1 Write the important aspects about the overall
chemical equation of respiration, pertaining to the following.
(1) number of steps for glucose to break down into CO2 and H2O.
(il) involvement of enzymes.
(ili) forms of energy liberated.
2. List three ways in which respiration is different
from burning.
3. Name the three inlets of oxygen for respiration
in plants... PLs help me in return I'll mark u brainlist...
Answers
Answer:
Glycolysis is a series of reactions that extract energy from glucose by splitting it into two three-carbon molecules called pyruvates. Glycolysis is an ancient metabolic pathway, meaning that it evolved long ago, and it is found in the great majority of organisms alive today
In organisms that perform cellular respiration, glycolysis is the first stage of this process. However, glycolysis doesn’t require oxygen, and many anaerobic organisms—organisms that do not use oxygen—also have this pathway.
Highlights of glycolysis
Glycolysis has ten steps, and depending on your interests—and the classes you’re taking—you may want to know the details of all of them. However, you may also be looking for a greatest hits version of glycolysis, something that highlights the key steps and principles without tracing the fate of every single atom.
Glycolysis takes place in the cytosol of a cell, and it can be broken down into two main phases: the energy-requiring phase, above the dotted line in the image below, and the energy-releasing phase, below the dotted line.
Energy-requiring phase. In this phase, the starting molecule of glucose gets rearranged, and two phosphate groups are attached to it. The phosphate groups make the modified sugar—now called fructose-1,6-bisphosphate—unstable, allowing it to split in half and form two phosphate-bearing three-carbon sugars.
. In this phase, each three-carbon sugar is converted into another three-carbon molecule, pyruvate, through a series of reactions. In these reactions, two
molecules and one
molecule are made. Because this phase takes place twice, once for each of the two three-carbon sugars, it makes four
Each reaction in glycolysis is catalyzed by its own enzyme. The most important enzyme for regulation of glycolysis is phosphofructokinase, which catalyzes formation of the unstable, two-phosphate sugar molecule, fructose-1,6-bisphosphate
. Phosphofructokinase speeds up or slows down glycolysis in response to the energy needs of the cell.
Overall, glycolysis converts one six-carbon molecule of glucose into two three-carbon molecules of pyruvate.
.
Detailed steps: Energy-requiring phase
We’ve already seen what happens on a broad level during the energy-requiring phase of glycolysis. Two
ATP
s are spent to form an unstable sugar with two phosphate groups, which then splits to form two three-carbon molecules that are isomers of each other.
Next, we’ll look at the individual steps in greater detail. Each step is catalyzed by its own specific enzyme, whose name is indicated below the reaction arrow in the diagram below.
Step 1. A phosphate group is transferred from
to glucose, making glucose-6-phosphate. Glucose-6-phosphate is more reactive than glucose, and the addition of the phosphate also traps glucose inside the cell since glucose with a phosphate can’t readily cross the membrane.
Step 2. Glucose-6-phosphate is converted into its isomer, fructose-6-phosphate.
Step 3. A phosphate group is transferred from
to fructose-6-phosphate, producing fructose-1,6-bisphosphate. This step is catalyzed by the enzyme phosphofructokinase, which can be regulated to speed up or slow down the glycolysis pathway.
.
Here, we’ll look in more detail at the reactions that lead to these products. The reactions shown below happen twice for each glucose molecule since a glucose splits into two three-carbon molecules, both of which will eventually proceed through the pathway.
Glycolysis
This is because oxidation in glycolysis doesn't involve oxygen atoms. It's just movement of hydrogen.
The ATPs originally came from your mother through parental nutrition, while you where developing in the womb. When you are born you will have a stock pile of ATP in your body, which must be replenished to stay alive. The body has many ways to make ATP, which can be seen by looking at the vast amount of metabolic reactions that occur with the body. This is also why we can survive for a long time without any additional consumption of food as the many catabolism pathways in the body that breakdown larger molecules and transfer the energy from the breakdown to ATP.
One important note is that the enzyme that catalyzes the reaction phosphofructosekinase is what actually speeds up or slow downs glycolysis. Once fructose-1,6-bisphosphate is formed it will be broken down to the two carbon molecules at the same speed. The way it is speed up or slowed down is due to phosphofructosekinase the enzyme that catalyzes the reaction to create fructose-1,6-bisphosphate is regulated by both ATP and ADP, when ATP levels are high it is inhibited and less fructose-1,6-bisphosphate will be created when ADP levels are high it will be activated and more fructose-1,6-bisphosphate will be created.
Explanation: