Answer:
A) They form covelant bonds
Explanation:
covelant bonding occurs when pairs of electrons are shared by atoms.
The skin is composed of thin membranous tissue that is quite permeable to water and contains a large network of blood vessels. The thin membranous skin is allows the respiratory gases to readily diffuse directly down their gradients between the blood vessels and the surroundings. When the frog is out of the water, mucus glands in the skin keep the frog moist, which helps absorb dissolved oxygen from the air.
A frog may also breathe much like a human, by taking air in through their nostrils and down into their lungs. The mechanism of taking air into the lungs is however sligthly different than in humans. Frogs do not have ribs nor a diaphragm, which in humans helps serve in expand the chest and thereby decreasing the pressure in the lungs allowing outside air to flow in.
In order to draw air into its mouth the frog lowers the floor of its mouth, which causes the throat to expand. Then the nostrils open allowing air to enter the enlarged mouth. The nostrils then close and the air in the mouth is forced into the lungs by contraction of the floor of the mouth. To elimate the carbon dioxide in the lungs the floor of the mouth moves down, drawing the air out of the lungs and into the mouth. Finally the nostrils are opened and the floor of the mouth moved up pushing the air out of the nostrils.
Frogs also have a respiratory surface on the lining of their mouth on which gas exchange takes place readily. While at rest, this process is their predominate form of breathing, only fills the lungs occasionally. This is because the lungs, which only adults have, are poorly developed.
Im pretty sure that if we got all of our energy from the sun then there would be no energy at night so no
Answer:
a. repressor
b. regulator
c. operator
Explanation:
All constituent genes of an operon are transcribed in a coordinated manner, such as polycistronic mRNA, that is, multigenic, which is sequentially translated into proteins by ribosomes. The initiation of transcription can be regulated positively or negatively. The genes under negative control are constantly expressed unless they are "disconnected" by a repressor protein that will prevent gene expression by binding to a specific DNA sequence called operator, preventing RNA polymerase from initiating transcription in the promoter.
Those genes whose expression is under positive control will not be transcribed unless an activating protein is present which binds to a specific DNA sequence and helps RNA polymerase in the initial steps of transcription.
<span>Answer:
Stacks and queues are special cases of the idea of a collection. ... length of the array items[] so that it is sufficiently large to hold all of the items and but not so large as to waste an excessive amount of space.</span>
