Download 7th grade

7th grade
GENETICS
STUDY GUIDE
State Standards:
2a Students know the differences between the life cycles and reproduction methods of
sexual and asexual organisms.
2b. Students know sexual reproduction produces offspring that inherit half their genes
from each parent.
2c. Students know an inherited trait can be determined by one or more genes
2d. Students know plant and animal cells contain many thousands of different genes and
typically have two copies of every gene. The two copies( or alleles) of the gene may or
may not be identical, and one may be dominant in determining the phenotype while the
other is recessive.
2e. Students know DNA is the genetic material of living organisms and is located in the
chromosomes of each cell.
Vocabulary:
Heredity
Genetics
Dominant
Recessive
Phenotype
Genotype
Homozygous
Heterozygous
Gene
DNA
Chromosome
Probability
Allele
1. Explain Mendel’s experiment with pea plants..
2. Fill in this square with the following information:
Cross a heterozygous orange-flowered plant (Oo) with a homozygous purple-flowered
plant(oo). Orange is dominant and purple is recessive.
a. What is the ratio of orange to purple?
b What are the genotypes of the offspring?
c. What are the phenotypes of the offspring?
3. On a Punnett square, a capital letter stands for a ________allele, a lower case letter stands
for a ________ allele.
4. What are the combinations of alleles that are possible for a dominant trait?
5. What are the combinations of alleles possible for a recessive trait
6. Where is the DNA found in the nucleus of a cell?
7. What are the 4 nitrogen bases that make up the rungs of the DNA ladder?
8. What are the combinations of nitrogen bases?(what fits with what)