D. Observe how coral colonized a sunken ship. Ecologists look at how a whole ecology develops and maintains itself, so in this case, the coral on the sunken ship would be a whole ecology and the person studying it would be an ecologist.
Answer:
B. The available donors and acceptors will induce gene expression of their redox enzymes, thereby allowing their use
Explanation:
Electron transport chain is the important stage of cellular respiration where the electron is donated by certain redox molecules.
The ETC takes place in both the aerobic and anaerobic type of respiration wherein the aerobic respiration, oxygen is used as the electron acceptor whereas in the anaerobic respiration some other molecules like sulfate and nitrate are used.
In anaerobic respiration, the type of electron donors and the donor-acceptor molecules determine the fate of the chain as these molecules act as an inducer of the genes of redox enzymes and the genes for the enzymes are expressed.
Thus, Option-B is correct.
Answer:
a prezygotic barrier
Explanation:
Both wild tigers and lions are said to be reproductively isolated.
Reproductive isolation is defined as the existence of barrier between organisms of different species such that they cannot reproduce.
The mechanisms of reproductive isolation varies. While some act to prevent the formation of zygotes (in case of mating) between organisms of different species, some ensures that the resulting zygotes are invalid.
Reproductive isolation mechanisms that act to prevent fertilization and formation of zygotes are referred to as prezygotic mechanisms while those that ensure that invalid zygotes result (in case of successful fertilization) are referred to post zygotic mechanisms.
<em>The natural differences in the ranges of wild tigers and lions ensure that both animals do not mate with each other, let alone results in zygote. This is a form of pre-zygotic reproductive isolation mechanism.</em>
A white blood cell engulfing foreign materials is more likely to carry out Endocytosis.
Explanation:
- Endocytosis is the process by which a cell takes up a macromolecule into is cytoplasm by forming a vessicle.
- In the question two cases are given, both the cases involve the formation of membrane bound vessicle but in different ways.
- The excretion of hormones involves the movement of molecule outside the cytoplasm. This process is exocytosis.
- The engulfment of an antigen by WBC involves taking up of molecule within the cell so that it can be killed and digested. Thus in this case Endocytosis is more likely to occur..
