Biology
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Chromosomes

Chromosomes

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Chromosomes

Chromosomes are like long chains of DNA found in the nucleus of cells. Humans have 46 chromosomes in total, which are arranged in 23 pairs. These pairs are also called sex chromosomes. However, the number of chromosomes can differ depending on the organism. In humans, the 23rd pair of chromosomes is a bit different from the rest.

Nucleus

Most of the cells in your body have a nucleus that acts as the cell's central nervous system and controls its internal activities. The nucleus contains structures called chromosomes that store genetic material. 

Genes

Women have two X chromosomes, whereas men have one X and one Y chromosome, making them separate chromosome pairs (XY). This is due to the fact that the X chromosome contains many more genes than the Y chromosome, with many of these genes having functions beyond determining sex and not having a counterpart on the Y chromosome. Genes are the component of us that are responsible for all of our unique traits, and different genes regulate the development of certain traits, such as hair and eye color. X-linked genes have distinct inheritance patterns because they are present in different numbers in females (XX) and males (XY). In genealogy, the male lineage is often traced using the Y chromosome because it is only passed down from the father [^4]. In rare cases, a male baby can receive an extra Y chromosome in each of their cells, resulting in an XYY.

DNA

Large and complicated DNA molecules are present. They carry the genetic material that establishes a living thing's traits.

Phosphate and deoxyribose sugar units alternate to form the DNA double helix's backbone. The two sides are held together by interconnecting bases.

DNA has four distinct bases:

·       A =adenine

·       T = thymine

·       C = cytosine

·       G = guanine

A and C complement each other because T and G are theiropposites, respectively. The base-pairing rule is used to describe this.

One base, one sugar, and one phosphate make up anucleotide.

The DNA of every person is distinctive. No one else has thesame base order as them, with the exception of identical twins.

Chromosomes

Chromosomes are typically only visible under a light microscope during the metaphase of cell division, when they are aligned in the center of the cell in their condensed form. Before this happens, each chromosome is duplicated, and both copies are joined by a centromere, which results in either an X-shaped structure if the centromere is located equatorially, or a two-arm structure if the centromere is located distally. A metaphase chromosome is an X-shaped structure that forms during metaphase and is highly compressed, making it the easiest to recognize and study. Chromosomes are most compacted in animal cells during the chromosome segregation process known as anaphase. Studying chromosomes is important for understanding genetic diseases, genetic variation, and evolution.

Summary Questions

Where in the cell are chromosomes found?

The nucleus

What molecule are chromosomes made up of?

DNA

What are the four bases of DNA?

DNA has four distinct bases:

·       A =adenine

·       T = thymine

·       C = cytosine

·       G = guanine

 

What are genes?

Genesare the component of us that are responsible for all of our unique traits.

What do we need different genes for?

Different genes regulate the development of certain traits, such as hair and eye color.

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