Answer:
Option-C
Explanation:
Scientists found a fossil of a fish with four limbs or legs. The fossil was estimated to be around 375 million years old.
The fossil showed the fins and scales of a fish but they also possess the bones of proto-wrist, shoulders and the elbow.
The presence of these bones can be a clue that the fish evolved the limbs to walk on the land and will later evolve into animals belonging to amphibians, reptiles and mammals. Therefore, the Tiktaalik is considered the missing link of how life evolved from water to land.
Thus, Option-C is correct.
Answer:
option C. permissive stimuli
Explanation:
The three major kinds of stimulus that triggers the endocrine glands to synthesize and release hormones are humoral stimuli, hormonal stimuli and neural stimuli. The humoral stimulus regulates the release of hormones with the changes in the concentration of extracellular fluids. For example, the increase of glucose concentration in blood causes pancreas to release hormone insulin.
The hormonal stimuli allows secretion of hormone only with the secretion of any other hormone. The hypothalamus gland secretions allows the anterior pituitary gland to secrete hormones. The release of thyroid hormone is an example of hormonal stimuli.
The neural stimuli allows the production of hormones directly from the glands. The production of epinephrine and norepinephrine hormones are the example of neural stimuli. Thus, option C is correct.
Organelles are usually found in eukaryotic cells.
