<u>Answer</u>:
The organic chemicals that helps cell membranes to conserve the internal fluids are phospholipids.
<u>Explanation</u>:
Phospholipids are used to form plasma membrane of the cell. Plasma membrane surrounds the cell contents like various cell organelles, nucleus, ribosomes and proteins. A phospholipid molecules is made up if a polar head containing a phosphate group and the two non-polar tails made of long chains of hydrocarbon of fatty acids.
The another name for plasma membrane is phospholipid bilayer. The polar head is hydrophilic that interactes with polar environment while facing outside the bilayer while the non-polar tail is hydrophobic in nature which makes the internal hydrophobic region of cell membrane which faces inside the bilayer.
Carbon is the atom, which is necessarily find in the living organism.
All the living organisms are made up of biomolecules. All the biomolecules are organic compounds. The substance cannot be consider as living, if it lacks nucleic acids. There are two types of nucleic acids DNA (deoxyribonucleic acid) and RNA (ribonucleic acid), both have a structure made up of carbon rings and chains.
Other than nucleic acids, proteins, enzymes, hormones etc are also made up of carbon. So, all the living cells, or dead remain of organism must have carbon atom.
Hence, the correct answer is option D. carbon.
Answer:
Mutation, Gene flow/Migration/Immigration of gene and Recombination
Explanation:
For any species there are majorly three sources of genetic variations –
a) Mutation – This leads to change in the genetic code with in the DNA of an organism. Sometimes mutation does not produce any effect on the organism. Mutation can produce both positive and negative impact. Its effect is observed in long run as its rate is slow.
b) Recombination – When an organism undergoes sex, his/her genes recombine with the genes of mating partner. The rate of recombination is faster than the rate of mutation
c) Gene flow /Migration/Immigration of gene – In this gene travel from one set of population to the other. The frequency of gene in the mixed population lies between the original population gene frequency and the migrated or donor population gene frequency
Vacuole is the answer.
Wilting is the loss of rigidity of non woody parts of plants and occurs when turgor pressure falls.
The vacuole controls turgor pressure. Turgor pressure dictates the rigidity of the cell and is associated with the difference between the osmotic pressure inside and outside the cell.
When a plant receives adequate amounts of water, the central vacuoles of its cells swell as the liquid collects within them creating a high level of turgor pressure which helps maintain the structural integrity of the plant along with the support of the cell wall.
In the absence of enough water , central vacuoles shrink and turgor pressure is reduced compromising the plant's rigidity so that wilting takes place.
The given blank can be filled with the production of endorphins.
The endorphins are the hormones, which are responsible for the activation of the opiate receptors in the body. They are the natural pain killers. The activation of the opiate receptors causes the analgesic effects on the body.
These endorphins are secreted in the brain and the nervous system. The effect of the endorphins is similar to that of the morphine.
