Answer:
Option A, Hormones are controlled by a feedback loop; information about a system is sent back to the controller of the system to improve its function.
Explanation:
Negative feedback loop controls the hormone production and release. This is done by eliciting the release of substances till a certain level after which the stop signal is activated thereby preventing further release. By this method, concentration of hormones in blood is maintained within the narrow range.
For example – Thyroid hormones is released when the anterior pituitary signals the thyroid. This continues till the hormones in the blood reach the threshold level. Once the threshold level is reached, hypothalamus receives a feedback and then signals anterior pituitary to inhibit further signaling to the thyroid
Hence, option A is correct
D.
variable-ratio schedule of reinforcement.
Answer:
Low Enzyme Production is the reason for no breaking down of food.
Explanation:
If the digestion of food did not occur so it means that there is low enzyme production because enzymes are responsible for the breaking down of food substances into simpler ones in order to absorb by the cells for the generation of energy in the form of ATP. So we can conclude that low enzyme production is the only reason for the stopping of breaking down or digestion of food.
All the options are correct.
1. New ways to preserve and transport blood for blood transfusions were discovered.
2. Blood transfusion safety was improved.
3. Scientists discovered that elements of blood could be separated by centrifuge.
4. Scientists discovered that plasma could be preserved by freezing.
Karl Landsteiner
Karl Landsteiner was the man who discovered some of the human blood types in 1900 and 1901 at the University of Vienna.
Answer:
Cellulose is held by beta 1,4-glycosidic bonds making it linear while Glycogen is held by an alpha 1,4-glycosidic bond making it highly branched.
Explanation:
Cellulose and Glycogen are both carbohydrate polysaccharides formed from glucose monomers. According to the question, cellulose is a tough, fibrous, and insoluble (in water) polymer found to play a structural role in plants' cell wall while Glycogen is another polymer obtained from muscle or liver and disperses readily in hot water to make a turbid solution.
Although these two polysaccharides (cellulose and glycogen) are linked by (1, 4)-glycosidic bonds but the glucose monomers in CELLULOSE are linked by a beta 1,4-glycosidic, hence, making it a straight or linear polymer
GLYCOGEN, on the other hand, is linked by an alpha 1,4-glycosidic bond making it an highly branched polymer. This structure is responsible for the different physical properties of the two molecules.