It takes seven seconds for the pupil to adapt once again to dark conditions after getting exposed to headlight glare.
The pupil of the eye refers to the black circle at the midpoint of the iris. The pupil functions mainly to monitor the amount of light getting inside the eyes, to make sure that to much light does not blanch out the visions in extremely bright light conditions, and to capture as much light as possible in dim light conditions.
Answer:
Flowering plants grow plants and use seeds to reproduce, or make more plants like them.
Explanation:
Answer:
True
Explanation:
Some deviations from normal homeostasis activate the positive feedback loops to control the conditions which are otherwise regulated by negative feedback mechanisms.
For example, the blood levels of respiratory gases and H+ ions are regulated by a negative feedback system via chemoreceptors. The increased partial pressure of carbon dioxide gas and lowered pH or lowered partial pressure of oxygen in the blood are sense by central and peripheral chemoreceptors which in turn activate the neurons of the dorsal respiratory group (DRG).
The activated DRG triggers an increased in the rate and depth of the breathing to facilitate the inhalation of more oxygen and exhalation of CO2 to restore the normal levels.
However, hypocapnia inactivates the chemoreceptors and does not allow negative feedback to restore the normal CO2 levels in the blood.
Under such conditions, the positive feedback loop stimulates the DRG neurons more strongly in response to the increased partial pressure of CO2 above the normal levels than when the partial pressure of oxygen falls below the normal level. These dangerously lowered oxygen levels may also cause fainting.
Answer:
This question is incomplete, the options are:
A) Decreased temperature
B) Strong southerly winds
C) Presence of a predator
D) Lack of water
The answer is C
Explanation:
A stimulus is something that provokes a response or reaction in a living organism. It can either be internal or external. An animal can respond to stimulus such as hunger, heat, predator etc.
However, among all the listed stimuli in the options, the PRESENCE OF A PREDATOR is most likely to result in a more rapid heartbeat in an animal. This is because the predator stimulus will require the animal to respond by running in order to survive. Running will increase its metabolic activity and cause its heartbeat to increase.
