Permian-Triassic extinction
Answer:12
Explanation:its the only one under 18
If the pH/temperature fluctuates, the enzyme conditions would no longer be favorable, meaning the enzyme would no longer be able to perform its assigned function. If the conditions become too unfavorable, the enzyme would change shape (denature).
Answer: Receptor protein.
Explanation:
The receptor protein on the cell surface would enable a cell to respond to glucagon. The glucagon binds to the GPCR on the liver and muscle cells and is known as glucagon receptor.
This receptor then stimulates cells to release glucose into the blood stream. Another hormones involved during this process is glucagon like peptide 1.
It works by binding to another GPCR which is GLP-1 receptor found on the pancreatic cells.
<h2>a,d,b,c is the correct order</h2>
Explanation:
Before oxygen is picked up in the lungs by hemoglobin, it first diffuses through (a) alveolar cells,d) capillary walls (b) blood plasma, (c) red blood cell plasma membranes
- Although oxygen dissolves in blood, only a small amount of oxygen is transported this way,1.5 percent of oxygen in the blood is dissolved directly into the blood itself and most oxygen—98.5 percent—is bound to a protein called hemoglobin and carried to the tissues
- Hemoglobin (Hb) is a protein molecule found in red blood cells (erythrocytes) made of four subunits: two alpha subunits and two beta subunits
- Each subunit surrounds a central heme group that contains iron and binds one oxygen molecule, allowing each hemoglobin molecule to bind four oxygen molecules
- Molecules with more oxygen bound to the heme groups are brighter red because of which oxygenated arterial blood where the Hb is carrying four oxygen molecules is bright red, while venous blood that is deoxygenated is darker red
- At the same time, carbon dioxide that is dissolved in the blood comes out of the capillaries back into the air sacs, ready to be breathed out
- Oxygenated blood travels from the lungs through the pulmonary veins and into the left side of the heart, which pumps the blood to the rest of the body
- Oxygen-deficient, carbon dioxide-rich blood returns to the right side of the heart through two large veins, the superior vena cava and the inferior vena cava
- Then the blood is pumped through the pulmonary artery to the lungs, where it picks up oxygen and releases carbon dioxide
