Why is the chromosome important?
To put it simply, chromosomes are important because they contain the entire (or at least the vast majority of) genetic information for an organism. The organism's DNA is contained within the chromosome as a long series of nucleotides that are organized into genes.
Chromosomes are thread-like structures located inside the nucleus of animal and plant cells. Each chromosome is made of protein and a single molecule of deoxyribonucleic acid (DNA). Passed from parents to offspring, DNA contains the specific instructions that make each type of living creature unique.
- The Function of Chromosomes. Chromosomes are the thread-like structure found in the nuclei of both animal and plant cells. They are made of protein and one molecule of deoxyribonucleic acid (DNA).
- In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure.
- A gene is the basic physical and functional unit of heredity. Genes, which are made up of DNA, act as instructions to make molecules called proteins. In humans, genes vary in size from a few hundred DNA bases to more than 2 million bases.
In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Twenty-two of these pairs, called autosomes, look the same in both males and females. The 23rd pair, the sex chromosomes, differ between males and females.
- Sex cells only contain one chromosome from each pair. When an egg cell and sperm cell join together, the fertilised egg cell contains 23 pairs of chromosomes. One chromosome in each pair comes from the mother, the other from the father.
- 1q21.1 deletion syndrome or 1q21.1 (recurrent) microdeletion is a rare aberration of chromosome 1. A human cell has one pair of identical chromosomes on chromosome 1. One chromosome has the normal length and the other is too short.
- Chromosomes are thread-like structures located inside the nucleus of animal and plant cells. Each chromosome is made of protein and a single molecule of deoxyribonucleic acid (DNA). Passed from parents to offspring, DNA contains the specific instructions that make each type of living creature unique.
The DNA of most bacteria is contained in a single circular molecule, called the bacterial chromosome. The chromosome, along with several proteins and RNA molecules, forms an irregularly shaped structure called the nucleoid. In addition to the chromosome, bacteria often contain plasmids – small circular DNA molecules.
- Video: Bacterial Chromosome: Definition & Structure. You have chromosomes in your cells that allow you pass on genetic information, and so do bacteria. Bacteria have single, circular chromosomes, along with extra pieces of DNA called plasmids. The chromosomes and plasmids store all of a bacterium's DNA.
- Inclusions are stored nutrients, secretory products, and pigment granules. Examples of inclusions are glycogen granules in the liver and muscle cells, lipid droplets in fat cells, pigment granules in certain cells of skin and hair, water-containing vacuoles, and crystals of various types.
- bacteria do not have a membrane-bound nucleus, and their genetic material is typically a single circular bacterial chromosome of DNA located in the cytoplasm in an irregularly shaped body called the nucleoid. The nucleoid contains the chromosome with its associated proteins and RNA.
Updated: 18th November 2019