Transcript Genetics Vocab Introduction 2017

Mind Stretcher 2-16-17
1. Complete the other half of this
DNA sequence…make sure to copy
this half below too!
CCATGTTA
GGTACAAT
2. What is the shape of DNA?
3/25/2017
Double helix
1
Genetics
Vocabulary
Vocabulary Review
• trait
-A physical characteristic.
• heredity
-The passing of traits from
parents to offspring.
• genetics
- The scientific study of
heredity.
3/25/2017
Free template from www.brainybetty.com
3
Which of the following is
an example of a trait?
A.) Bb
B.) Talking loud
C.) Brown eyes
D.) Tying shoes
• Genes are the factors that control
Traits.
• Alleles are the different forms of
Genes.
• Individual Alleles control the
inheritance of Traits.
• An offspring receives one allele
from each parent.
3/25/2017
Free template from www.brainybetty.com
5
What is the term for
factors that control
traits?
A.) Genes
B.) Purebreds
C.) Recessives
D.) Parents
Which term refers to
physical characteristics
that are studied in
genetics?
A.) Traits
B.) Offspring
C.) Generations
D.) Hybrids
DOMINANT & recessive:
• A dominant allele is one whose
trait always shows up in an
organism when the allele is
present.
- capital letter (AA, Aa)
• A recessive allele is covered up
when the dominant allele is
present.
- lower case letter (aa)
3/25/2017
Free template from www.brainybetty.com
8
Let’s Practice• R is the dominant allele for a one
eyed monster.
• r is the recessive allele for a
monster with two eyes.
R = one eyed monster
r = two eyed monster
3/25/2017
9
Phenotype
• Phenotype is an organisms
physical appearance or its visible
traits.
• Example: a pea plant stem height
can be short or tall.
3/25/2017
Free template from www.brainybetty.com
10
Genotype
• Genotype is an organisms genetic
makeup, or allele combination.
• Example: TT, Tt, tt
3/25/2017
Free template from www.brainybetty.com
11
Monster Genetics
• Parent’s Genotype = Rr
• How many eyes will our monster have?
3/25/2017
12
Monster Genetics
• Parent’s Genotype = RR
• How many eyes will our monster have?
3/25/2017
13
Monster Genetics
• Parent’s Genotype = rr
• How many eyes will our monster have?
3/25/2017
14
What does the notation
TT mean to geneticists?
A.) Two dominant alleles
B.) Two recessive alleles
C.) No dominant alleles
D.) One dominant and one recessive
allele
Describing genotypes
• Homozygous (or Purebred) is
used to describe an organism that
has two identical alleles for a trait.
- Example: TT and tt
• Heterozygous (or Hybrid) is
used to describe an organism with
two different alleles.
- Example: Tt
3/25/2017
Free template from www.brainybetty.com
16
Pick the answer that best
describes "Aa".
A.) Homozygous
B.) Heterozygous
Punnett Squares
• A punnett square is a chart that
shows all possible combinations of
alleles that can result from a
genetic cross.
3/25/2017
Free template from www.brainybetty.com
18
Punnett Example
• Yellow is dominant over Green.
• What is the probability that the
offspring will be yellow?
100%
3/25/2017
Free template from www.brainybetty.com
19
Punnett Problems
• In purple people eaters, one-horn
is dominant and no horns is
recessive.
• Draw a Punnett Square showing
the cross of a purple people eater
that is hybrid for horns, with a
purple people eater that does not
have horns.
3/25/2017
Free template from www.brainybetty.com
20
Answer
• Hybrids have two different alleles
for one trait.
• Hh is the hybrid in the example.
• No horns would have to be hh
because it is a recessive allele.
3/25/2017
Free template from www.brainybetty.com
21
Probability
• The mathematical chance or
likelihood that an event will occur.
Remember:
Each box on Punnett square
represents 25% of the whole
(100%)
3/25/2017
Free template from www.brainybetty.com
22
Stop Here &
Complete back of sheet
3/25/2017
Free template from www.brainybetty.com
23
Codominance
• Some alleles are neither dominant
or recessive.
• Codominance is when alleles are
neither dominant or recessive,
both alleles are expressed in the
offspring.
3/25/2017
24
What will Happen?
• You have two flowers, a white and
a red, that are crossed.
• The flowers are codominant.
• What color will their offspring be?
3/25/2017
25
Incomplete Dominance
• When BOTH alleles have some
degree of influence.
*Analogy- It’s like mixing blue and
red paint colors…the result would
make PURPLE paint.
3/25/2017
26
What will Happen?
• You have two flowers, a white and
a red, that are crossed.
• The flowers display incomplete
dominance.
• What color will their offspring be?
3/25/2017
27
Punnett Problems
• In Bears the dominant allele for
brown fur is R, black fur is
recessive.
• The female bear is Rr and the
male bear is rr.
3/25/2017
Free template from www.brainybetty.com
28
What are the four possible
phenotypes for the cubs?
A.) RR, Rr
B.) Rr, rr
C.) 2 brown, 2 black
D.) 3 brown, 1 black
What is the probability
that the cub will have
black fur?
A.) 50%
B.) 25%
C.) 75%
D.) 100%
What do you call one set
of instructions for an
inherited trait?
A.) allele
B.) phenotype
C.) albinism
D.) genes
Two forms of a gene, one
from each parent, are
called
A.) alleles.
B.) phenotypes.
C.) albinism.
D.) genes.
What is a plant that has
two dominant genes or
two recessive genes
called?
A.) organism
B.) genotype
C.) homozygous
D.) heterozygous
The allele for freckles, F, is dominant
among humans. If a woman with
freckles (FF) and a man without
freckles (ff) have children, what are
the possible genotypes of the
children?
A.) Ff
B.) FF, Ff, ff
C.) Ff, ff
D.) ff
Part of a mouse’s tail is cut off as
the mouse escapes from a cat. The
mouse later reproduces. Which
explanation best describes why the
mouse’s offspring have long tails?
A.) Long tails are a dominant trait.
B.) Short tails do not appear in the first
generation or the second generation.
C.) Cutting the tail of the mouse
changed its genes.
D.) Cutting the tail of the mouse did
not change its genes.
What is the genotype of the offspring
represented in the upper left-hand
box of the Punnett square?
A.) RR
C.) rr
B.) Rr
D.) rrr
What is the ratio of Rr
(purple-flowered plants) to rr
(white-flowered plants) in
the offspring?
A.) 1:3
B.) 2:2
C.) 3:1
D.) 4:0
Green seed color (G) is dominant
to yellow seed color (g). If two
heterozygous parents are crossed,
what will be the resulting
genotypes of the offspring?
A.) GG, Gg, gg
B.) Gg, gg
C.) GG, Gg
D.) gg, GG
Justify Your Answer:
Green seed color (G) is dominant
to yellow seed color (g). If two
heterozygous parents are crossed,
what will be the resulting
genotypes of the offspring?
What is the probability of getting a
green seed color?
What is the probability of getting a
yellow seed color?