Vocabulary
What is the definition of a dominant allele?
the allele or trait that shows up
Describe incomplete dominance
No allele is dominant over the other, phenotype is a mix of the two
What is selective breeding?
humans choose the traits they want to come out in plants and animals
BB, Bb
What is it when a gene is not copied correctly or altered?
mutation
What is a phenotype?
the physical attribute those shows up based on the genotype
If one dominant allele is present in the genotype then the trait is represented in the ________.
phenotype
What is natural selection?
Nature chooses the outcome, "survival of the fittest"
Complete this cross: Tt and tt. What are the percentages for each outcome?
50% Tt and 50% tt
Parent 1 and parent 2 both do not have sickle cell anemia, but they have a baby who does have sickle cell anemia. Example how this is possible.
Both parents carried the recessive allele for sickle cell anemia and passed it to the child
What is heterozygous and give an example?
You have one dominant and one recessive allele, hybrid, Hh
Which is an acquired trait?
A. the wing shape of a butterfly
B. the number of zebra stripes
C. teaching sign language to a monkey
D. how tall a flower stem grows
C. teaching sign language to a monkey
What is one disadvantage of artificial selection?
loss of genetic variety, disease, time consuming, lead to extinction
A hyrbrid brown rat is crossed with another hybrid brown rat (black is recessive). What are the chances the offspring is brown and what are the chances the offspring is black?
75% brown and 25% black
Give an example of a gender linked disorder
color blindness, hemophilia, muscular distrophy
What is a purebred and give an example?
both alleles are the same in a genotype such as both dominant or both recessive, JJ or kk
A cow has a coat color gene where red hair and white hair are co-dominant. This means both traits appear at the same time in the offspring. When a red cow and a white cow have a calf, the calf has both red and white hairs mixed together, called a roan coat. Why does the calf have both red and white hairs instead of just one color?
Because in co-dominance, both alleles are expressed equally, so both the red and white hair traits appear in the calf.
What is one advantage of artificial selection?
produce more, larger/smaller breed, insect resistant, drought resistant
If I have 12 blue eyed (B) offspring and 4 brown eyed (b) offspring which statement could be true?
A. If both parents were BB then all the offspring would have brown eyes.
B. If both parents were bb then all the offspring would have blue eyes.
C. If one parent is BB and the other parent is bb then a majority of the offspring would have blue eyes.
D. If one parent is BB and the other parent is Bb then a majority of the offspring would have blue eyes
D. If one parent is BB and the other parent is Bb then a majority of the offspring would have blue eyes
How do genes pass physical traits from parent to offspring?
Genes are pieces of DNA that carry instructions for traits. Parents pass their genes to their offspring during reproduction. Each offspring gets half of their genes from their mother and half from their father. These genes determine physical traits like eye color, hair color, and height.
What is a trait?
a characteristic of an organism that is determined by genes
Explain co-dominance and give an example
Co-dominance is when both alleles show up. For example, a pink flower and white flower cross to make an offspring with both pink and white coloration.
Farmers sometimes choose plants with the biggest fruits and breed them together so the next generation will also grow large fruits.
What is this process called, and why do farmers use it?
selective breeding/artificial selection because they picked a specific trait to come out (larger/smaller, more, faster growth, more resistant to disease or drought)
If a purebred dominant brown eyed crossed with a homozygous brown eyed, what are the chances the offspring with have brown eyes? Use the letter C.
0% brown eyes
Where are genes located?