Download Unit 5: Heredity

Unit 5: Heredity
Genetics
physical
• Eye color, nose shape, and many other ___________
features are
inherited from parents.
some of the traits that are ___________
collection of traits, all inherited from its
• An organism is a ___________
__________
parents
traits from parent to
Heredity
• ___________-is
the passing of ________
offspring
Alleles
forms of a trait that a _______
gene may
• _________different ________
have
Genetics
chromosomes separates during ________
meiosis
• When a pair of ______________
different sex cells
alleles for each trait also separate into __________
one allele for each trait
sex cell has ______
• Every ______
Offspring inherit one allele for a trait from each parent
• ___________
Genetics
study of how traits are ___________
inherited
• ___________the _______
through the interactions of ________
alleles
Genetics
pea plants helped scientists understand
• Experiments with ______
human traits
________
Gregor Mendel
• _________
_______ was an Australian monk who had an interest
in ________
plants from an early age
Scientific ________
method and
• Mendel spent years carefully using the ________
traits pass from one ___________
discovered how ________
generation to the
next
probability to
• Mendel was the first to use the mathematics of ____________
explain __________
heredity
Wildcats Share
• Before Mendel scientists studying genetics often studied many
traits at one time. Mendel was the first to trace one trait
through several generations.
• Why do you think Mendel was more successful in making
discoveries using the scientific method?
Genetics
trait
• Each time Mendel studied a ________,
he crossed two plants
different expressions of the trait and found that new
with _________
plants looked like ______
one of the parents
Hybrid
different genetic
• _________offspring that received __________
information, or ________
alleles from each parent
produces the same traits
• An organism that always ___________
purebred
generation after ____________
generation is called a __________
Genetics
Cross-pollination
• In Mendel’s experiment he used a process called _____________
tall plants with purebred
to pollinate, by hand, purebred ______
________
short plants
seeds that produced _____
tall plants
• This pollination resulted in _______
Dominant
dominates another
• ___________a factor that covers up, or ___________,
form of that trait
Recessive a trait that is covered up, or dominated, by another
• __________trait and seems to __________
form of that _______
disappear
Wildcats Share
• Refer back to the activity traits activity we worked on in class.
Looking at the percentages calculated, predict if the following
traits are dominant or recessive.
Prediction
Answer
• Trait
Dimples
Rolling tongue
Dominant
Dominant
Thumbs crossed right
over left
Recessive
Earlobes attached
Recessive
Cleft Chin
Dominant
Genetics
Probability is a branch or mathematics that helps you
• ____________
predict the chance that something will _________
happen
_________
coin lands on the side you
• If you flip a coin the probability the ______
want is ___
1 out of ____
2
predictions accurate was that
• One thing that made Mendel’s ____________
he worked with _______
large numbers of plants
8 years
30,000 pea plants over ___
• Mendel studied almost ________
increased Mendel’s chances of seeing ____________
repeatable
• This ___________
patterns
Genetics
Punnett_______square a tool to predict the ____________
probability of a
• ________
different ways alleles can
certain trait in offspring that shows __________
combine
dominant alleles, and lowercase
• Uppercase letters represent __________
__________
recessive
genetic makeup of an organism
Genotype
• ____________________
appearance and behavior of
Phenotype outward physical ____________
• ___________an organism as a result of its ___________
genotype
Genetics
two alleles for every trait
• Most cells in your body have _____
Homozygous an organism with ______
two alleles that are the
• __________________
same
• Example:
TT for tall plant, tt for short plant
Heterozygous
• ______________an organism that has two _________
different alleles
for a trait
• Example: Tt hybrid plants Mendel created
Genetics
Punnett square
• When creating a _________
________ the two alleles from one
top
parent are written along the _______,
one letter per square, and
the two alleles from the other parent are written on the ______
side
allele donated by
• Each square of the grid is filled in with one _______
parent
each ________
squares
• The letters that you use to fill in each of the __________
genotypes of possible offspring that the parents
represent the ___________
could produce
Genetics
• Mendel developed the following principles through his research
DNA genes, or
even though he didn’t know anything about _______,
______________
chromosomes
alleles on chromosomes
controlled by ________
1. Traits are ___________
dominant or ___________
recessive
2. An allele’s effect is ___________
chromosomes separates during _________
meiosis
3. When a pair of ______________
separate sex cells
the different alleles for a trait move into __________
Genetics Since Mendel
• Mendel’s work was later re-tested and is was discovered that not
alleles of all organisms display ___________
complete dominance
all ________
and recession
red flowers with
• One scientist found when he crossed ______
white flowers he got _______
pink flowers
_______
Incomplete dominance
• ____________
___________- production of a phenotype that is
intermediate between the two _____________
_____________
homozygous parents
Genetics Since Mendel
• Mendel didn’t discover incomplete dominance because he
two alleles
studied traits that were controlled by ______
multiple alleles if there are more than
• A trait is controlled by __________
two alleles that control the trait.
