Divergent. convergent, and transform.
Answer:
c. a high percentage of very long chain saturated fatty acids
Explanation:
Saturated fatty acids do not have double bonds (they are saturated with hydrogens), so their tails are relatively straight. Unsaturated fatty acids, on the other hand, contain one or more double bonds, which often produces an elbow or bend. (You can see an example of an unsaturated bent tail in the phospholipid structure diagram that appears at the beginning of this article.) Saturated and unsaturated phospholipid fatty acid tails behave differently when the temperature drops:
- At colder temperatures, the straight tails of saturated fatty acids can be tightly bound, producing a dense and quite rigid membrane.
- Phospholipids with unsaturated fatty acid tails cannot bind so closely due to the bent structure of their tails. For this reason, an unsaturated phospholipid membrane remains fluid at lower temperatures than a saturated phospholipid membrane.
Most cell membranes contain a mixture of phospholipids, some with two saturated (straight) tails and others with a saturated tail and an unsaturated (folded) tail. <u>Many organisms — fish, for example — can adapt physiologically to cold environments by changing the proportion of unsaturated fatty acids in their membranes, that is, increasing the proportion of saturated long-chain fatty acids.</u>
In addition to phospholipids, animals have an additional component in their membrane that helps them maintain fluidity. Cholesterol, another type of lipid that is embedded between the membrane phospholipids, helps decrease the effects of temperature on fluidity.
Loss of animals is a possible negative result
1. You can have an infinite amount of proteins from only a few amino acids, it would be all in the way they are tied together.
2. Lipids are not considered polymers because the base units of lipid are not considered monomers
3. carbohydrates have a 5-carbon ring.
Lipids have long tails of fatty acids, CH2
Answer:
Increased genetic variation reduces the species chances of being extinct. Conversely, reduced genetic variation in a species increase the chances of the species being extinct.
Explanation:
With increased genetic variation in a species, there is increased phenotypic variation amongst organisms in the species for natural selection to act on with selection pressures exerted upon the species in their environment e.g. predation or diseases. Hence even if a certain genotype express susceptibility to a certain disease, only some organisms will be selected against and there are sufficient organism without this genotype that will be able to survive and ensure the continuity of the species.
Conversely, if all the organisms express the same genotype susceptible to the disease (in extreme cases), upon exposure to the disease (which acts as the selection pressure), all the organisms will die and there will be no surviving organisms for the continuity of the species. Hence with minimal genetic variation, the species is more prone to extinction due to the inability to withstand selection pressures.
This is often a common cause of concern in the conservation of endangered species. Due to the small number of e.g. tigers remaining, most offsprings are produced through inbreeding between family members thus even though the family tree of the species is expanding, there is little genetic variation within the species. Therefore, the chances of extinction of these endangered species is high and thus biologists and conservationists have to monitor the selection pressures exerted upon these species by their environment to reduce the risk of extinction.
