The correct answer is A - chlorophyll.
It is a green pigment found in the chloroplasts of green plants. Chloroplasts are mostly found in the leaves of green plants and also in some algae.
Plants use chlorophyll to trap light energy from the sun. Without the light energy, plants cannot be able to carry out the process of photosynthesis, which converts water and carbon dioxide into starch that plants use for food.
Photosynthesis also releases oxygen which is vital for animal life.
Answer:
B. often use tube feet to move around in their environment
Explanation:
Tube feet are tiny tubular projections of echinoderms on the underside (oral side). They are a member of the echinoderm water vascular system.
Tubular feet are used for feeding, breathing and shifting. They are arranged around the sides, in grooves. They work by hydraulic pressure. They are used to transfer food in the centre to the oral mouth, and may stick to surfaces. Tube feet allow certain animals to stick and travel slowly to the ocean floor. for example starfish uses tube feet for the above functions.
Hence, the correct option is B.
Growth factors are hormones, proteins, or steroid molecules that regulate many cellular functions. They can stimulate the cell division by giving the signal to the cell to progress in the cell cycle.
<u>Explanation</u>:
Growth factors are naturally produced within the body and travels through the body to bind to their receptors present on their target cells. These growth factors are capable of signalling the cell to divide, proliferate, or heel. Their main aim is to signal or tell other cell when to do and what to do. Due to the binding with the receptors the growth factors activates specific genes.
Answer:
a. adenine and guanine
Explanation:
A purines nucleotide is a combination of the heterocyclic aromatic rings, the imidazole and pyrimidine ring.
<span>The thinnest parts are oceanic crust, while the thicker parts are continental crust.</span><span />
