Download Standard 9: The Genetics of Life Study Guide PART 1: Basic

Standard 9: The Genetics of Life Study Guide
PART 1: Basic Genetics
1.
What is the difference between a dominant allele and recessive allele? How do we represent the dominant alleles?
Recessive? ______________________________________________________________________________________
_______________________________________________________________________________________________
2.
Fill in the blanks in the chart below regarding pea shape
Genotype
Phenotype
Homozygous or Heterozygous
RR
Rr
Round peas
rr
3.
Which type of cells carry the traits that get passed on to the offspring – somatic or gametes? ________________________
4.
This principle states that the alleles for a trait separate when gametes are formed. These allele pairs are then randomly
united at fertilization. __________________________________________________________________________________
5.
This term applies to traits, such as hair or eye color, that’s controlled by more than 1 gene. __________________________
6.
If a pea plant were homozygous recessive for height (H), how would its alleles (genotype) be
represented?_________________
What is the phenotypic ratio of a monohybrid cross between two heterozygous parents? ____________________________
A cross between homozygous purple-flowered and homozygous white-flowered pea plants results in offspring with light
purple flowers. This demonstrates_________________________________________________________________________
When crossing a homozygous recessive with a heterozygote, what is the chance of getting an offspring with the
homozygous recessive phenotype? ________________________________________________________________________
7.
8.
9.
Use the Punnett square and description below to answer the following:
10. Purple flowers (P) is dominant over white flowers. Cross a homozygous white flower with a heterozygous purple flower
a. Predict the genotype for the parent organism whose genotype is unknown – write them on the Punnett square
b. Work out the Punnett square and the genotype & phenotype
Genotype
Phenotype
PART 2: Incomplete and Co-Dominance and Human Genetics
11. Which pair of sex chromosomes makes a person a male: XX or XY?
12. What is the difference between incomplete dominance and co dominance? ______________________________________
____________________________________________________________________________________________________.
13. Why can’t males be carriers of sex-linked disorders? Why are males more likely than females to exhibit a sex linked disorder
like be color blindness?_________________________________________________________________________________
____________________________________________________________________________________________________.
14. What is one example of a genetic disorder that can be seen on a karyotype? ______________________________________
15. What is the genotype of a female carrier of a sex-linked genetic disorder?_________________________________________
16. Colorblindness is a sex-linked trait. In the following punnett square cross a man who is colorblind with a female who is a
carrier.
Genotypic
Phenotypic
17. Complete the following punnett square regarding blood types. Use your key that was given to you in your notebook. Cross
a man with type O blood with a female with type AB blood.
Genotypic
Phenotypic
PART 3: Genetic Engineering
18. Organisms that have genes transferred from another species are called ________________________________________.
19. Explain the difference between genetic engineering and genetic diversity. What effect could genetic engineering have on
genetic diversity? _____________________________________________________________________________________
____________________________________________________________________________________________________
20. A __________________ is a diagram of family relationships that uses symbols to represent people and lines to represent
genetic relationships. Below is one of those diagrams. What does the diagram say?
_____________________________________________________________________________________________________
_____________________________________________________________________________________________________
_____________________________________________________________________________________________________
21. So you think you know it??? Try this: Black fur in mice (B) is dominant to brown fur (b) Short tails (T) are dominant to long
tails (t). What fraction of the progeny of the cross BbTt ´ BBtt will have black fur and long tails?
BT
Bt
Bt
bT
bt
BBTt
Bbtt
BBTt
Bbtt
Bt
Bt
Bt