Answer:
Thiamine pyrophosphate (derived from vitamin B1) is a coenzyme required for the activity of pyruvate dehydrogenase enzyme complex.
Explanation:
Pyruvate is the end product of glycolysis. During aerobic cellular respiration, pyruvate is oxidatively decarboxylated into acetyl CoA which in turn enters the Kreb's cycle. Oxidative decarboxylation of pyruvate is carried out by enzyme complex pyruvate dehydrogenase (PDH). The first step is simple decarboxylation and is catalyzed by pyruvate decarboxylase of the PDH complex.
The enzyme pyruvate decarboxylase and has a tightly bound coenzyme, thiamine pyrophosphate. Thiamine pyrophosphate is derived from vitamin B1. Lack of vitamin B1 in the human diet leads to beriberi that is characterized by an increased concentration of pyruvate in blood urine since oxidative decarboxylation cannot occur due to lack of the coenzyme thiamine pyrophosphate.
The given question says that a student has constructed a model of cellular transport using fences and several gates.
This model can be used to demonstrate the cellular transport.
The gates of the fences can be supposed as the protein pumps and the other fence demonstrates the lipid bilayer.
Let’s suppose in the fence, there are many cattles, and outside, there are less cattles, but the student open the gate and bring more cattles inside the fence. In this case, the transport of the cattles is similar to the active transport of the molecules using protein pumps. At cellular level, the energy for the active transport is provided by ATP molecules.
Now, let’s say, the student wants to feed the cattles with some nutrition rich food, which can help in maintaining the health of the cattles. The student fills his car with the cattle food and he enters inside the fence through gates. In this case, the food was not present in the fence, but was abundant in the outside environment, so, the diffusion would occur. But food cannot come self, without help of others, so, the movement is facilitated by the car, as it is done by the carrier proteins. Hence, it is an example of facilitated diffusion.
Answer:
The cell cycle is controlled by many cell cycle control factors, namely cyclins, cyclin-dependent kinases (Cdks) and cyclin-dependent kinase inhibitors (CKIs). Cyclins and Cdks, which are positive regulators of the cell cycle, activate cell cycle factors that are essential for the start of the next cell cycle phase.
Explanation:
Listen to pronunciation. (sel-SY-kul REH-gyoo-LAY-shun) Any process that controls the series of events by which a cell goes through the cell cycle. During the cell cycle, a cell makes a copy of its DNA and other contents, and divides in two.
Increased population size will result in the extinction of a species of organisms.
<h3>What is Extinction?</h3>
This is defined as the dying out or disappearance of species as a result of various factors.
When population size increases, it leads to unavailability of food and reduction of species due to starvation and death.
Read more about Extinction here brainly.com/question/1027555
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The answer is B An observation about the number or amount of something
