Answer:
The definition of a pure line is a result of inbreeding where animals or plants have certain characteristics that are the same through generations. An example of a pure line is the result of inbreeding of a certain flower to help it fight off diseases.
What do you mean but if you mean what I think you mean then you take half of the tadpoles
Arteries are blood vessels responsible for carrying oxygen-rich blood away from the heart to the body. Veins are blood vessels that carry blood low in oxygen from the body back to the heart for reoxygenation. Arteries and veins are two of the body's main type of blood vessels.
Answer: papillary muscle
Chordae tendinae is a connective tissue that used to prevent the heart valve to be flapped away. It like a string that connected into the valve and makes it look like a kite. Papillary muscle is the part that anchoring it to the heart wall.
The answer should be the refractory period
