What is the driving force for evolution, as it pertains to "new" structures within population?
Animals with mutations that give rise to effective structures will become more abundant
Why have diverse animals such as sharks, and pengins evolved similar fusiform body?
The laws of physics constrain the shapes that are possible for aquatic animals that swim very fast.
Why do multicellular organisms need their cells to be in a liquid medium?
Multicellular organisms must keep their cells awash in an internal pond because cells need an aqueous medium for the exchange of nutrients, gases and wastes.
An ectotherm is more likely to survive an extended period of food deprivation than would an equally-sized endotherm because?
The ectotherm invests little energy in temperature regulation.
Metabolism of specialized brown fat depots in certain animals is substantially increased during
Non-shivering thermogenesis (fat = highest energy output)
An animal that migrates great distances would obtain the greatest benefit form storing its energy as
Which Vitamins are deadly at high amounts?
A, D, E, K (Fat solubles) Essential amino acids, essential fatty acids, vitamins, minerals.
What animals and/or insects have a crop?
Earthworms, grasshoppers and birds. Used for temporary storage of food, food storage for nestlings, and production of crop milk.
Why are cattle able to survive on a diet consisting almost entirely of plant material?
They have cellulose-digesting, symbiotic microorganisms in chambers of their stomachs.
In which animals would you expect to find an enlarged cecum?
Rabbits, horses, and herbivorous bears.
What is a gizzard?
Muscular stomach chamber that uses ingested pebbles to pulverize food, some food storage which cehmical digestion that was begun in the proventriculus continues.
Organism in which a circulating body fluid is distinct from the fluid that directly surrounds the body's cells are likely to have what?
A closed circulatory system.
Difference between large molluscs and smalll molluscs (Circulatory system)
Open system in small molluscs
Close system in large molluscs
In which animal does bllod flow from the pumocutaneous circulation to the heart before circulating through the rest of the body?
What is the only vertebrate in which blood flows directly from respiratory organs to body tissues without first returning to the heart?
What's the significance of the ruman as it pertains to cellulose digestion?
The most symbiotic organism.
What organic materials are mammals able to digest and/or produce with the help of microorganisms?
Cellulose to simple sugars
What is an example of countercurrent exchange?
The flow of water across the gills of the fish and that of blood within those gills
How does hemocyanin of arthropods and mooluscs differ from the hemoglobin of mammals?
Hemocyanin has protein couples to copper rather than iron.
Marin sea star was mistakenly placed in freshwater and it died. What is the most likely explanation for its death?
The sea star is hyperosmotic to the freshwater, and it could not osmoregulate.
Organisms in which a circulating body fluid is distinct from the fluid that directly surrounds the body's cells are likely to have what?
A closed circulatory system.
How do birds live off of sea water?
Marine birds utiliza their nasal glands to eliminate excess salt from the body. (Same with sea turtles and marine iguanas)
Shark osmoregulate by
Tolerating high urea concentrations that balance internal salt concentrations to sea water osmolarity.
The advantage of excreting wastes as urea rather than as ammonia is that
Urea is less toxic than ammonia
Birds secrete what?
Birds secrete uric acid as their nitrogenous waste because uric acid requires little water for nitrogenous waste disposal, which is conductive to the function of flight in terms of weight.
Unlike an earthworm's metanephridia, a mammalian nephron...?
receives filtrate from blood instead of coelomic fluid
American lungfish, which are often found in small stagnant pools of fresh water, produce urea as a nitrogenous waste. What is the advatage of this adaptation?
Small stagnant pools do not provide enough water to dilute the toxic ammonia.
4th chamber heart made of contractile cardiac muscle downstream side of the ventricle. (lamprey, sharks, early bony fishes, lungifhses, and amphibians)
4th chamber heart made of contractile cardiac muscle in "higher" bony fishes (teleosts)
What group consists of deuterostomes
Echinoderms, fish, amphibian, reptiles, birds, mammals. (chordates)
In which animal does blood flow from the pulmocutaneous circulation to the heart before circulating through the rest of the body
Which vacationing in a country that lacks adequate meat inspection, a student ate undercooked ground beef. Sometimes later the student became easily fatigued, and lost body weight. At about the same time, whitish, flattened, rectangular objects full of small white spherees started appearing in his feces. Administration of niclosamide cured the problem.
Foramen of panizza
A unique anstomosing connection between the two aortic arches that aid in high level activity in a systemic circulation, which requires a large amount of oxygen in the blood.
The heartworm that can accumulate within the hearts of dogs and other mammals have a pseudocoelom, an alimentary canal, and an outer covering that is occasionally shed. To which phylum does the heartworm belong?
How does the hemocyanin of arthropods and molluscs differ from the hemoglobin of mammals
Hemocyanin has copper instead of iron
What is hemoglobin and which animals have them?
The respiratory pigment of almost all vertebrates and a wide variety of invertebrates is the protein hemoglobin, which is coupled with iron rather than copper
During countercurrent exchange of gasses, what percent of oxygen is present in the oxygenated blood that is returned to the body?
What are parabronchi?
Lungs of birds channel air through very tiny air vessls called parabronchi, where gas exchange actually takes place.
Birds have negative pressure breathing, but it differs from that of mammals and i more efficient because of what
The maximum PO2 is significantly higher in bird lungs. Bird respiratory system does not mix exhaled air with inhaled air.
How are apes and humans related?
Humans and apes represent divergent lines of evolution from a common ancestor.
What aids mammals in diving?
During a dive, the heart rate slows, and all major blood vessels are constricted except those critical to survival under water. Metabolic rate slows, and tissues switch to glycolytic metabolism.
What probably accounts for the switch to DNA-based genetic systems during the evolution of life on Earth?
DNA is chemically more stable and replicates with fewer errors (mutations) than RNA.
Carnivorous adaptations of plants mainly compensate for soil that has a relatively low content of
What type of plants would not yet have been evolved in the forests that became coal deposits?
What makes the bird's respiratory system more efficient?
Bird respiratory system does not mix exhaled air with inhaled air.
Air rushes into the lungs of humans during inhalation because
The rib muscles and diaphragm contract, increasing the lung volume
What organisms are endothermic homeotherms?
Most birds and mammals. Some large fishes and tuna come very close. (Ectotherm and homeotherms)
Homeotherm = maintain constant body temperature