C. <span>eukaryotic cells contain organelles that are enclosed in membranes.</span>
Answer:
They once thought that humans came from monkeys and apes but now they think they come from a ancient ancestor not from the monkey or ape family.
Explanation:
A,B,C and D
A. increase in the number of available neurotransmitters
B. decrease in the number of available neurotransmitters
C. increase in the number of receptors and receptor sites
D. the ability of the synapse to change in strength and function when the pathway is overused or underused
Answer:
Oxygen liberated during photosynthesis comes from the splitting or hydrolysis of water in the green plants. Cornelius van Niel experimentally proved for the first time that the oxygen liberated during photosynthesis comes from water and not from carbon dioxide.
Answer: D
Explanation:
During embryogenesis, hematopoiesis begins in week 3 in the Yolk Sac, in Pander´s Island or Wolff´s Island, commonly known as the "blood islands". These blood islands develop from the umbilical vesicle, allantois, and chorion. In week 5, blood production starts on the fetal liver, and finally, at week 12 it begins in the bone marrow, spleen and, thymus.
