Answer:
External factors include physical and chemical signals. Growth factors are proteins that stimulate cell division. – Most mammal cells form a single layer in a culture dish and stop dividing once they touch other cells.
Explanation:
From Google
Answer: I think it id b But im not positive
Well the red blood cells ( erythrocytes) contain the oxygen carrying pigment known as haemoglobin. Hence RBCs carry oxygen to every cell ion the body.
The white blood cells ( leukocytes) form the cell mediated defence system of the body, they kill microbes and foreign particles either by phagocytosis or lysozymic reactions.
The platelets (thrombocytes) help in the blood clotting process.
This is my comparism of tne blood components.
Please mark me as brainliest.
B. Catalysts are not changed during a chemical reaction.
