Name ______________________________ Class ___________________ Date __________________
Meiosis and Mendel
Study Guide A
Answer Key
SECTION 1. CHROMOSOMES AND
MEIOSIS
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
SECTION 3. MENDEL AND HEREDITY
1.
2.
3.
4.
5.
6.
7.
8.
somatic/body cells; germ cells/gametes
reproductive
46
mother
father
autosomes
X
Y
female
Y
fuse
Germ
haploid
sex chromosome
Mitosis
Meiosis
a; b; e
9.
10.
11.
12.
inheritance
Mendel
traits
b
c
a
quickly; mate
dominant; both dominant and recessive
phenotypes.
genes
i, two copies; ii, one copy
genes
genetics
SECTION 4. TRAITS, GENES, AND
ALLELES
1.
2.
3.
4.
5.
SECTION 2. PROCESS OF MEIOSIS
1. sister chromatid
2. homologous
3. Refer to Figure 2.3 for visual answers.
prophase I
4. metaphase I
5. anaphase I
6. telophase I
7. prophase II
8. metaphase II
9. anaphase II
10. telophase II
11. anaphase I should be circled; anaphase II
should be boxed.
12. Sperm cell :DNA; Egg: DNA, organelles,
molecular building blocks
13. female
14. Refer to Figure 2.4 for visual answers.
15. birth or formation
16. meiosis; broken down
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
gene; protein
gene; locus
homozygous; heterozygous
genes; alleles
Images should be similar to the Visual
Vocab on the first page of Section 4.
Students will label Gene A, Gene A,
Gene B, and Gene b.
Genotype: b and c; Phenotype: a and d
dominant; recessive
environment
TT
recessive
dominant
Tt
dominant
allele
heterozygous; recessive
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide A
i
Meiosis and Mendel
Name ______________________________ Class ___________________ Date __________________
Study Guide A continued
SECTION 5. TRAITS AND
PROBABILITY
SECTION 6. MEIOSIS AND GENETIC
VARIATION
1. The “A a” pairs located above the grid and
to the left of the grid should be circled.
2. AA, Aa, and aa
3. meiosis; homologous
4. genotype; phenotype
5. 1:2:1
6. 3:1
7. c
8. AB; Ab
9. 9:3:3:1
10. average; exact
11. multiply
12. recessive; unknown
13. allele pairs
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
meiosis; random
new combinations of alleles
advantage; increases
duplicated
Refer to Figure 6.2 for visual answers.
Box 1: Each cell should contain one large
duplicated chromosome and one small
duplicated chromosome. One sister
chromatid on each chromosome should
appear to have undergone crossing over.
Box 2: Each cell should contain one large
chromosome and one small chromosome.
The exact combination of chromosomes will
depend on how the students divided the
chromosomes.
Yes; a
Yes; c
No; b
crossing over
genetic linkage
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology
Study Guide A
ii
Meiosis and Mendel
Name ______________________________ Class ___________________ Date __________________
Chromosomes and Meiosis
Study Guide
MAIN IDEA: You have body cells and gametes.
Fill in the blank with the word or phrase that best completes the sentence.
1. The two major groups of cell types in the human body are called
______________ and ______________.
2. The gametes are located in the _____________ organs.
3. The number of chromosomes in a typical human body cell is _______.
MAIN IDEA: Your cells have autosomes and sex chromosomes.
Fill in the Concept Map below to summarize what you know about chromosomes.
46 chromosomes in
human body cells
include
sex chromosomes
include
half
come
from
include
4.
5.
6.
include
consist of
7.
8.
22 homologous pairs
Circle the word or phrase that best completes the statement.
9. A person with two X chromosomes is female / male.
10. The X / Y chromosome carries the fewest number of genes.
Name ______________________________ Class ___________________ Date __________________
MAIN IDEA: Body cells are diploid; gametes are haploid.
Circle the word or phrase that best completes the sentence.
11. What happens to the nuclei of the egg and sperm during fertilization?
12. What type of cells are haploid?
13. What is the haploid chromosome number in humans?
14. How many autosomes are present in each human gamete? How many sex
chromosomes?
Read the descriptions in the table below and then decide which column should be
labeled Mitosis and which column should be labeled Meiosis.
15. Mitosis
16. Meiosis
Makes diploid cells.
Makes
Makes
cells.
Makes
Happens
organism’s life.
an
Happens at
an organism’s life.
Involved in
reproduction.
Involved in s
cells.
cells.
in
reproduction.
17. What are homologous chromosomes?
18. Circle all of the following statements that are true for
homologous chromosomes.
a. One is from the mother and one is from the father.
b. They are a pair of chromosomes.
c. They are fertilized gametes.
d. They have the same genes, but they differ in length and appearance.
e. They have the same genes, length, and overall appearance.
Name ______________________________ Class ___________________ Date __________________
Process of Meiosis
Study Guide
KEY CONCEPT
During meiosis, diploid cells undergo two cell divisions that result in
haploid cells.
MAIN IDEA: Cells go through two rounds of division in meiosis.
Circle the word or phrase that best completes the statement.
1. After a chromosome is replicated, each half is called a
.
2. Two chromosomes that are very similar and carry the same genes are called
.
In the space below, sketch the phases of meiosis I and II and write the name of
each phase below it. Use Figure 2.3 to help you.
Meiosis I
4.
3.
6.
5.
Meiosis II
7.
8.
9.
10.
11. In the diagram above, circle the phase in which homologous chromosomes separate,
and put a box around the phase in which sister chromatids separate.
Name ______________________________ Class ___________________ Date __________________
MAIN IDEA: Haploid cells develop into mature gametes.
12. The sperm cell and the egg both contribute to an embryo. Place a check
mark in the appropriate boxes below to indicate what each gamete contributes
to the embryo.
Sperm cell
Egg
DNA
Organelles
Molecular building blocks
13. Where are polar bodies made, in the male or in the female?
___________________
14. Complete the diagram of gametogenesis in the boxes below. Use Figure 2.4 to
help you.
Sperm Formation
Egg Formation
Fill in the blank with the word or phrase that best completes the sentence.
15. Genesis comes from a Greek word that means “to be born.” Therefore,
gametogenesis is the _____________ of gametes.
16. Polar bodies are cells produced by ______________ in the female body.
They contain little more than DNA and are eventually _______________.