Answer:
Because fertilization in diploid gametes would double the number of chromosomes in the zygote. If chromosome numbers are disturbed the organism develops abnormalities or even die.
Answer: d. none of the other answers
Explanation:
Enzymes that turn chemical energy into mechanical work are molecular motors.
There are three main components of cytoskeleton including microtubules, actin filaments and Intermediate filaments. Only actin filaments and microtubules carry the motor-driven transport on the cytoskeleton.
The most important feature of intermediate filaments is to provide the plasma membrane with mechanical support where it comes into contact with the extracellular matrix and other cells.
Unlike microtubules and microfilament , intermediate filaments are not involved in motility of the cells, hence do not associat with molecular motors.
Hence, the correct option is d.
Answer:
to adapt to the environment and maintain homeostasis
Answer:
The ability of caffeine to inhibit adenosine receptors, plays a very important role in heightened alertness and sleeplessness.
Explanation:
"<em><u>Caffeine</u></em>" (<em>1,3,7-trimethylxanthine</em>) is an alkaloid obtained from plants. It has a chemical formula of C8H10N4O2.
Caffeine is generally <em>hydrophillic</em> but sufficiently <em>lipophilic</em> to pass through all biological membranes and readily cross the blood-brain barrier.
Therefore can bind with the adenosine receptors. Due to the blocking of adenosine inhibitory effects through its receptors held by paraxanthine and caffeine, it indirectly affects the release of <u>norepinephrine, dopamine, acetylcholine, serotonin, glutamate</u> e.t.c.
The release of the above-mentioned hormones have a great impact on the heightened alertness of the body, especially <em>dopamine</em> and <em>serotonin</em>.
