HEREDITY
1.
What is heredity?
2.
What is genetics?
3.
What are traits? Give an example
4.
GAMETES = are sex cells ( sperm & egg)
5.
After fertilization occurs , the resulting cell is called a ZYGOTE
6.
Who was the scientist responsible for the idea of heredity?
7.
What did this scientist use to conduct his experiment for heredity?
8.
What a PHENOTYPE? Give an example
9.
What is a GENOTYPE? Give an example
10.
There are two different types of expression for traits (GENOTYPE)
a. dominant traits ( always wins) = represented by__________ letters
b. recessive traits ( always looses, unless it is homozygous recessive) = represented by
________case letters
11.
What is homozygous?
Example: If I am homozygous dominant for green eyes (G), then my genotype would
be_______
If I am homozygous recessive for red hair (r), then my genotype would be ______
12.
What is heterozygous?
Example: If I am heterozygous for big eyes (E), then my genotype would be _____
13.
Complete the punnet square for the following
a. IF one parent is heterozygous for orange hair and the other is homozygous dominant
for green hair. Orange hair (O), green hair (o). What are the genotypes for the
offspring?
How many kids have orange hair: _____?
How many kids have green hair______?
What % is heterozygous: _____?
What % are homozygous dominant: _____
What % are homozygous recessive: _____
b. If both parents are heterozygous for height. Tall (T), short (t). What are the
genotypes for the offspring?
How many kids are tall: _____?
How many kids are short______?
What % is heterozygous: _____?
What % are homozygous dominant: _____
What % are homozygous recessive: _____
c. If one parent is homozygous dominant for black skin and the other is homozygous
recessive for light skin. dark skin (D), light skin (d). What are the genotypes of the
offspring
How many kids have dark skin: _____?
How many kids have light skin______?
What % is heterozygous: _____?
What % are homozygous dominant: _____
What % are homozygous recessive: _____
d.. If one parent is homozygous recessive for long hair and the other is heterozygous for
short hair, long hair (r), short hair (R). What are the genotypes and phenotypes of the
offspring?
How many kids have long hair: _____?
How many kids have short hair______?
What % is heterozygous: _____?
What % are homozygous dominant: _____
What % are homozygous recessive: _____
14.
What are homologous chromosomes?
15.
Draw a picture of a homologous chromosome. Make sure you include chromosomes that
are not homologous with each other
16. What does the law of segregation state?
17. What does the law of independent assortment state?
18. What does the rule of dominance state?
19. What does the rule of factor state?
20. What is the difference between a dihybrid cross and a monohybrid cross? Complete the
dyhybrid cross
Round and yellow (RY)
Round and green (Ry)
Wrinkled and yellow (rY)
Wrinkled and green (ry)
21. What is the difference between diploid and haploid number of chromosomes. Complete
the table
Organisms
Fruit fly
Body Cells (2n)
8
Garden Pea
Corn
7
20
Tomato
Human
12
46
Dog
Apple
Gametes (n)
39
34
Mitosis & Meiosis
Mitosis
Meiosis

cell division

sexual reproduction

has 5 stages

has 2 phases: meiosis I & meiosis II
- interphase = chromosomes duplicate, cells

has 9 stages
grow & develop
meiosis I
- prophase = chromatids condense to form
visible chromosomes
- prophase I = homologous chromosomes pair
up. Genes cross over .Spindle fibers form
- metaphase = chromosomes move to the
middle of the cell
- metaphase I = homologous chromosomes
move to the middle of the cell, by spindle fibers
- anaphase = Centromeres split. Sister
- anaphase I = homologous chromosomes move
chromatids move to the opposite side of the
to the opposite sides of the cell. centromeres do not
cell
split
- telophase= 2 daughter cells form
* cytokenisis = splits the daughter cells in
half
- telophase I = 2 daughter cells are formed,
with 1 chromosome a piece. Spindle fibers break
down . Homologous chromosomes uncoil

results in 2 identical daughter cells

each daughter cell has DIPILOID # (2n) of
-
chromosomes
- metaphase II = chromosomes move to the
Example: humans have 46 chromosomes
middle of the cell

meiosis II
prophase II = visible chromosomes
- anaphase II = Sister chromatids move to
the opposite side of the cell
- telophase II = 4 daughter cells are
formed
* cytokenisis = cytoplasm splits the
daughter cells in half

results in 4 different daughter cells

each daughter cell has HAPLOID # (n) of
chromosomes

Example: sperm & egg cells have 23
chromosomes
Draw the phases for each process ( Mitosis and Meiosis)
22.
What is genetic recombination?
23.
What is nondisjunciton?
Nondisjunciton results in chromosomal mutations ( mutations in your chromosomes)
24.
25.
What are chromosomal mutations?
26.
There are 4 types of chromosomal mutations
Name
Description
part of a chromosome that breaks off
and reattaches backwards
part of a chromosome is left out
part of one chromosome breaks off and
is added to a different chromosome
Part of a chromosome breaks off and
attaches to its sister chromatid.
Results in duplicate (copy) of the same
genes
Word bank:
insertion
translocation
deletion
inversion
27.
What is a mutation?
28.
. What is a mutagen?
Example
There are two main type of changes that can occur if there is an alteration in an amino
acid of a protein chain. They are:
a. POINT MUTATION =
Examlpe: each 3 letter word represents 1 amino acid. Remember 3 NITORGENOUS BASES
codes for 1 AMINO ACID
THE DOG BIT THE CAT
THE DOG BIT THE CAR
T was changed to R
B. FRAMESHIFT MUTATION =
Example:
THE DOG BIT THE CAT: original DNA stand
THE DOB ITT HEC AT: delete the base G
THE DOG BIT THH ECA T: add the base H