Transcript Genetics Reviewx - Glen Ellyn School District 41

Genetics Review!
Question 1
What is the genetic
material of all organisms
made up of 2 twisted
strands of sugarphosphate and nitrogen
bases?
1
DNA
Question 2
What is a section of
DNA located on a
chromosome /controls
traits?
2
Gene
Question 3
What is the
passing of traits
from parents to
offspring?
3
Heredity
Question 4
Who is the father of
genetics?
4
Mendel
Question 5
An organism
receives how many
genes for each trait
and from whom?
5
•2
• One from each parent
Question 6
What is the gene that if
present, its trait will
always show up in the
individual?
(The allele is represented by
a capital letter.)
6
•Dominant
•RR or Rr
Question 7
What is the weaker gene
that may be hidden and
not show up in the trait of
an individual unless there
are two of them?
(The allele is represented by a
lowercase letter.)
7
•Recessive
•rr
Question 8
If an organism has 2
dominant or 2
recessive genes it is
said to be what?
8
Pure bred or Pure
BB
bb
Question 9
If an organism
has 2 different
genes it is said to
be what?
9
A Hybrid (Bb)
• Think of a hybrid car- runs on 2
different sources of energy
Another hybrid
Question 10
If an organism has 2
dominant or 2
recessive alleles it is
said to be what?
10
Homozygous
Question 11
Which is homozygous
dominant, which is
homozygous recessive,
and heterozygous?
RR
Rr
rr
11
Homozygous dominant- RR
Homozygous recessive- rr
Heterozygous- Rr
Question 12
If an organism has 2
different alleles it is
said to be what?
12
Heterozygous
Question 13
Draw a Punnett Square
- Make mom Pure TALL
- Make dad SHORT
Genotypes and Phenotypes
of kids
13
t
T
T
Tt Tt
Tt Tt
t
Genotype- Tt
Phenotype- 100% tall
Question 14
Using the letter “H”:
Draw a Punnett Square
Cross two HYBRID parents
14
H
HH
h
Hh
Hh
hh
H
h
Question 15
Looking at your Punnett Square:
What is the probability of having
offspring that are purebred
recessive?
15
1:4 or 25%
Question 16
What is the word used that means:
a single letter that is written that
represents a dominant or recessive
trait passed from one parent
16
Allele
Question 17
Write a genotype that says
the offspring is purebred
recessive
17
aa bb cc dd
ee ff gg
Question 18
Write a genotype that
says the offspring is
purebred dominant
18
AA BB CC DD
EE FF GG
Question 19
Write a genotype
that says the
offspring is a hybrid
19
Aa Dd Gg Nn Rr
Question 20
Set up and solve a punnett square from this information:
Brown hair is dominant over blonde hair
Brad and Angelina are expecting children very soon.
Brad is pure for brown hair. Surprisingly, Angelina is
also pure, but for blonde hair.
How many children will be homozygous dominant?
Homozygous recessive? Heterozygous?
20
B
Bb
B
Bb
Bb
Bb
b
b
Homozygous Dominant: none
Homozygous Recessive: none
Heterozygous: 4:4 or 100%
Question 21
It is a word on the word wall…
Can be passed down by one of your
parents
It is the allele that covers up the
weaker allele
Ex: tongue roller, widow’s peak
23
dominant
Question 24
Word on the word wall:
Each parent provides one
Comes in pairs
Pair can be dominant, recessive, or
both
Ex: a or A
allele
Question 25
Word on word wall:
Illustrates probability
Genetic cross
Shows allele combinations
Punnett square
Question 26
Word on word wall:
Branch of science
Study of heredity
Explains how traits are passed down from parents
Genetics
Question 27
Word on word wall:
Found in every cell
DNA is located here
23 pairs of these
Chromosome
What is one of several
possible forms of a gene?
allele
What is the physical
appearance of an individual?
phenotype
When the genotype consists of a
dominant and a recessive allele, the
phenotype will be like what allele?
Answer: dominant
On average, how many
offspring of heterozygous
parents will be homozygous
recessive?
ANSWER: 25%
How many
chromosomes are in
human body cells?
ANSWER: 46 OR 23 PAIRS
If 2 organisms have the same
phenotype, does that mean
they have the same genotype?
ANSWER: NO
In peas, yellow color is dominant to
green. What will the colors of the
offspring be between a
homozygous yellow and a
homozygous green?
What would their
genotypes/phenotypes be?
Yy
PHENOTYPE: THEY WILL ALL BE YELLOW
Could two brown-eyed parents have a
blue-eyed child? Explain by creating a
punnett square!
ANSWER: YES, BECAUSE THEY WOULD
BOTH HAVE TO BE HETEROZYGOUS
(THEY BOTH HAVE TO CARRY A
RECESSIVE ALLELE FOR BLUE EYES)
What are factors
that control traits?
ANSWER: GENES
What is the gene makeup of a
trait?
GENOTYPE
A blue eyed man both of whose
parents were brown eyed, Marries a
brown eyed woman whose father was
blue eyed and whose mother was
brown eyed. The man and this woman
have a blue eyed child. What are the
genotypes of all individuals listed.
Answer
• Dad’s dad- Bb
• Dad’s mom- Bb
• Dad-bb
• Child- bb
Mom’s dad- bb
Mom’s mom- Bb or BB
Mom- Bb