Answer:
Brainliest please
Explanation:
A confirmation test refers to a lab procedure conducted after an initial screen of a submitted sample (commonly urine, hair, blood, breath, or oral fluids) indicates positive results of drug metabolites in the system.
White fur with purple Speckles sometimes I
Answer:
d. Earthworms
Explanation:
Think about it: have you ever actually seen a prion, virus, or bacterium? No, because they can't be seen with the naked eye. Microorganism means that it's too small (hence the prefix micro-) to see.
- Prions are little misfolded proteins. Viruses are nonliving things made up of a protein and nucleic acid. Bacteria are little prokaryotic microorganisms.
They had to adapt to the heat and to learn to survive long periods without water
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.
