range of blood glucose is 90-100 mg/dL, but if the blood glucose levels rise beyond this level, the hormone _____ is released.
A patient who is not receiving all their essential Amino Acids likely will have problems with, or will have the condition known as
brittle nails and hair that is falling out
In terms of excess, which nutrient is most likely to accumulate in the body and cause overdoses
Pre-natal vitamins contain high levels of _____, which is critical in DNA and protein synthesis
Dr. O's son loves his pirate ship toy, which is names "Scurvy Dog." Scurvy refers to the condition which plagued many sailors in the 1700's and 1800's where the lack of vitamin __, a crucial co-factor in collagen synthesis, was lacking from the sailor's diets.
Warfarin is an excellent anti-coagulant drug that at low doses is pharmacologically effective at preventing heart attack and stroke, but at high doses is a rat poison. Warfarin targets
The signal that food has entered the stomach and that the stomach should start churning harder and making gastric juices is the hormone
Pancreatic enzymes are not activated until ____ is converted to its active form in the _________.
trypsinogen; small intestines
What is enterohepatic recirculation?
xenobiotics in food --> intestines --> liver --> bile --> intestines --> liver, etc.
The vessel leaving the right ventricle in humans has several names. One of them is the
In an EKG, the QRS complex represents the
electrical firing of the AV node, Purkinje fibers, and Bundles of His
The ______ node fires first to give a time-delay to the _____ done to coordinate the contraction of the atria and ventricles.
What two factors affect the inward flow of interstitial fluids into a capillary at the venous end of a capillary bed?
low capillary hydrostatic pressure and high capillary osmotic pressure
One important function of the arterioles is to
regulate blood flow through capillary beds using precapillary sphincters
Rachel measured her blood pressure before exercise (110/73) and immediately after exercise (124/74). These measurement are
normal, since diastolic pressure stayed just about the same, but systolic pressure increased to compensate for her increased need for oxygen-delivery during exercise
A patient has the left side of her face drooping, her left arm is week, and she has hypertension. Likely what happened was that
she had a stroke, blocking a blood vessel to her brain
The hormone erythropoietin is released when you hike to high altitudes. This hormone
increases the production of erythrocytes
The first step in sealing a small break in a blood vessel is the formation of ________. Usually, this is all that is needed to seal the break.
a platelet plug
LDL-cholesterol is considered ______ since it ________.
lousy; transports cholesterol to the blood stream
Congestive heart failure occurs when
the heart enlarges due to pumping against an afterload, ultimately leading to less coordinated myocardial contractions
Hypertension if often associated with a condition where
a plaque of lipids, connective tissues and inflammation partially block arteries
Gills in fish, lungs in frogs, and lungs in birds are all respiratory surfaces. They share two traits:
moist surface; large surface area
You are holding your preath for a very long period of time, and begin to feel that urge to breathe. This urge is triggered by
high levels of CO2 in the bloodstream
Air rushes into the lungs of humans during inhalation because
the rib muscles and diaphragm contract, increasing the lung volume
Oxygen is transported primarily from the lungs to the tissues by being bound to
hemoglobin inside erithrocytes
After completing your BS degree in a Science field, NASA recruits you to help them explore a newly discovered planet that might be able to sustain life. Their data indicates that the atmosphere on this planet is 50% oxygen, 25% nitrogen, and 25% helium. The total atmospheric pressure is 500mmHg. What is the partial pressure of oxygen on this new planet's atmosphere in mmHg.
The hemoglobin )Hb) dissociation curve shows that
oxygen is bound to Hb at low PO2 (20 mm Hg) and is released at high PO2 (100 mmHg)
Some human infants, especially those born prematurely, suffer serious respiratory failure. This probably relates to which of the following?
the sudden change from the uterine environment to the air
Which molecule is excreted mostly by aquatic animals because of its solubility and toxic properties?
Materials are returned to the blood from the filtrate by which of the following processes?
