Download ____ Name Basic Genetics Review Draw a picture that shows

# ____
Name ______________________________
Basic Genetics Review
1. Draw a picture that shows fertilization in an animal.
- You should draw each of the following in your picture:
Sperm, egg, zygote, embryo, fetus, and offspring.
- You should write the following in your picture where each makes sense:
Haploid, diploid, fertilization, gametes, 23 chromosomes in a human, 46 chromosomes in a
human.
2. Explain how identical twins could result in the process above:
3. Explain how fraternal twins could result in the process above:
4. what is the difference between identical and fraternal twins?
5. What is interesting about the fetus of various animals?
6. What is the male and female gamete in plants?
7. Explain what results from the process of meiosis:
8. How are the resulting cells of meiosis different in males as compared to females?
9. Explain how dominant genes and recessive genes work with each other:
10. What is the difference between a genotype and a phenotype?
11. What is the difference between homozygous and heterozygous?
12. Write an example of a homozygous genotype:
13. Write an example of a heterozygous genotype:
14. If your teacher writes some information about a person’s traits on the board. How do you know when
they are writing down information about genotype and when they are writing info about a phenotype?
15. For each of the following, tell if it is a genotype or a phenotype:
a. TT
b. blue
c. homozygous dominant
d. tall
e. heterozygous
16. Are there more possible genotypes for having a dominant genotype or a recessive genotype? EXPLAIN
17. How can two dark haired parents end up with a blonde kid?
18. Organisms have two alleles for each trait that they received from their parents. How many of each pair
of alleles will a sexually reproducing organism pass on to their offspring?
19. Write the genotype for each of the following phenotypes:
a. homozygous dark hair
b. heterozygous dark hair
c. albino (recessive)
20. What fraction of the kids (if any) of the kids from two albino parents will have regular body skin tone.
Albinism is recessive. (Use a punnett square.)
21. a) In pea plants yellow pea alleles dominate over green pea alleles. If one pea plant that is heterozygous
is crossed with a plant with green peas, what fraction of the offspring will have green peas? (Use a
punnett square.)
b) About how many plants out of 1000 created from these parent plants would have yellow peas?
c) What is the genotypic ratio of the offspring in this situation?
22. What is a pedigree?
23. Imagine and make up a simple pedigree for a person with parents, grandparents, some aunts and
uncles, a few cousins, and a niece. Draw the pedigree below:
Label how everyone is related to your main person in the pedigree:
Make up and draw in the genotype for hair color for each person in your pedigree above. Your
genotypes should make sense considering what genes each parent has to give to their kids!
24. Pull out your “Human Traits” assignment. Look it over and describe the following about the five traits
you find to be most interesting:
a) Trait –
Dominant or Recessive?
Genotype(s) you would need to have what you consider to be the least favorable phenotype b) Trait –
Dominant or Recessive?
Genotype(s) you would need to have what you consider to be the least favorable phenotype c) Trait –
Dominant or Recessive?
Genotype(s) you would need to have what you consider to be the least favorable phenotype d) Trait –
Dominant or Recessive?
Genotype(s) you would need to have what you consider to be the least favorable phenotype e) Trait –
Dominant or Recessive?
Genotype(s) you would need to have what you consider to be the least favorable phenotype 25. a. When Mendel was discovering the rules of genetics, he did not know about alleles and pairs of
homologous chromosomes. Explain why he would have been confused at first by the results of breeding
a homozygous tall plant with a short plant?
b. If he took some of the offspring from the above cross, why would he have been confused again?
26. If a pea plant has a genotype of Yy tt Rr?