Answer:
The correct answer would be the virus envelope.
Viral envelope is a protective covering present around the capsid proteins in some viruses.
It is usually derived from the cell membrane of the host and thus it is composed of lipid and viral proteins.
It provides stability to the viral particle, helps in protecting the viral genome, and aids in the fusion of the virus with the membrane of the host.
Examples of viruses in which envelope is present: herpesviruses, poxviruses, flavivirus, hepatitis D et cetera.
Examples of viruses in which envelope is absent: adenoviridae
, papillomaviridae
, picornaviridae
, caliciviridae et cetera.
Answer:
A- Substrate
B- Enzyme
C- Enzyme-Substrate Complex
D- Enzyme
E- Products
Answer: C. Homologous chromosomes are separated in meiosis but not in mitosis.
Explanation: There are two main types of division that take place in eukaryotic cells, mitosis, and meiosis. Mitosis is the type of division that is used for growth, repair, and replacement of tissues. Therefore it is not necessary that the cells have different chromosome numbers or are varied genetically in the daughter cells in the case of mitosis.
Meiosis is the division that takes place to form the gametes for sexual reproduction. It is important in the first stages of meiosis I, to introduce variation and to halve the chromosome number.
Chromosomes numbers are halved (from 46 to 23) during meiosis I because the gametes (sperm and egg) come together and fuse during fertilization to form a zygote. When this fusion occurs (23 from the zygote and 23 from the egg), the chromosome number needs to be returned to that of the parent cell (46).
<h2>
Genetic variation is introduced during synapsis which only occurs in meiosis, not mitosis. Homologs exchange genetic information during crossing over of synapsis. Entire chromosomes also separate during meiosis I.
</h2>
At the end of meiosis, four genetically unique cells are produced with half the number of chromosomes as the parent cell (23 cromosomes) . After the process of mitosis is completed, two cells genetically identical to each pther are produced and have the same number of chromosomes as the parent cell (46 cromosomes).
Genetic variation is actually important because of changing environmental conditions.
Proteins, Ribonucleic acid is another kind of organic molecule that also acts as a catalyst for chemical reactions. Asides acting a catalyst for chemical reactions, proteins have a wide variety of functions that they perform in in living cells.
