What was the most important adaptation of the reptiles and birds to life on land?
A. the shelled egg
B. the impermeable egg
C. the amniotic egg
D. the external egg
Answer: C
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Which of the following is true of both neurotransmitters and hormones?
A. They are both involved in paracrine signaling. B. They both interact with receptors inside or on the surface of target cells. C. They are both produced in glands. D. They both travel through the bloodstream to target cells. E. They both influence the activity of multiple organs simultaneously.
The physiologist J. Soum surgically sealed off an air sac of a pigeon and injected carbon monoxide into it. What did he observe and conclude from this experiment?
A. The bird died demonstrating the toxicity of this gas. B. The bird was fine, demonstrating this gas is not actually toxic. C. The bird died, indicating diffusion of gases across the air sac into the blood. D. The bird showed no ill effects, indicating diffusion of gases from the air sac into the blood. E. The bird showed no ill effects, indicating gases do not diffuse from the air sac into the blood.
What is a substance required by all organisms for survival but something that they cannot make on their own?
a. Nutrient b. Sunlight c. Energy d. Carbohydrate e. Oxygen
Since skin is made up of several types of tissues and has a number of different functions, it is best classified as an organ
Indicate whether the statement is true or false