Genetics 1
What are the sections of DNA that determine traits?
Genes
Who does history credit as the father of genetics?
Gregor Mendel
An organism's set of alleles, describing the variant of gene it has, is called what?
For example: a heterozygous (Tt) form.
Genotype
The physical appearance of an organism, the outer expression of its genotype, is called its what?
Phenotype
Brown eyes, tall, blonde hair are examples of which of the following terms?
Genotype, or Phenotype
Phenotype
When an organism reproduces, what is the new organism called?
Offspring
Which of the two kinds of alleles is expressed over the other?
The dominant allele
What is the number we cite when predicting the likelihood of inheriting particular traits, (or of other random events occurring?)
Probability
Which of the two kinds of alleles is masked, or hidden, by the stronger allele?
Recessive
What is the passing of genes from one generation to the next called?
Heredity
What is the study of genes?
Genetics
What is the model used to determine each possible genetic outcome (genotype) during sexual reproduction?
Punnett square
What kind of genotype has two of the same allele?
Homozygous (dominant (TT) or recessive (tt))
Before we can fill in a Punnett square, what information do we need about each parent?
Their genotypes
How would you describe the following genotype?
pp
Homozygous recessive
When two heterozygous (Tt) parents reproduce, how often are the offspring also heterozygous?
50% of the time or one out of two times
How would we describe the following genotype?
BB
Homozygous dominant
When Mendel crossed pure-breeding tall plants (TT) with pure-breeding short plants (tt), how often did the offspring express the dominant tall (T) allele?
100% of the time, or always
If an offspring is homozygous recessive (tt), which genotype will neither parent possess?
Homozygous dominant, (TT)
A genotype of Tt is an example of which of the following terms?
Homozygous recessive, homozygous dominant, or heterozygous?
Heterozygous
Which of the following represents a homozygous recessive genotype?
TT, Tt, or tt?
When Mendel crossed true-breeding tall plants (TT) with true-breeding short plants (tt), the offspring were all what genotype?
Heterozygous (Tt)
When a homozygous recessive (tt) parent is crossed with a homozygous dominant (TT) parent, how often will offspring have a homozygous recessive (tt) genotype?
0% of the time, or never.
How often will a child have recessive gray eyes if a homozygous recessive (tt) mother and heterozygous (Tt) father reproduce?
50% of the time, or one out of two times.
How often will the recessive trait be expressed when two parents with heterozygous genotypes (Tt) are crossed?
25% of the time, or one out of four times