1. Heredity and Reproduction
7th Grade FCAT 2.0 Review
Heredity and Reproduction

2. What determines the traits that offspring will inherit?
Essential Question
What determines the traits that offspring will inherit?

4. Review: Explore Homozygous dominant= Homozygous recessive=
Alleles-multiple forms of a gene you inherit (one comes from mom and comes from dad)
Using the letter B, write alleles for the following:
Homozygous dominant=
Homozygous recessive=
Heterozygous BB bb Bb

5. Review/Explore (Extra)
Determine an example for the terms below.
Phenotype=physical description
Genotype=genes
Tall Tt

6. Explore
In chickens, brown feathers are the dominant phenotype and yellow are the recessive phenotype.
What genotype will result if you cross two heterozygous chickens?
Circle the genotype that will result in brown chicks B b
BB Bb
Bb bb

7. Explore In lemmings, the trait for albinism is recessive.
If you cross two heterozygous lemmings what genotypes will result?
Circle the genotype that will result in carriers of the albino trait, but are not actually albino. A a
AA Aa
Aa aa

8. Explore
Select 2 of the offspring genotypes from question2 that would result in a better than 25% chance of having albino offspring. A a
Aa aa
Aa aa

9. Explain:
The pedigree below shows how family members are related and which individuals have the make-believe recessive whirling disorder that causes them to dance uncontrollably. Use the pedigree to answer the following questions.

10. Explain:
How is #1 related to #3?
#1 is #3’s father

11. Explain:
How many children did #8 have? 3

12. Explain:
How many individuals in the whole pedigree have the whirling disorder? 20

13. Explain:
If #12 and #11 had children what percentage would have the whirling disorder? How do you know?
100%. Both #12 and #11 have the disorder

14. Elaborate
When organisms ___________, traits are passed from parent to offspring.
reproduce

15. elaborate
These traits are carried on _____________ made of DNA, the genetic material found in a cell’s nucleus.
chromosomes

16. elaborate
DNA
_______ provides instructions for how to produce the traits of an organism.
The part of the DNA where the instructions for a specific trait are located are known as _________.
genes

17. elaborate
You inherited genes and the traits they carry from your _______, but you don’t look exactly like either parent because you received only some genes from each parent.
These genes combined in a new way during the fertilization process of ____________ reproduction.
parents
sexual

18. elaborate
Special cells, called _________ and _________ cells, are used in sexual reproduction.
These cells form by a type of cell division called meiosis.
egg
sperm

19. elaborate
meiosis
Cells formed through _________ have only half the number of chromosomes, or genetic material, of the parent cell.
For example, humans have 46 chromosomes each, but sperm and egg cells have _________ chromosomes each. 23

20. elaborate
For reproduction to occur, the sperm and egg must join together in a process called ___________.
Once fertilized, the egg has a complete set of genetic material and will have some ___________ from each parent.
fertilization
traits

21. elaborate Not all organisms reproduce sexually.
_________ reproduction occurs when cells are formed by normal cell division known as mitosis.
Asexual

22. elaborate
mitosis
During _________ an exact copy of the DNA is made, so the resulting cells will be ______________ copies of the original with exactly the same number of chromosomes as the ____________ cell.
identical
original

23. evaluate Go back to assessment probe Baby Mice.
What are the genotypes of the parents to result in these seven baby mice? (B=black fur and b=white fur)
Father is Bb=heterozygous
Mother is bb=homozygous recessive