Answer:
(46)
Explanation:
in a humans, each cell normally contains 23 pair of chromosomes, for a total of 46, these pairs, called autosomes, look the same in both males and females.
Answer:
The correct answer is option d. "A region of DNA sequence upstream of a gene where transcription factors bind".
Explanation:
Cis-regulatory elements (CREs) are fragments of DNA that do not encode to a protein, but regulate the transcription of nearby genes. CREs regulation is based on binding to transcription factors. These elements are vital for the regulation of complex molecular mechanisms that involve the participation of multiple genes. Additionally, CREs could participate in pleiotropy (a single gene being responsible for the development of multiple traits), because a single transcription factor could bind to different CREs.
Answer:
True
Explanation:
Cell cycle checkpoints are an important layer of control of the cell cycle. The cell cycle is a process by which cells divide.
There are 4 stages of the cell cycle G1, G2, S and M.
When the cell goes through the cell cycle, each stage has different processes that must occur for the cell to properly divide. During G1, the cell must grow to sufficient size and the environment must be favorable for cell division. During S phase, all the DNA must be properly replicated. during G2 the cell must prepare for division. During M, the cell actually divides.
There are 3 checkpoints throughout the cell cycle. The G1 checkpoint ensures the cell has reached sufficient size. The G2 checkpoint ensures the DNA has been properly replicated. The M checkpoint makes sure the chromosomes are properly attached to the spindles to split the DNA between 2 new cells.
Without these checkpoints, the cell can divide uncontrollably which can lead to cancer.
Which of the following statements describes
B. This zone measures from 600 to 3,000 feet below the surface, and is sometimes referred to as the “twilight zone” because of the amount of ambient light available.
