In biological systems, the chemical reactions concerning glucose and ATP as a product are vital for cellular respiration and photosynthesis. Shortcuts reduce the activation energy, which increases the net "gain" of products. I would go with the last one.
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.
Answer: anthropochory (human dispersal)
Explanation:
Assuming that the bird pollinators were significantly diminished, human dispersal will be a useful means of dispersal. Currently, in the tropics, Jatropha is intentionally planted by individuals for oil production.
Answer:
Ribonucleotides (RNA) and deoxyribonucleotides (DNA). See more details below, please.
Explanation:
Ribonucleotides are the nucleotides of the RNA (they have pentose, ribose and nitrogenous base, except for Thymine; they contain uracil). Deoxyribonucleotides are the nucleotides of DNA (they have pentose, deoxyribose and nitrogenous base, they have Thymine).
Answer: Autocrine signal, paracrine signal and endocrine signal.
Explanation:
Testosterone is an example of hormone which shows its effect on different locations of the cells.
The autocrine signal can be defined as the siganals which shows its effect on the cell from where it is being produced. This means a cell targets itself.
Then comes the paracrine signals in which signals acts locally on the cells nearby it. The cells close together to the cells producing chemical signals is being affected.
The endocrine signals can be defined as the effect of the hormone on the distant cells. The signals is produced by the cells somewhere else but is carried through the bloodstream to the distant cells.
All of the three effects is being shown by testosterone autocrine, endocrine and paracrine.
