The RNA world hypothesis states that the earlier life-forms had relied only on RNA (Ribonucleic Acid) for the purpose of catalyzing the chemical reactions, and storing the genetic information. This hypothesis was proposed by Leslie Orgel, Carl Woese, and Francis Crick.
This hypothesis states that long before the living forms evolved to use DNA as the genetic storage material, the RNA molecules served the purpose of both storing the genetic information and carrying out catalysis, but because of its instability, DNA evolved.
Hence, the answer is RNA world hypothesis.
Answer: The phagocyte’s ability to destroy the ingested pathogen is compromised and it will become inactive.
Explanation:
There are different hydrolytic enzymes. Lysozyme attacks cell walls of gram positive bacteria. Elastase is a protease. Collagenase attacks collagen, produced by some bacteria. Plasminogen activator is also a protease.
Loss of function of any one of these enzymes will reduce or prevent the breakdown of bacteria in the phagosome (vacuole) so that the phagocyte is inactivated.
Answer:
The correct answer would be a) circulatory system.
A stroke is primarily caused due to reduced or interrupted supply of blood to the brain.
The blood supply is usually reduced as a result of blockage or bursting of an artery carrying blood to the brain.
Consequently, the brain cells experience a lack of oxygen and nutrients due to which they begin to die.
Thus, stroke is initially caused by damage to the circulatory system.
Answer:
d
Explanation:
reservoirs are places were water are held for a lond period of time. Do a lake or ocean is a place where water is held for a long period of time.
Answer:
I only know 2 of the main ones.
1. Moving
2. Eating
Explanation:
If I figure out the other 2 I will let u know.
