The answer to this question would be: increased food height
Giraffe becomes tall because its food height is increased. In this case, the environmental pressure on Giraffe would be the increased height of the food.
The taller giraffe has access to higher food. Then, the giraffe with the higher chance of survival in this scenario would be the giraffe with a taller height.
The correct answer is: prevent reception of a signal in a receiving neuron
Neurotransmitters are signal molecules or chemical messengers which transmit signals across a chemical synapse. Neurotransmitters send the signal, from one neuron (nerve cell) to another neuron, from neuron to muscle cell (motor plate), or from neuron to gland cell.
Drugs that bind to neurotransmitter’s receptor can have two effects on its action:
• Antagonists-they bind to receptor and thus prevent a neurotransmitter from binding to it
• Agonists-they bind to receptor and mimic the normal neurotransmitter (have the same effect as neurotransmitter).
The correct answer is option C. Endocrine glands secrete hormones into the bloodstream because endocrine glands are ductless and the exocrine glands have ducts so they secrete their hormones into the ducts.