______
three
• Traits controlled by multiple alleles result in more than _______
phenotypes of that trait.
multiple alleles
• _______
Blood type in humans is an example of __________
four phenotypes
that produce _______
Genetics Since Mendel
A
B and ____.
O
• The allele for blood type are called _____,
____,
A and ____
O is recessive to _____
B
Where ____
B allele, both
A allele and one ____
• When a person inherits one ____
AB
are expressed and the phenotype is ______
phenotype A has a genotype of _____
AA or _____
AO
• A person with ___________
phenotype B has a genotype of _____
BO
BB or _____
• A person with ___________
O has a genotype of ______
OO
• A person with phenotype ____
Genetics Since Mendel
Polygenic inheritance
group of gene pairs
• _________
__________- occurs when a _______
acts together to produce a trait
• Ex:
Height and the color of your eyes, skin, and hair
alleles produce a wide variety of
• The effects of many _______
____________
phenotypes
Environment
• _______________
also plays an important role in the
___________
expression of these traits
• Other traits controlled by phylogenic inheritance are:
Grain color in wheat and milk and egg production in
cows and chickens
Genetics Since Mendel
Genetic disorders
recessive
• Many human _________
________ are caused by __________
genes
• Such genetic disorders occur when both parents have a recessive
allele responsive for the __________
______
disorder
heterozygous they don’t show any
• Because the parents are ______________
__________
symptoms of the disorder
offspring inherits two recessive alleles it will be
• If the __________
homozygous and have symptoms of the genetic disorder
_____________
Genetics Since Mendel
• What determines the sex of an individual?
Fruit flies
• Scientist studied this question using ______
_____
one pair of ______________
chromosomes that determine
• They identified ______
the sex of organisms
XX is labeled female and a _____
XY male
• A pair of ______
egg produced by a female normally contains one ____
X
• Each ______
chromosome
X or ____
Y
• Males produce sperm that normally have either an ____
chromosome
Genetics Since Mendel
inherited conditions are linked with the ____
X and ____
Y
• Some __________
chromosomes
Sex-linked gene_____- an allele inherited on a ______
sex
• ______________
chromosome
• Ex:
Color blindness
• More common in males that females because males only have one X
chromosome, which this condition is associated with, females have two
X chromosomes, which means both must carry the allele for a female to
be color blind
Wildcats share
• https://www.youtube.com/watch?v=BD6h-wDj7bw
• While watching the video find answers to the following
questions, we will have a discussion after the video
1. Why must one X chromosome be inactivated in females?
2. What are differences between the active and inactive X
chromosomes?
3. Does the same X chromosome always win?
4. What give calico cats their different colors?
Genetics Since Mendel
pedigree is a visual tool for following a _______
trait
• A __________
through
generations of a family
completely filled shape shows that a trait is ______
seen in that
• A ____________
person
Half-colored
• ______________
shaped indicate carriers
Empty shapes represent organisms that do not have a ______
trait
• ________
carriers
and are not __________
Genetics Since Mendel
geneticists
• Pedigrees are useful tools for _____________
recessive
• Geneticists can determine if a trait is ___________,
dominant,
Sex-linked
____________,
or has come other pattern of inheritance
probability a baby will have specific
• They can also predict the ____________
trait
Pedigrees are also important in __________
breeding plants or
• ___________
animals
Genetics Since Mendel
yield and nutritional content of
• Pedigrees are used to increase ________
___________
livestock and plant crops
• Also used by __________
breeders of show animals, like dogs, to breed for
possible desirable ____________
traits
physical
health
• Issues concerning __________
are also considered when
_____________
researching pedigrees
Advances in Genetics
gene has become a _____________
common
• The term _______
word in our
society
hereditary
change the
• The principles of _____________
are being used to ________
world
Genetic engineering
• _________
__________- scientists experimenting with
biological and chemical methods to change the
___________
arrangement
______________
of a gene’s DNA to improve _______
crop
production, produce large volumes of __________,
medicine and change
how cells perform their normal functions.
Advances in Genetics
genetic
recombinant DNA is one method of _________
• Making _____________
engineering
DNA is made by __________
inserting a useful segment of DNA
• This _______
from one ___________
organism into a ___________
bacterium
insulin to treat Type I
• This method can be used to make ________
diabetes, and chemical to treat __________
and other diseases
cancer
Advances in Genetics
Gene therapy
• _______
_________ is another kind of genetic engineering
virus
normal allele being placed in a _______
• This process involved a _________
allele when it infects its _________
target
• The virus then delivers the ________
cell
defective one
normal
• The __________
allele then replaces the __________
Cystic fibrosis
• Research is being done using this method to treat _______
________,
some kinds of _________,
and other __________
genetic disorders
cancer
Advances in Genetics
selective breeding
• For thousands of years people have used __________
food and clothing
to improve the plants they use for _______
Genetic engineering
• _________
__________ along with selective breeding are being
used to make ______________
improvements to food
desired trait can now be
• Genes from a plant that produce a _________
different plant
inserted into a __________
research
• Developments are still being made in this field and __________
impacts
is still being done to determine the __________