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Flashcards in DNA Deck (12):

What does DNA stand for?

Deoxyribonucleic acid


What is DNA?

DNA is the molecule that determines characteristics. The molecules their made up of are called nucleotides. Nucleotides have 3 main parts: phosphate group, deoxyribose sugar and 1 of 4 nitrogen - rich bases.


What are complimentary base pairs?

Complimentary base pairs is when the chemical structure of a DNA can only form chemical bonds with one of the other bases.


What are genes?

Genes are sections of DNA, each chromosome can be made up of over 1000 genes.


Describe the process of replicating DNA

First the strands of the double helix seperate from each other like the way a zip opens. Secondly the nucleotides from the DNA chain pair up with unfolded bases on the double helix (following the rule of complimentary base pairs). Thirdly the sugar and phosphate molecules bond with the neighbouring nucleotides and new strands of DNA are formed.


What bases are paired?

Adenine (A) and Thymine (T) are paired.
Cytosine (C) and Guanine (G) are paired.
A&T or T&A and C&G or G&C.


What are chromosomes?

Chromosomes are long, thin structured found in the nucleus of a cell. Chromosomes are made up of DNA and protein. There are 46 chromosomes in each cell, when there are less or more it is a birth defect (Down syndrome etc)


Describe mitosis

Mitosis is a type of cell division that produces 2 daughter cells that are identical to the parent cell. This type of cell division involves the growth and repair of the body.


Describe meiosis

Meiosis produces sperm and egg that have half the the number of chromosome of the parent cell (23)


What are the 2 types of cell division?

Mitosis and meiosis


What is heterozygous and homozygous?

Heterozygous is when it is Rr (2 different)
Homozygous is when it is RR or rr (2 the same)


What are the genes of male and female?

Female is XX and male is XX.