2 ) Determine which of the following is the best evidence that thermoregulation in an endothermic animal is taking place?
A) Lung tidal volume (the volume of one inhalation and exhalation) is increased.
B)Cardiac output is decreased.
C)Urine output is increased.
D)The tunica media smooth muscle cells of arterioles in the skin are relaxed.
13) Why does the plant Arabidopsis have 5 different genes that code for 5 different forms of phytochrome?
A.They mediate different types of responses to red and far-red light.
B.Several of them sense red light and the others sense far-red light.
C.All 5 phytochrome types absorb different types of light, maximizing sensitivity of plant to it.
D.Some of the phytochrome types do not function in light absorption but regulate other processes.
14) When a protein hormone binds to a receptor protein located in a cell%u2019s plasma membrane the cell often does something in response to the hormone. How does the signal get into the cell%u2019s cytoplasm?
1.The receptor protein changes shape and in its new shape can interact withproteins inside the cell.
2.The hormone diffuses across the cell membrane and activates enzymes inside the cell.
3.The hormone binds to the receptor and causes the receptor to enter the cell, stimulating enzymes inside.
4.The protein hormone is degraded to amino acids by digestive enzymes and the amino acids enter the cell through channels to increase the cell%u2018s metabolic rate.
15) Gravitropism in plant roots appears to be mediated by:
1.The lack of red light in the soil.
2.Starch granules that move down a gravitational field.
3.Signaling from root cap cells.
4.Increased division of root apical meristem cells on the side nearest the surface of the soil.
20) Production of the flowering hormone florigen can be stimulated in one plant and then passed to other plants only if:
1.The plants are all close to each other so the hormone can diffuse through the air from one to another.
2.The vascular systems of all the plants are connected to each other.
3.Red light illumination is followed by far-red illumination of at least one of the plants.
4.The plants%u2019 roots touch the roots of other plants.