Answer:
Explanation:what do you mean?
Answer: RNA polymerase II hope this helps if not comment back and I’ll reply
Answer:
Golgi bodies, endoplasmic reticulum and lysosomes.
Explanation:
Many vesicles are formed in the Golgi bodies and the endoplasmic reticulum, that is responsible for the transportation of materials from one part of the cell to another. Endoplasmic reticulum is the organelle that launches the toxin-loaded vesicles or in other words it is responsible for detoxification i. e. removal of toxic substances from the cell. Lysosomes is the organelle that act against the microorganisms such as bacteria , virus etc.
The correct answer is a - Lipid
Lipids are not considered as macromolecules because unlike proteins, carbohydrates and nucleic acids which polymers, lipids are composed of a single unit made up a glycerol backbone to which two or three fatty acids are linked.
Lipids are not polymers made up of individual subunits called monomers. They contain only one molecule and are not macromolecuels.
Examples of lipids include waxes, steroids, phospholipids and detergents. Lipids are generally hydrophobic and insoluble in water.
Answer:
1. Stabilizing Selection
2. Directional Selection
3. Disruptive Selection
Explanation:
Stabilizing Selection
This type of natural selection occurs when there are selective pressures working against two extremes of a trait and therefore the intermediate or “middle” trait is selected for. If we look at a distribution of traits in the population, it is noticeable that a standard distribution is followed:
Example: For a plant, the plants that are very tall are exposed to more wind and are at risk of being blown over. The plants that are very short fail to get enough sunlight to prosper. Therefore, the plants that are a middle height between the two get both enough sunlight and protection from the wind.
Directional Selection
This type of natural selection occurs when selective pressures are working in favour of one extreme of a trait. Therefore when looking at a distribution of traits in a population, a graph tends to lean more to one side:
Example: Giraffes with the longest necks are able to reach more leaves to each. Selective pressures will work in the advantage of the longer neck giraffes and therefore the distribution of the trait within the population will shift towards the longer neck trait.
Disruptive Selection
This type of natural selection occurs when selective pressures are working in favour of the two extremes and against the intermediate trait. This type of selection is not as common. When looking at a trait distribution, there are two higher peaks on both ends with a minimum in the middle as such:
Example: An area that has black, white and grey bunnies contains both black and white rocks. Both the traits for white and black will be favored by natural selection since they both prove useful for camouflage. The intermediate trait of grey does not prove as useful and therefore selective pressures act against the trait.
