What are 3 modifications to pyruvate in the intermediate phase

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Answer 1
Answer:

Answer:

Simplified diagram of pyruvate oxidation. Pyruvate—three carbons—is converted to acetyl CoA, a two-carbon molecule attached to coenzyme A. A molecule of coenzyme A is a necessary reactant for this reaction, which releases a molecule of carbon dioxide and reduces a NAD+ to NADH.

Simplified diagram of pyruvate oxidation. Pyruvate—three carbons—is converted to acetyl CoA, a two-carbon molecule attached to coenzyme A. A molecule of coenzyme A is a necessary reactant for this reaction, which releases a molecule of carbon dioxide and reduces a NAD+ to NADH.

In eukaryotes, this step takes place in the matrix, the innermost compartment of mitochondria. In prokaryotes, it happens in the cytoplasm. Overall, pyruvate oxidation converts pyruvate—a three-carbon molecule—into acetyl two-carbon molecule attached to Coenzyme A—producing an t, N, A, D, H, end text and releasing one carbon dioxide molecule in the process. Acetyl  C, o, A, end text acts as fuel for the citric acid cycle in the next stage of cellular respiration.

Pyruvate oxidation steps

Pyruvate is produced by glycolysis in the cytoplasm, but pyruvate oxidation takes place in the mitochondrial matrix (in eukaryotes). So, before the chemical reactions can begin, pyruvate must enter the mitochondrion, crossing its inner membrane and arriving at the matrix.

In the matrix, pyruvate is modified in a series of steps:

More detailed diagram of the mechanism of pyruvate oxidation.

1. A carboxyl group is removed from pyruvate and released as carbon dioxide.

2. The two-carbon molecule from the first step is oxidized, and NAD+ accepts the electrons to form NADH.

3. The oxidized two-carbon molecule, an acetyl group, is attached to Coenzyme A to form acetyl CoA.

More detailed diagram of the mechanism of pyruvate oxidation.

A carboxyl group is removed from pyruvate and released as carbon dioxide.

The two-carbon molecule from the first step is oxidized, and NAD+ accepts the electrons to form NADH.

The oxidized two-carbon molecule, an acetyl group, is attached to Coenzyme A to form acetyl CoA.

Image credit: "Oxidation of pyruvate and the citric acid cycle: Figure 1" by OpenStax College, Biology, CC BY 3.0

Step 1. A carboxyl group is snipped off of pyruvate and released as a molecule of carbon dioxide, leaving behind a two-carbon molecule.

Step 2. The two-carbon molecule from step 1 is oxidized, and the electrons lost in the oxidation are picked up 2 \text{NADH}NADHstart text, N, A, D, H, end text are generated from \text{NAD}^+NAD

Step 3. The oxidized two-carbon molecule—an acetyl group, highlighted in green—is attached to Coenzyme A (\text{CoA}CoAstart text, C, o, A, end text), an organic molecule derived from vitamin B5, to form acetyl \text{CoA}CoAstart text, C, o, A, end text. Acetyl \text{CoA}CoAstart text, C, o, A, end text is sometimes called a carrier molecule, and its job here is to carry the acetyl group to the citric acid cycle.

The steps above are carried out by a large enzyme complex called the pyruvate dehydrogenase complex, which consists of three interconnected enzymes and includes over 60 subunits. At a couple of stages, the reaction intermediates actually form covalent bonds to the enzyme complex—or, more specifically, to its cofactors. The pyruvate dehydrogenase complex is an important target for regulation, as it controls the amount of acetyl \text{CoA}CoAstart text, C, o, A, end text fed into the citric acid cycle^{1,2,3}

1,2,3

start superscript, 1, comma, 2, comma, 3, end superscript.

If we consider the two pyruvates that enter from glycolysis (for each glucose molecule), we can summarize pyruvate oxidation as follows:

Two molecules of pyruvate are converted into two molecules of acetyl \text{CoA}CoAstart text, C, o, A, end text.

Two carbons are released as carbon dioxide—out of the six originally present in glucose.

2 \text{NADH}NADHstart text, N, A, D, H, end text are generated from \text{NAD}^+NAD

+

start text, N, A, D, end text, start superscript, plus, end superscript.

Why make acetyl \text{CoA}CoAstart text, C, o, A, end text? Acetyl \text{CoA}CoAstart text, C, o, A, end text serves as fuel for the citric acid cycle in the next stage of cellular respiration. The addition of \text{CoA}CoAstart text, C, o, A, end text helps activate the acetyl group, preparing it to undergo the necessary reactions to enter the citric acid cycle.

Explanation:


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Write an essay on ecosystem productivity​

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A ecosystem productivity is a rate of generation of biomass.’’I know this because it states.”In economy productivity refers to the rate of generation of biomass in an economy.This shows that the economy its usually expressed in units of mass per unit.

An organic methyl molecule attached to part of a DNA strand has been identified as a(n) epigenetic mark. double helix. self-regulating gene. genome.

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Answer:

Epigenetic mark

Explanation:

A methyl group attached to the nitrogenous base of one amino acid on the DNA is known to have effects on the expression and transcripcion of the genes, and this is also called epigenetic modifications. Therefore, an methyl group attached to the DNA is responsible for epigenetic modifications and so is an epigenetic mark.

A virus requires a host cell in order to?

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Infect to reproduce
Hope it helps you

Meiosis allows a plant to produce offspring plants with which characteristic?a high rate of random mutations
traits identical to those of the parent plant
characteristics adaptive to the plant's environment
unique combinations of genetic material

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Answer:

unique combinations of genetic material

Explanation:

Meiosis is one of the two types of cell division in which an organism produces daughter cells that are genetically different from the parent cell. Meiosis is the cell division which the cell uses to produce gametes (daughters cells).

The daughter cells are different genetically in the sense that they contain a different combination of chromosomes, which occurs in a process called CROSSING OVER. Therefore, a different but unique combination of the genetic material is actualized by MEIOSIS

Helpp me . Is it A,B,C,D

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Answer:

The answer is C. The GPS makes a task easier

Answer:

Its C

Explanation:

Grapes growing on a vine are observed to shrink slightly during the day and increase in size at night. This is because: a. developing fruits, such as grapes, transpire a lot of water to stay cool.
b. photosynthesis to produce sugar occurs in the light, but respiration and, therefore, the growth of new cells occurs mostly in the dark.
c. in leaves, phloem flow to growing sinks only occurs when the stomata are closed, because the transport capacity of the xylem is too small to supply water for both transpiration and phloem flow.
d. during the day, transpiration pulls on the water in the whole plant, causing the grapes to shrink slightly.

Answers

Answer:

b. photosynthesis to produce sugar occurs in the light, but respiration and, therefore, the growth of new cells occurs mostly in the dark.

Explanation:

Photosynthesis is the means by which green plants produce their foods by the use of sunlight, chlorophyll and carbon dioxide.

During the day, the grape make use of the process, photosynthesis, to get its sufficient food, thus the reason for the slight shrink. But at night, it respire well and new cells are produced. So that its size increase a bit.