Inheritence Flashcards
What is DNA
A massively long structure which super coils itself around proteins in the body in order to form chromosomes. These are ‘X-like’ structures which tidy up the nucleus.
Why do the DNA latch onto proteins in the body?
Because they are readily available
What is the purpose of super coiling.
It tidied up he nucleus due to tight coiling and allows everything to fit
Where are genes found?
On the chromosomes
Genes are bands on chromosomes
Female gene formation
XX
Male gene formation
XY
What determines whether the child will be a boy or a girl?
The sperm
Describe how genes, chromosomes and DNA are all linked
The DNA form chromosomes, which contain small structures called genes on them.
Where are chromosomes found
In the nucleus
How many chromosomes are there in most human cells
46
How many pairs of non sex chromosomes are there and what are their names
Autosomes
22 pairs
How many pairs of sex chromosomes are there?
One, labelled X and Y
A=
T
C=
G
On the structure of DNA, what does the s stand for
Sugar
On the structure of DNA, what does the p stand for
Phosphate
On the structure of DNA, what is G bonded with C labelled as
Nitrogenous bases
What is a base, bonded with sugar and phosphate labelled as?
A nucleotide
What is mitosis
A form of cell division that produces two identical diploid daughter cells from a diploid body cell, used for growth and repair in the body and in asexual reproduction. It occurs in all body cells apart from gametes.
What are the stages of mitosis
Interphase Prophase Metaphase Anaphase Telophase
(PMAT)
Mitosis chromosomes
Starts off with 46
Goes through DNA replication and has 92
Then separates into daughter cells which each have 46
Interphase
Before mitosis occurs
90 % of the cycle
DNA replication occurs in it (46-92)
This is because you have to duplicate the genetic material in the cell before splitting, or else they would not have the correct number of chromosomes.
Prophase
Nuclear envelope disintegrates
DNA supercoil to form chromosomes
The chromosomes take an X structure
Metaphase
Chromosomes attach to the equator of the cell ‘line up’