C. The number of covalent bonds is equal to the number of unpaired valence electrons. For example, nitrogen and phosphorous both have 3 unpaired valence electrons thus forming 3 covalent bonds.
For nine month because it have to be strong
<h2>The given statement is true</h2>
Explanation:
Iron absorption occurs in the duodenum and upper jejunum of small intestine
- At physiological pH ferrous iron is rapidly oxidized to the insoluble ferric form
- Gastric acid lowers the pH in the duodenum which enhances the solubility and uptake of ferric iron
- Once iron gets inside the enterocyte it can be stored as ferritin;Ferritin is a hollow spherical protein which helps in storage and regulation of iron levels within the body
- Ferritin molecule have ferroxidase activity which helps in the mobility of Fe2+ out of the enterocyte by ferroportin
- Transferrin is the major iron transport protein which transports iron through blood
- Fe3+ binds to transferrin so Fe2+ transported through ferroportin must be oxidized to Fe3+
- Fe2+ needs to be oxidized first so that it can be transported through ferroportin
- Once iron gets inside the cell it can be used for various cellular processes
Answer:
The S phase of a cell cycle occurs during interphase, before mitosis or meiosis, and is responsible for the synthesis or replication of DNA. In this way, the genetic material of a cell is doubled before it enters mitosis or meiosis, allowing there to be enough DNA to be split into daughter cells
<span>homeostasis is the answer </span>
