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Where are genes found in a cell? a. Cytoplasm b. heterozygous c. chromosomes
c. chromosomes
How many copies of each gene do you inherit? a- 23. b-1. c.4. d.2
d. 2 — one from each parent
Give an example of two alleles for eye colour. Use letters and explain them.
Brown (B) and blue (b)
If a plant has alleles T and t for height, what does each allele represent? T is for what and t is for what?
T = tall, t = short
Can two organisms have the same phenotype but different genotypes? yes or no explain
Yes — BB and Bb both produce the same dominant trait
How do you write a genotype for a recessive trait?
Using two lowercase letters, e.g. bb
What is the phenotype of a mouse with alleles bb for fur colour (b = white)?
White fur
Which is visible — genotype or phenotype?
Phenotype
Give an example of a homozygous dominant genotype. LETTERS
BB
Give an example of a homozygous recessive genotype. LETTERS
bb
If an organism’s genotype is Tt, is it heterozygous or homozygous?
Heterozygous
Why does a heterozygous individual show the dominant trait? 1- The dominant allele masks the recessive allele 2- The recessive allele is not present
1- The dominant allele masks the recessive one
Can a heterozygous individual pass on a recessive allele? yes or no
Yes
If a child shows a recessive trait, what do we know about the parents? 1- Both parents have dominant alleles 2- Both both carried at least one recessive allele
2-They both carried at least one recessive allele
What happens when a dominant allele is present? 1- Never expressed 2-Always expressed
2- Always expressed
What information do you need to set up a Punnett square? 1-Phenotype of both parents 2- Genotype of both parents
2-The genotypes of both parents
