Four general conditions necessary for natural selection to occur<span> are: A. More organisms are born than can survive. B. Organisms vary in their characteristics, even within a species. D. Differences in reproduction and survival are due to variation among organisms.</span>
b
Explain why viruses are not considered to be living.
viruses are not considered to be living because they lack cells and cannot reproduce on their own. although viruses contain DNA, they do not have a cell membrane, cytoplasm, ribosomes, or other organelles. they also need to use the cells of living organisms in order to replicate.
The correct option is this: BECAUSE OF A SPINAL REFLEX.
Reflex action refers to the involuntary movement of any part of the body when such a part receive a stimulus. The response to reflect action is always immediate and it occurs without the consent of the affected person. Examples of reflex action is the contraction of the pupils when light shines in one's eyes and the quick withdrawal of one's hands when one touch a hot object.
I believe the correct answer among the choices listed above is option B. A gland secretes enzymes through a duct onto the surface of a body part is a salivary gland. It is under the classification of exocrine glands. Hope this answers the question.
That isn't even possible. Your body is made of them. If you had none then you wouldn't be existing.
