This is a picture of the 23 pairs of chromosomes in the human.
The chromosomes seem to have a very basic structure how ever this is not the case chromosomes have a very complicated structure.However the same is characterised and the 23 pairs of chromosomes all follow the same simailarties in look only the size and thickenss vary in looks. Chromosomes are long thin structures, . Showwhere on the chrormsonme is a very narrow region which is known a s a centromere. Scientists who study chromosomes use three clues to tell chromosomes apart:
- Characteristic banding patterns (caused by staining the chromosomes with dyes)
- Position of the centromeres
- Chromosome size
Chromosomes always occur in pairs, basically they appear in homoglous pairs, which means they will have the sam egene loci. The reanson chromosomes exist in pairs is because one chromosome of each pair was inherited from one of the parents.
The number of chromosomes is always set for each speciss. They will varies from other organiosm , however with the particular species remain the same i.e humans have 46 chromosomes , however onion cell have only 16chromosomes.
Other important feature that chromosomes share is that they copy them selves. During intephase the chromosomes ar busily replicating them selvees. It creates two identical structures called chromatid s. They will remain attached until anaphase.
Chromosomes are very important because they carry out important instructions and hold essential and vital information. We know that the DNA holds the important information that code for protein. The total length of the DNA of the human chromosome sis over 2 meters, shared between the 4 6 chromosomes . It is important to know that the half the number of chromosomes in an orgainsim came from each parent. As the chromosomes contain all the geneic information, it also has the job of controlling cell activity. This means it is incharge of the organisims characteristics and transmit these to subsequently generations.
Chromosomes are also involved in the reproduction . Reproduction involves the multi explication of cells. In odder to divide cells under division. In any description of cell divine the chromosomes occupy a central position. As the vehicles of hereditary they determine the characteristics of the and its offspring, and it is essential that they should be correctly distributed between the daughter cells. Two types of cell division are recognised according to the behaviour of the chromosomes. In the first of theses, the daughter cells are the same as the parent cell, mitosis. In the second the chromosomes numbers become halve, this is called mimesis. When the cytoplasm divides in mitosis, cytokines is, the chromosomes are the important sutures, which provides the essential information for their new organelles.
Chromosomes can also mutate Different types of mutations with letters on the chromosomes representing different genes. These can have different effects on the organism. This help to show just how important chromosomes, as they do hold all the genetic information.
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Point mutation: Mutation of a single nucleotide pair or a very small part of a gene.
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Deletion: The chromosome breaks in two places and a segment is missing when the breaks heal.
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Translocation: Two chromosomes break at different points. When the deleted gene from one chromosome attaches to the other chromosome, chromosomes with more or fewer copies of normal genes result.
Those mutations can have different consequences:
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Lethal: cause the organism's death
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Conditional: produce a phenotypic effect under certain conditions
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Loss of function: reduce the activity of a gene
Gain of function: increase the activity of a gene
So overall we can state that the chromosomes are the most important organisms that exist in our body and that are so important that change in one of the base pair, in the e DNA it can change/effect the whole organisim.