Processing of filtrate in the proximal and distal tubules accomplishes what important function?
pumping metabolized xenobiotics into the filtrate
What is unique about transport epithelial cells in the upper 2/3 of the ascending loop of Henle in humans?
their membranes are impermeable to water
How does ADH function at the cellular level?
It causes an increase in the number of aquaporin molecules of collecting duct cells
Which one of the following, if present in a urine sample, would likely be caused by trauma (i.e. physical damage)?
What is urea trapping?
Maintaining moderate levels of urea in the renal medulla region to aid in creating a strong osmotic gradient
What would account for increased urine production as a result of drinking alcoholic beverages?
inhibition of antidiuretic hormone secretion (ADH)
Only certain cells in the body are target cells for the hormone aldosterone. Which of the following is the best explanation for why these are the only cells that respond to this hormone?
only target cells contain receptors for aldosterone
Why is it that some body cells respond differently to the same peptide hormones?
A target cell's response is determined by the product of a signal transduction pathway
When an individual is subject to short-term starvation, most available food is used to provide energy for the brain rather than building blocks (growth and repair) for the rest of the body. Which hormone would be particularly active in times of food storage?
The hypothalamus controls the anterior pituitary by producing _____, which are released into the blood stream
Which combination or hormones helps a mother to produce milk and nurse her baby?
oxytocin and prolactin
Tropic hormones from the anterior pituitary directly affect the release of which of the following?
All of the following are steroid hormones except?
Estrogen, Progesterone, Testosterone, and Cortisol are all steroid hormones
What happens when beta cells of the pancreas release their hormone into the blood?
Body cells take up more glucose
A 50 year old patient is complaining about being cold all the time, not being able to finish tasks due to lack of concentration, and a recent weight gain of 15 pounds in about 1 month. An Endocrinologist would likely check to see whether she is
Which of the following statements about the adrenal gland is correct?
During long-term stress, ACTH stimulates the adrenals. During short-term stress, neurons stimulate the adrenals
A 25 year old patient with type I diabetes mellitus (T1DM) likely has __________.
an autoimmune disease
A 40 year old male patient has unusually high levels of GnRH. This means that
he likely has very high levels of FSH and LH as well
A patient with untreated Diabetes mellitus (either type 1 or 2) will likely suffer from _________, due to their Diabetes.
increased intraocular pressure, leading to blindness
A Diabetes mellitus patient takes too much insulin. Their symptoms will be very similar to someone who has ____________.
consumed too much alcohol and is inebriated
The primary response to Leydig cells to the presence of luteinizing hormone (LH) is an increase in the synthesis and secretion of
The secretion of follicle stimulation hormone (FSH) from the pituitary is reduced by high levels of
Sertoli cells secrete ___________, which is similar to _____________ cells, which secrete the same hormone.
In humans, follicular cells that remain behind in the ovary after ovulation become
a steroid hormone synthesizing structure
In vertebrate animals, spermatogenesis and oogenesis differ in that
cytokinesis is unequal in oogenesis, whereas it is equal in spermatogenesis
In correct chronological order, the three phases of the ovarian cycle are
follicular --> ovulation --> luteal
A contraceptive pill that continuously stops the release of GnRH from the hypothalamus will
reduce the secretion of gonadotropins from the pituitary gland
The primary function of the corpus luteum is to
maintain progesterone and estrogen synthesis after ovulation has occurred
The reliable "marker" that a pregnancy has been initiated (detectable in urine) is
human chorionic gonadotropin
Contact of sperm with signal molecules in the coat of an egg causes the sperm to undergo
the acrosomal reaction
The sequence of developmental milestones proceeds as follows:
cleavage --> morula --> blastula --> gastrula
In human development, the risk of miscarriage sharply increases near the end of the first trimester for a short period of time (one to two weeks). This is die to _________
decreading hCG production, with a switch to Estrogen and Progesterone production by the fetus
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