Answer: A natural killer cell (NK) is a type of lymphocyte that has an activating and inhibitory receptors extending from its plasma membrane
Explanation: A natural killer cell (Nk) is a type of lymphocyte (a white blood cell) that has an AC and inhibitory receptors. It plays a major role in host rejection of both tumours and virally infected cells. It contains specifical protein such as perforin and granules.
Answer:
Option-B
Explanation:
Color deficiency is a condition caused when the person is not able to distinguish the different colors. Since the person is not able to distinguish different color, therefore, the chromo-receptors which are affected are the cone cells located in the retina which allows us to see different wavelengths.
1. Total color blindness is not a rare disease in animals.
2. Total color blindness in which a person is not able to see any color occurs when all types of cone cells become malfunction or completely absent.
3. The red-green color blindness is more common than the blue-yellow color blindness.
4. The mother is usually not affected as she is the carrier of the gene responsible for the color blindness.
Since all options except Option-2 are incorrect therefore option-2 is the correct answer.
Centrioles are organelles that are found only in animal cells and they produce D) flagellum and centrosomes.
Centrosomes help organize the microtubules present in the animal cell during cell division and also regulate the cell cycle.
Furthermore, the flagellum produced by centrioles in sperm cells help the cell move towards the egg and cause fertilization.
Answer: A Civil Engineer benefits from the knowledge of physiology because it helps to effectively design buildings to fit human beings adequately. That is, the height of a doorway must effectively take most people.
Explanation: This is when we talk about Ergonomics, that is the environment must effectively fit the user.
Answer:
This question describes a PROTEIN
Explanation:
Proteins are one of the four biological molecules in living systems. It is a biological polymer composed of monomeric units called amino acids, which are chemically joined together by peptide bonds.
An amino acid structurally consists of a central carbon atom bonded to an hydrogen atom, carboxylic acid group (-COOH), an amine group (-NH2) and a R side chain, which distinguishes one amino acid from another. Since all amino acids have a nitrogen-containing amine group, all proteins also contains nitrogen in their structure. Hence, a protein consist of an hydrocarbon (CHO) with a nitrogen atom.
