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.
Answer: The thoracic cavity contains the heart, lungs and many of the main vessels of the circulatory system. It is found anterior to the vertebral cavity.
Explanation:
The thoracic cavity is the second largest hollow space of the body and it is the space limited by the ribs, the vertebral column, and the sternum. It is the upper region of the body starting from the neck and ending where the diaphragm ends. So, it is separated from the abdominal cavity by the diaphragm. It contains 12 ribs, and 7 of them attach directly to the sternum, 3 attach to the sternum via cartilages and 2 do not attach to the sternum at all and are called floating ribs. The cavity contains several organs, such as the lungs, heart, great vessels and esophagus.
The abdominal cavity spaces around the organs are filled with the core muscles that attach to the posterior spine. Besides. the ribs vertically, horizontally and across the abdominal region.
The vertebral cavity is the posterior portion of the dorsal cavity, it contains the spinal cord within the vertebral column, the meninges and the fluid-filled spaces between them. It is formed by the vertebrae through which the spinal cord passes.
<u>The thoracic cavity is anterior to the vertebral cavity, because anterior describes the front or direction toward the front of the body</u>.
Answer:
In acid-fast staining, carbon fuchsin is used as a primary stain which dissolves the mycolic acid present in the cell wall of <em>Mycobacterium smegmatis </em>and penetrates through it which results in staining <em>Mycobacterium</em> red.
Staphylococcus aureus cell wall does not contain mycolic acid so carbon fuchsin does not penetrate its cell wall, therefore, it becomes colorless after destaining with acid alcohol.
After destaining step methylene blue is added to stain non-acid-fast bacteria blue. So if I mistakenly forgot to use methylene blue during the procedure <em>Mycobacterium smegmatis</em> will appear red due to carbon fuchsin present in their cell wall and S<em>taphylococcus aureus</em> will appear colorless because it is destained.
The first things that should be done would be to ensure that you yourself are aware of the hazardous materials that are present, protect yourself, and call for personnel. Hope this helps!
Answer: The correct answer is D) Some energy in each trophic level is used for life processes.
Food chain represents the flow of energy through various living organisms (which lie at different trophic levels) in an ecosystem. The energy flows from one trophic level to the next and it is decreased with subsequent trophic levels.
As per the law of 10% energy transfer, only 10 % of the energy is transferred from one level to the next as the rest of the energy at every trophic level is utilized in various metabolic processes like respiration, digestion, excretion and also liberated as heat in the surrounding.
Due to this, the energy available at any trophic level is less than the previous trophic level.
