Fresh water is any body of water with a low salt concentration. Organisms in fresh water various challenges which includes; Osmotic concentration such that fresh water is permanently dilute and most cells cannot function at this concentration of ions. Varying temperatures, variation in oxygen levels and reproduction and life cycle due to permanence of habitat and physiological difficulty of regulating osmotic concentration in larvae and juveniles.
Answer: A niche is the role an organism plays in the ecosystem.
Explanation: A niche also determines how the organism interacts with other organisms in an ecosystem
the main difference is that bacteria are free-living cells that can live inside or outside a body, while viruses are a non-living collection of molecules that need a host to survive.
Many bacteria help us: living in our gut digesting and helping absorption of our food, fixing nitrogen and decomposing organic materials in soil. Similarly, not all viruses are bad—we now know there are also beneficial viruses present in our gut, skin and blood that can kill undesirable bacteria and more dangerous viruses.
Cholesterol is one of the molecules composing the cell membrane. b) makes the cell membrane fluid at room temperature.
<h3>What is the role of cholesterol in the cell membrane?</h3>
The cell membrane is composed of two lipidic bilayers, cholesterol, proteins, and glucans incrusted in between.
Cholesterol is one type of lipid.
These molecules are incrusted in the membrane between the hydrophobic tails of lipids.
Their proportion on both sides of the membrane is almost the same.
Cholesterol is a significant molecule that contributes to the membrane fluidity, separates phospholipids, and interact with membrane proteins regulating in their activity.
The correct option is b). makes the cell membrane fluid at room temperature.
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