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Is agriculture really a net contributor of greenhouse gases?

The issue is that it is not always a cycle, when you drain wetlands or burn forests to make more farmland that's not a cycle that is permanent change. A change that can continue having effects for ...
John's user avatar
  • 14.8k
8 votes

Confusion about the duration of different phases of the cell cycle such as G1, G2 & S

It depends on the conditions, cell type or state of the cell. I don't think anyone here can do better justice to the question for a beginner than this web page. To show you why your answer is not ...
S Pr's user avatar
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6 votes

Is p53 a cyclin dependent kinase?

No, p53 and other tumor suppressor proteins do not belong to Cyclin dependent kinase(CDK)family. p53 blocks the cell cycle by promoting the synthesis of Cyclin dependent kinase inhibitors (CKI ...
Twinkle Sheen's user avatar
5 votes
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MCQ - Events in the Mitotic cycle

Cell cycle can be divided into two phases: 1. Interphase 2. M-phase(Mitotic phase) Note: M-phase can also mean Meiotic phase but it is not the full form of the acronym. So M-phase in mitosis has ...
Tyto alba's user avatar
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3 votes
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When does DNA replicate actually?

According to This paper and most biology textbooks, S-phase or synthesis phase is literally defined by the beginning and ending of DNA replication. The first picture does not accurately represent the ...
Joe Ruffatto's user avatar
3 votes

What is the meaning of "gap" in G1 phase?

The $G_1$ gap is the period between the last cell division and that start of DNA replication (synthesis). That's what "gap" means here. A period of time between two events. It's often described as ...
De Novo's user avatar
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3 votes

What is the meaning of "Rb is in the active state"?

The terminology of "Rb is active/inactive" refers to the activity of inhibiting E2F. So active Rb inhibits E2F, while inactive Rb doesn't inhibit E2F. With regard to Rb and phosphorylation - the ...
Oren Milman's user avatar
3 votes

Cell cycle arrest and apoptosis

Apoptosis can occur without cell cycle already being arrested. For instance, in the case of extrinsic apoptosis, which could be induced by T lymphocytes, for example, a trimeric receptor such as TNF-...
rotaredom's user avatar
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3 votes
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During interphase, is DNA wrapped around histones?

Yes, DNA is always wrapped around histones. DNA condensation using histones is not only meant to form the chromatids for mitosis/meiosis, but also one of the factors that control gene expression. ...
adjan's user avatar
  • 2,106
2 votes

How does the cell cycle affect stem cell fate?

If you are referring to cells that are differentiated in adults: Some somatic cells in multi-cellular organisms are post-mitotic, that is, the cells cannot divide, or said in other words, they don't ...
Figares's user avatar
  • 31
2 votes
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What determines the reversibility of cell of G0 phase in cell cycle?

The answer is quite complicated. One of the major issues in understanding what factors drive senescence vs quiescence has been the absence of a clear, uniform molecular definition of senescence. That ...
Ankur Chakravarthy's user avatar
2 votes
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Approximate Cell Doubling Time?

I figured it out, 32034/32 = ~1000 1000 / 5 = 200 hours Because 12*5=60 min = 1 hour
user3665690's user avatar
2 votes
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Contact Inhibition of Cell Division: Signaling Pathway

How does the mitotic entry machinery roughly respond to cell volume? This is a broad question but luckily there is one article that addresses this precise question in detail. However, it is very ...
WYSIWYG's user avatar
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2 votes
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Can mutation take place in G1 and G2 phases during the cell cycle?

Yes, it can. A mutation can potentially occur at any given moment in the cell cycle, not only in S phase, which is why revision mechanisms remain alert during the whole cycle. Such mechanisms not only ...
Luis Sierra's user avatar
2 votes

Mechanism for switch of embryonic stem cells from "fast" cell cycle to "normal" cell cycle?

This review (doi: 10.1534/genetics.118.301643) states that: Cell cycle progression in the early embryo is likely driven by a single CDK (CDK-1) in association with B-type cyclins. In support of this, ...
markur's user avatar
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2 votes
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How frequent are transposons in action?

To answer your first question and address the title of your post, see this review on active TEs in the human genome. Some excerpts: Although a large proportion (44%) of the human genome is occupied ...
acvill's user avatar
  • 8,296
1 vote

Interphase is the process in which DNA is duplicated/replicated and is the longest phase

It would be true, Because interphase takes about 90% of cell division and comes before Mitosis, and interphase contains three subphases, which are the following G1 - the Cell PREPS to preform DNA ...
Doddle's user avatar
  • 21
1 vote

quiescent stage (G0) occurs at the end of M phase or G1 phase:

Welcome to SE.Biology! It is often helpful to do a little internet research such as e.g. googling your question. I googled it and it gave me this image, which tells me that G0 cells leave from and re-...
Maximilian Press's user avatar
1 vote
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Chromosomal structures in S phase and Prophase

A comment by user AlwaysConfused has answered one part of the question, but I think that the OP's confusion is related to a point of language or teaching. The number of chromosomes doubles during S ...
Maximilian Press's user avatar
1 vote

Does a cell suspend or exit cell cycle at G0?

It is actually suspend and yes the words do differ. This is because the cells that enter the G0 stage is not actually exiting the cell cycle because when situation demands it will divide. It is ...
June's user avatar
  • 21
1 vote

Confusion about the duration of different phases of the cell cycle such as G1, G2 & S

A typical eukaryotic cell cycle is illustrated by human cells in culture. These cells divide once in approximately every 24 hours (Figure 10.1). However, this duration of cell cycle can vary from ...
bobkinch's user avatar
1 vote

Does meosis takes place in cell cycle?

This is a question of convention really. When people discuss the cell cycle, they usually refer to diploid cells (for diploid animals). So in your context, M stands for mitotic phase and does not ...
cagliari2005's user avatar
  • 2,903
1 vote
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Why don't cells double gene expression after S-Phase?

When the double strand is duplicated, the old strand (or, in other terms, the template) is methylated : this modification is enough to prevent the bind by the RNApol system and, by so, the ...
Shred's user avatar
  • 406
1 vote
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Flow Cytometry to learn about Cell cycle

The basis of analysing flow cytometry data in regard to the cell cycle is the fact that DNA synthesis occurs in S-phase and therefore cells before S-Phase (G0/G1) have half the amount of DNA compared ...
Nicolai's user avatar
  • 4,391
1 vote
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Cell cycle-regulated genes and mRNA

It is assumed that in order for a cell to divide it must progress through a series of gradual stages. At each of these phases certain proteins have to be manufactured through mRNA and/or modified post-...
Ana Maria Mendes-Pereira's user avatar

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