Gcse Flashcards
(23 cards)
What are in DNA and what is it?
Gene = section of DNA
These make proteins
Where is DNA?
In the nucleus
What are different forms of genes?
Alleles
How many pairs of chromosomes are in a human?
46 pairs - including sex chromosome
Male XY and female XX
Chromosomes exist in ____ one p_____ and one m_____.
Chromosomes exist in PAIRS one PATERNAL and one MATERNAL.
What is a chromosome?
One strand of DNA
What is the role of DNA?
Code for making proteins that determine cell function
What is a dominant gene?
The one that is seen or affects the organism
What is a recessive
Not seen unless there is a pair (homozygous)
tt, dd, bb
What is homo
2 of the same e.g II, dd, DD
What is hetro?
2 different e.g Tt, Dd, Bb
What happens during genetic profiling?
DNA is cut into short pieces by enzymes, separated into bands and compared
What is the use of genetic profiling?
Criminal cases, paternity cases and in comparisons between species for classification identification of genes that are associated with disease.
What is the issues of genetic profiling?
Ethical issues of ownership and human rights
What is gamete formation?
Male and female sex cells
What is fertilisation?
Fusion (joining together of male and female gametes) restores the full number of chromosomes
What is a genotype?
This is the combination of alleles which controls the phenotype
What is a phenotype?
This is the physical characteristic/trait which can be seen
What is a gamete?
An egg or a sperm
What is an allele?
An alternative form of a gene
What is a recessive?
This allele will determine a characteristic only if there are no dominant ones
What is a homozygous?
This word refers to a pair of chromosomes being made of two of the same alleles or genes
What is a heterozygous?
This word refers to a pair of chromosomes being made of two different alleles
