Variation and inheritance Flashcards
What is the meaning of variation?
It means having different characteristics
What is continuous variation?
When characteristics shows a continuous range of values between a minimum and a maximum?
What is the meaning of polygenic?
A characteristic which is controlled by more than one gene
What are examples of continous variation in humans
skin colour, height, human heart rate, etc
What are examples of contiuous variation in plamts?
Seed mass
Would polygenic features show continous or discrete variation and why?
continous variation, because these characteristics shows a continous range of values
What is discrete variation?
Variation where measurements fall into distinct groups
What is discrete variation controlled by?
One gene
What are examples of discrete variation?
Blood group type, eye colour, hair colour
What are genes a part of?
Chromosomes
What is a monohybrid cross?
Genetic cross involving one characteristic
Whta is a phenotype?
The physical appearance of an organism
What is a genotype?
The set of alleles an organism possesses
What is a gameate?
Sex cells
What are alleles?
Different forms of the same gene eg blue or brown for eye colour
What is the meaning of dominant?
Allele which is always expressed in the phenotype .Represented by capital letter
What is the menaing of recessive?
Allele which i sonly expressed inthe phenotype when tow are present. Represented by lower case letter
What is P1?
Parents of the cross first generation second generation
Human gametes cells contain this number of chromosomes?
23
Human liver and heart cells contain this number of chromosomes
46
What is the meaning of homozygous?
Both alleles are identical
Whta is the word for when both alleles are identical?
Homozygous
WHt is the meaning of heterozygous?
alleles are different
What is the word for when allels are different?
Heterozygous
