Vocab
The genetic makeup, or the letter.
Genotype
A gene that is hidden when a dominant trait is present
recessive
What is the tool that is used to predict possible offspring?
Punnett Square
Who is the man who first experimented to discover how traits are passed down?
Gregor Mendel
Where is DNA found? Be more specific than the nucleus....
chromosomes
The physical expression of traits.
Phenotype
The gene that will always be shown if it is present.
Dominant
If you have one dominant allele and one recessive allele, which trait will show?
Dominant
Having freckles is dominant to not having freckles in humans. Using the letter F, cross a homozygous male with freckles with a female who has no freckles. Will any of their offspring not have freckles?
NO
What are the four bases pairs of DNA?
A T C G
The passing of traits from parent to offspring.
Heredity
The combination of genes that codes for a specific trait.
Genotype
B = pointy ears and b = floppy ears. Cross a heterozygous pointy eared dog with a floppy eared dog. Show your work in your punnett square. What percentage of offspring would have pointy ears?
50%
In fish, soft scales are dominant to hard scales. Using the letter S, create a punnett square crossing two heterozygous fish. Give percentages of offspring being homozygous dominant, homozygous recessive, and heterozygous.
25% homozygous dom
50% heterozygous
25% homozygous recessive
How do you remember the four base pairs?
Apples in a tree, cars in a garage
Structures made of DNA, located in the nucleus.
Chromosomes
What is the difference between homozygous and heterozygous?
Homozygous will show the same letters (either AA or aa). Heterozygous will show different letters (Aa)
P = purple and p=pink. Complete a punnett square for a homozygous purple flower crossing with a heterozygous flower. What is the percentage that the offspring would be pink?
0%
In horses, the dominant color is brown and the recessive color is grey. Using the letter G, create a punnett square crossing a grey horse with a heterozygous horse. Give percentages of homozygous dominant, homozygous recessive, heterozygous.
50% heterozygous
50% homozygous recessive
What are the three things that DNA is made out of? This is including the outside of the ladder and the middle 'steps'
Sugar, phosphate, nitrogen bases
Different forms of a gene
Allele
Give an example of a homozygous recessive allele pair:
any two of the same lowercase letters.
B = brown eyes and b = blue eyes. Cross a blue eyed male with a blue eyed female using a punnett square. What is the percentage that their offspring will have brown eyes? What is the percentage they will have blue eyes?
100% blue eyes
0% brown eyes
In cats, having a curly tail is dominant to having a straight tail. Using the letter T, cross a homozygous curly tailed cat with a straight tailed cat using a punnett square. What are the chances of the offspring having a curly tail?
100%
What can genetic mutations be considered?
harmful, helpful, neutral