Download BIO114H - willisworldbio

HUMAN HEREDITY
OBJECTIVES: 14.1
Identify the types of human chromosomes in a
karyotype.
Explain how sex is determined.
Explain how pedigrees are used to study human
traits.
Describe examples of the inheritance of human traits.
Explain how small changes in DNA cause genetic
disorders.
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Cell biologist analyze the ___________ by
taking photographs of cells in _____.
A picture of chromosomes arranged in this way
is known as a __________.
A _____
karyotype has
__ pairs of
chromosomes
____
_____
2
These karyotypes are the result of a ______
sperm, carrying 23 chromosomes, _______ a
haploid egg, also carrying 23 chromosomes.
The diploid ______, or fertilized egg, contains
the full compliment of ___ chromosomes (23
pairs).
Two of the 46 are known as ___ chromosomes,
because they determine and individual’ sex.
_____ have two copies of a large X
chromosome.
____ have one X and one small Y chromosome.
3
Punnet square
Males and females are born in a roughly 50:50
ratio because of the way in which sex cells
segregate during ________.
4
All human eggs (___) cells carry a single X
chromosome (23,X).
Half of all sperm cells carry an __ chromosome
(23,X) and half carry a _chromosome (23,Y).
This ensures that about half of the zygotes will be
46,XX and half will be 46, XY.
5
A _______ chart shows the relationship within a
family.
It shows how the _____ is transmitted through the
generations.
6
The human _______ contains tens of thousands
of genes.
The _____ sequences on these genes carry
information for specifying many __________,
from the color of your eyes to the detailed
structures of proteins within your cells.
7
________ blood comes in a variety of genetically
determined blood groups.
A number of genes are responsible for human
blood groups, but the best known are the ___
blood groups and the __ blood groups.
The Rh is determined by a single gene with two
alleles- _______ or _______.
The positive allele is ________.
Individuals with two negative _____ are Rh
negative.
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There are three alleles for this gene __, __, and __.
IA and IB are ___________.
These allele produce molecules known as ______
on the surface of the RBC.
If you have IA and I B you produce both A and B
antigens, making you blood type __.
The i allele is ________.
IAIA and IAi produce only A antigen, making the
blood type A.
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If you have IBIB or IBi are type B.
If you are _________ for the i allele (ii) you
produce __ antigens and have the blood type O.
When referring to blood groups, usually both
groups are mentioned.
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One of the first genetic disorders to be
understood is ________________ (PKU).
Phenylalanine is an ____ acid found in ____ and
other foods, which can build up in the first years
of life of a child and cause severe __________.
Newborns can be tested for ____ and be placed
on low-phenylalanine diet, that prevents most
defects.
___-_____ disease is another disease caused by
_________ alleles.
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Disorders in humans
______
_________
________
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__________
___________
___________________
In both cystic fibrosis and sickle cell disease, a
small change in the DNA of ______ gene affect
the structure of a protein, causing a serious genetic
disorder.
CF is caused by a recessive gene on chromosome
__.
It is caused by a _______ of 3 base pairs in the
middle of a sequence for a protein.
Sickle cell disease cause RBC to be _____ and
_______.
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These RBC are more _____ than normal RBC
and tend to get stuck in the _________
(narrowest blood vessels).
Because of this the blood stops moving through
these vessels, damaging cells, ______, and
organs.
It produces physical weakness and damage to the
brain, heart, and _______ (it can be fatal).
Sickle cell occurs when the amino acid _____ is
substituted for glutamic acid.
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People who are _________ for the sickle cell
allele are generally healthy.
They are resistant to _______, which is caused by
a parasite
15
A human _____ cell contains more than ___ billion
base pairs of DNA.
Chromosome __ and __ are the smallest human
_______.
The ___ pair is called the sex genes, because they
determine the sex of the _____.
Sex-linked genes are located on the __ chromosome
(____________).
The most common is not being able to tell ___ or
______.
16
____ have only one X chromosome.
All sex-linked alleles are ______ in males, even if
they are ______.
XC
Y
XC
XCXc
XCY
Xc
XCXc
XcY
17
___________ is caused by a protein necessary for
blood clotting is missing.
A ________ allele on either of the X chromosome
of the female can cause it.
Hemophilia can be treated by injections of normal
clotting proteins, which are now produce by
________________ DNA.
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Duchenne Muscular Dystrophy is a sex-linked
disorder that results in the progressive weakening
and loss of ________ muscle.
It is caused by a defective version of the gene that
codes for muscle _______.
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Duchenne MD
20
Females have two __ chromosomes, one is
randomly turned-off and forms a dense region
around the nucleus called a ___ body.
Barr bodies are ___ found in males because they
have only one X chromosome.
21
__________ is an abnormal number of
chromosomes may find their way into _____, and
a disorder of chromosome numbers may result.
If two copies of an ________ chromosome fail to
separate during ______, and individual may be
born with three copies of a chromosome (_____).
The most common trisomy is one that involves the
__st chromosome and is known as known as ____
_______.
22
Down syndrome is
caused by nondisjuction
of the 21st chormosome
23
_____ syndrome is a sex chromosome disorder
caused by nondisjunction (___).
______ with Turner’s syndrome are _____ and
their sex organs do not ______ at puberty.
________ syndrome (47,XXY) is also cause by
nondisjunction.
The extra X interferes with _____ and usually
prevent the individual from ___________.
Klinefelter’s syndrome can also be XXXY or
XXXy.
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There have been no reported instances of babies
being born ______ and X chromosome.
This indicates that the X chromosome is vital for
_____ and ________ of the embryo.
If there is a Y chromosome present the child is
always ___.
If there is an absents of a Y chromosome the child
will be _______.
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HUMAN MOLECULAR GENETICS
OBJECTIVES: 14.3
State the goal of the Human Genome Project.
Describe how researchers are attempting to cure
genetic disorder.
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DNA fingerprinting is used to identify individuals,
because of the complexity of the human genome.
No individual is exactly like any other genetically,
except – identical twins.
The Human Genome Project is an ongoing effort
to analyze the human DNA sequence.
Gene ______ is the replacing of an absent or faulty
gene by a normal, working gene.
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