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
Answer:
This question lacks options, they are:
a)Cold forest
b)Tropical forest
c)Temperate forest
d)Cloud forest
e)Alpine forest
The answer is B. Tropical forest
Explanation:
Tropical forest is one of the forests found in nature. The tropical forest receives the best environmental conditions in terms of vegetation growth. Hence, it is said to contain the most diverse organisms in nature. This means that tropical forests holds more species of terrestrial organisms than any other forest or biome.
Therefore, tropical forests are believed to contain 50% of the Earth's terrestrial plants and animal species due to their biodiversity richness.