Topic 6- INHERITANCE VARIATION AND EVOLUTION Flashcards
What is DNA made of
DNA is made of nucleotides
what does each nucleotide consist of
each nucleotide has a sugar a phosphate group and one base
what are the four bases
A , T , C , G
What are mutations
mutations are changes to genetic code
what are the different types of mutations
insertions , a new base is inserted into a place where it shouldn’t be
Deletions , where a random base is deleted
substituted , when a base changes to another
what is sexual reproduction
involves the fusion of male and female gametes by meiosis
what is asexual reproduction
happens by mitosis, there’s only one parent so cell is genetically identical as there is no fusion of gametes
male chromosome pairs
x and y chromosomes
the y chromosomes causes male characteristics
female chromosome pairs
x and x chromosomes
the xx combination causes female characteristics to develop
what does genotype mean
your genotype is the combination of alleles you have
your phenotype is …
the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.
what is cystic fibrosis
a genetic disorder of the the cell membrane - caused by recessive alleles
what is polydactyl
a genetic disorder where a baby is born with an extra toe or finger - caused by dominant alleles
what is are environmental disorders
where the environment causes changes to an organism
what are mutations
mutations are changes to the sequence of bases in DNA
