19. The atomic number indicates how many neutrons there are, and the atomic mass tells us how many protons and neutrons are present within the nucleus of an atom.
<span>the portion of an antigen that binds covalently to an antibody</span>
So, I decided to take another whack at this, specifically number 3, and at first I didn't really try to answer 'cause I have no clue what the word dueterostome means, but I do know that, for the other two criteria, A, arthropods is the only one that fits both.
also, on 6, it is b, because I remembered what an anther is and it has nothing to do with the eggs (it's the testes, pretty much)
and if I had to guess at 8, I would say it is d because all the others are characteristics of sexual reproduction. (I'm not sure of this, though, because I'm not sure where this defines the line for mitosis, both go through it, but at different points in the process, so I assume it isn't that one.)
Answer:
Peristalsis is the involuntary movement of the muscles that move food through the digestive system.
Explanation:
- Peristalsis is a reflex response.
- It is initiated when the gut wall is stretched by the contents of the lumen.
- Peristalsis occurs in all parts of the gastrointestinal tract from esophagus to the rectum.
- It actually refers to the ringlike contraction of the circular smooth muscle that move progressively forward pushing the bolus.
- It involves coordinated contraction and relaxation above and below the food bolus so that the bolus is pushed forward instead of being pushed back.
Garden will have higher oxygen; it is because their would be more lichen due to more greenry & less pollution;
