It’s A an generation that’s the only one that makes sense because evolution is a change over time too
Stem cells arise from the inner mass of the cell
Signalling factors trigger differentiation in stem cells
Genes that lead to the production of undifferentiated blood cells are activated
Signalling factors cause undifferentiated blood cells to produce red blood cells
Explanation:
Red blood cells are formed in the bone marrow. The precursor to the RBC is stem cell which is undifferentiated and pluripotent. The stem cell gets differentiated to form immature RBCs. Immature RBC then gets divided and becomes mature. Stem cell giving rise to RBC is called Haemoctytoblast. The process of erythropoiesis takes 2 days to form new red blood cells
The correct answer is B cells.
<span>Humoral immunity is a type of immunity which is
mediated by antibodies (immunoglobulins IgA, IgB, and IgM) in extracellular
fluids secreted by B cells. B cells recognize antigens or pathogens that are
circulating in the lymph or blood and have a role to neutralize it or eliminate
it.</span>
Answer:
Protein
Explanation:
Melanin is a protein that affects the color of our hair, skin, or animals fur.
I hope it helps! Have a great day!
Pan~
The peripheral nervous system are the nerve cells outside of the the brain and spinal cord.
It connects the central nervous system to sense organs, internal organs, muscles, glands, and blood vessels
