variation and inheritance Flashcards
what is a species?
a species is a group of organisms that can be in breed to produce fertile offspring.
how many types of variation is there?
2
what are the two types of variation?
continuous and discrete
what is the definition of a discrete variation?
a characteristic that is controlled by a single gene
what are examples of discrete variation?
eye colour, hair colour, blood group and earlobes
what is the definition of continuous variation?
a characteristic controlled by more than one gene
what are examples of continous variation?
hamdspand,height and mass
what kind of graph represents discrete variation?
a bar graph
what kind of graph represents continuous variation?
a histogram
are all characteristics controlled by genetics?
no many are effected by environmental factors
how is a persons height determined?
a persons height is determined by the genes they have and the availability of nutrients when they are developing
what are organism characteristics controlled by?
the genes it inherited from its parents
what is a gene?
a gene is a section of dna that codes for a proteins that controls a particular characterises eg eye colour or hair colours
how many copies goes an individual receive?
two
who do individuals inherited there copies from?
mum and dad
what is an allele?
an allele is alternative versions of a gene that can produce different characteristics
what are alleles for hair colour?
blonde brown black red
what are alleles for eye colour?
grey green blue brown
what are alleles for different hair types?
wavy straight curly
what are different alleles for blood group?
O A AB B
what are different alleles for dominant hand?
right left
what are different alleles for earlobes?
detached attached
what are dominant alleles?
a dominant alleles is where an individual inherits alan allel th at will always show that characteristic
what are dominant alleles represented by?
capital letters
what are recessive alleles?
recessive alleles only show if an individual inherits two copies of that allele?
what are recessive alleles represented by?
lowercase letters
what is a genotype?
the genotype of an organism is the genetics for a characteristics usually represented by leyters
what is a phenotype?
the phenotype of an organism is the physical appearance of a charectersituc
what is the definition of homozygous?
An individual who has inherited two different alleles of the same gene
what is the definition of hetrozygous?
An individual who has inherited the same allele for a gene
