Yes Carbon dioxide is necessary for photosynthesis because Photosynthesis didn't go on because there was no Carbon dioxide in flask X.
The carbon dioxide was absorbed by the sodium hydroxide. In flask Y, the colour of the iodine solution turned blue black. This is because starch was present in the leaf of flask Y. Starch was present because it underwent photosynthesis.
The answer is polygenic inheritance.
Many physical characters (traits) depend on many different factors, each of which is determined by different genes. This is called polygenic inheritance.
For example, the color of the skin in humans. The color of the skin results from the interactions of several factors determined by different pairs of genes:-Certain genes could affect the metabolism of skin melanocytes.-Other genes can determine the distribution of melanin in the thickness of the skin.-Some genes could determine the relative amounts of each of the two possible types of melanin.-Others may affect the production of certain hormones involved in the activity of melanocytes.
Hormones glucagon and insulin are produced in the alpha and beta cells respectively in the Islet of Langerhan in the pancreas. They are involved in the negative feedback system of blood glucose regulation in homeostasis.
GLUCAGON: when there is a low blood glucose concentration, the pancreas detect this and alpha cells produce and release glucagon. Glucagon causes the cells of the body to absorb less glucose from the blood. It also inhibits the process of converting glucose into glycogen (glycogenesis) and cause gluconeogenesis (process of converting amino acids/proteins and lipids/fats into glucose) and glycogenolysis (conversion of glycogen to glucose). Finally, glucagon decreases the rate of respiration so less glucose is required.
INSULIN: when blood glucose is high, insulin is released. Insulin binds with cell surface receptors of cells and activates the enzymes attached to the receptor. The enzymes cause a conformational change in the structural proteins that surround glucose transport protein containing vesicles, causing them to move out of the way so the vesicles migrate up to the cell membrane and glucose transport proteins can fuse with it. Thus, more glucose can be taken in by cells. Insulin also cause glycogenesis (converting glucose into glycogen) and inhibits gluconeogenesis and glycogenolysis.
Basically insulin decreases blood glucose concentration (eg. after eating) and glucagon increases it (eg. skipping breakfast in the morning)
Answer:
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