Revision notes Flashcards
define the term autosome
every chromosome in a gamete and somatic cell that is not a sex cell.
what is another word for a somatic cell?
Diploid cell
what is another word for a gamete cell?
Haploid cell
How are nucleotide groups arranged in?
A double helix
state three ways homologous chromosomes are the same.
-their length is the same
-centromere appears in the same location
-the pattern of the genes is in the same order down their length.
what are the 3 components that make up a nucleotide group?
-nitrogen rich base
-deoxyribose sugar
-phosphate group
what are TWO ways genes differ?
-their length can change
-combination of base pairs (arrangement of A and T, C and G)
state the term used to describe different versions of the same gene?
Alleles.
how many daughter cells are produced by the mitosis process?
2 genetically identical cells.
how many daughter cells are produced by the meiosis process?
4 genetically unique cells.
What does A stand for in the mitosis/meiosis method?
Anaphase (Apart)
Where does meiosis process take place in females?
Ovaries.
what is the term given to a condensed form of DNA when preparing to replicate.
Chromosome
what is the term used to describe a large molecule made up of many smaller repeated units.
Polymer
how do you spell this?
adinene
adenine
adenine
adinine
Adenine
How does DNA replicate using the unzip method
The DNA double helix begins to unzip from the top this exposes the nitrogen rich bases to the rest of the nucleus. free nucleotide groups within the nucleus begin to hydrogen bond with their complimentary base pair (A,T and G,C). this process continues down the length of the DNA molecule until there are two identical DNA strands. Finally the phosphate groups and the deoxyribose sugar groups chemically bond together to form the outer two spirals of the DNA polymer.
What is the process of one cell dividing to make two identical cells?
mitosis
what is the rule that describes how nitrogen rich bases bond with another.
Complimentary base pairs
State one job that the special complex molecules perform.
Move/Create chemicals
half of a chromosome is called…
Chromatid
what is in the middle of a chromatid
Centromere
two components that make up a chromosome
DNA and Protein
Phosphate and deoxyribose groups are chemically bonded together.
true or false
True
are G and A complimentary base pairs?
No, A can only bond with T, and G can only bond with C.
what is the first step on DNA replication?
Double helix begins to unzip
DNA for an turtle adenine is 28% what are G, C, and T.
Guanine is 22%
Thymine is 28%
Cytosine is 22%
As all of the bases have to add up to 100%.
Chromatid is 2 strands of a chromosome after replication.
True or false.
False, as a chromatid is one strand of chromosome after replication.
2n can be called…
A diploid/somatic cell
what is the last chromosome in a human cell?
A sex chromosome that determines the gender.
meiosis is the process used to…
create more gamete cells.
what is the first step in the mitosis/meiosis cycle?
Prophase.
in mitosis how do the chromosome line up in metaphase
One on top of the other down the middle of the cell
how does an uncondensed chromosome form back to a chromosome.
to form back to a chromosome it coils tightly around proteins called histone.
do gamete cells come in pairs?
no, gamete cells are single and can be called n.
homologues meaning?
DNA that is similar or identical to an other chromosome.
what does Allele do
gene instruction but can be different for example eye colour.
homologues have the same underlying structure but different appearances and functions.
true or false
True
A sheep has 54 chromosomes in each muscle cell. what is its diploid and haploid number?
Diploid = 54
Haploid = 27
