As blue whales migrate, they move between areas of high and low sunlight intensity. When they are in areas

Briefly outline the steps involved in glycogen synthesis and breakdown and explain the regulatory mechanism involved in glycogen

Elenna [48]

Answer:

Glycogen is synthesized and degraded by different pathways, which provide greater flexibility for energy production through its degradation or for storage in its synthesis and thus maintain control of both metabolic pathways.

Explanation:

Synthesis and degradation pathways:

1º.- activation of glucose units at UDP-glucose.

UDP-glucose is an activated form of glucose, which is formed in a reaction catalyzed by UDP-glucose, which is formed in a reaction catalyzed by UDP-glucose pyrophosphorylase. This reaction is an example of biosynthetic reactions that are directed by the hydrolysis of pyrophosphate (PPi-2Pi).

Many biosynthetic reactions are directed by the hydrolysis of pyrophosphate, which catalyzes pyrophosphate hydrolase or pyrophosphatase, and is very favorable thermodynamically.

2nd.- polymerization or addition of glucose units to glycogen. Two steps: addition and branching.

UDP-glucose acts as the giver of glucose units for glycogen synthesis. Glucose transfer

from the UDP-glucose to a growing glycogen chain is catalyzed by glycogen synthase.

A branching enzyme [amyl (1,4 -> 1,6) -transglucosidase], moves a chain of about seven glucose residues, to form

bonds (α1-> 6) at the branching points.

To start glycogen synthesis, glycogen synthase is only effective when it is linked to glycogenin. Glycogenin is

an oligosaccharide carrier protein formed by glucose units with linkages (α1-> 4).

6 0

3 years ago

Is blood clotting an example of a positive or negative feedback mechanism? Explain your answer based on the description of the m

serg [7]

Answer:

Blood clothing is an example of positive feedback.

This type of feedback mechanism is useful to the body because it multiplies the factor that intervenes in clotting accelerating the process.

If a toxin affects the molecules that signal for platelets the feedback will not be effective enough to produce clotting and the body will keep bleeding.

Explanation:

Blood clotting is an example of positive feedback due to the fact that when the vascular endothelium is damaged platelets will go to this area and activate themselves once they are in contact with the collagen fibers of the damaged structure. When the platelets are activated they will release the contents that is stored in their granules. One of the contents is a Gq-linked protein receptor cascade, that will increase the concentration of calcium in the platelets. Calcium activates protein kinase C, which, in turn, activates phospholipase A2 (PLA2). PLA2 will modifies an integrin membrane increasing its affinity to bind fibrinogen. The activated platelets change their shape , and the fibrinogen cross-links with the integrin membrane aiding in the aggregation of adjacent platelets. After this the coagulation cascade takes place. there are two pathways the extrinsic and the extrinsic one.

The extrinsic pathway will be activated due to tissular factor released by the platelets and the intrinsic pathway will be activated due to endothelial collagen. The final product of both pathways is factor x.

Factor x will transform prothrombin into thrombin will activate the conversion of fibrinogen into fibrin. Thrombin will form a net of fibrin that will the clot.

A cascade reaction is useful because every component of the cascade are related making a quick reaction once that one of then is activated and can activate other or more factors.

If a toxin affects the molecules that signals for platelets, platelets will not go to the damaged area and in consequence there will not be thrombin and fibrin to form the clot together with platelets.

7 0

3 years ago

What genotype would puppies have if two labradoodles were bred together?

amid [387]

Answer:

The answer is heterozygous

7 0

3 years ago

Read 2 more answers

Researchers create a recombinant DNA molecule in which the coding sequence for GFP is inserted downstream of the enhancer/promot

Stolb23 [73]

Answer:

-Reporter gene.

Explanation:

A reporter gene can be defined as a gene, which is used as an indicator to check uptake or expression of gene by a cell or organism. It is attached to a regulatory sequence of a different gene of interest in cell culture, bacteria, plants, or animals by the researchers and used to confer its expression in that organism or cell.

Gene for GFP (green fluorescent protein) is an example of reporter gene, due to which cells that express gene of interest emit green color under blue light.

As in given experiment, target gene (gene for rhodopsin) is attached with gene for GFP, it represents an example of reporter gene.

Thus, the correct answer is 'reporter gene.'

5 0

3 years ago

Who are bigger, the red blood cells or the white blood cells?.

nlexa [21]

Answer:

White blood cells ↓

These are donut-shaped cells that are similar to red blood cells, and do have a similar duty, yet are larger.

5 0

2 years ago