Genetics: The Science of Heredity - PowerPoint PPT Presentation

Loading...

PPT – Genetics: The Science of Heredity PowerPoint presentation | free to download - id: 6e6ec2-YWFjZ



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Genetics: The Science of Heredity

Description:

Genetics: The Science of Heredity Chapter 3 – PowerPoint PPT presentation

Number of Views:34
Avg rating:3.0/5.0
Slides: 87
Provided by: DUAN99
Learn more at: http://moodle2.wythe.k12.va.us
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Genetics: The Science of Heredity


1
Genetics The Science of Heredity
  • Chapter 3

2
VA Standards of Learning addressed
  • LS.1 The student will plan and conduct
    investigations in which
  • a) data are organized into tables showing
    repeated trials and means
  • d) sources of experimental error are identified
  • e) dependent variables, independent variables,
    and constants are identified
  • g) continuous line graphs are constructed,
    interpreted, and used to make predictions and
  • i) an understanding of the nature of science is
    developed and reinforced.
  • LS.2 The student will investigate and understand
    that all living things are composed of cells. Key
    concepts include
  • d) cell division (mitosis and meiosis).
  • LS.3 The student will investigate and understand
    that living things show patterns of cellular
    organization. Key concepts include
  • b) life functions and processes of cells,
    tissues, organs, and systems (respiration,
    removal of wastes, growth, reproduction,
    digestion, and cellular transport).
  • LS.13 The student will investigate and understand
    that organisms reproduce and transmit genetic
    information to new generations. Key concepts
    include
  • a) the role of DNA
  • b) the function of genes and chromosomes
  • c) genotypes and phenotypes
  • d) factors affecting the expression of traits
  • e) characteristics that can and cannot be
    inherited
  • g) historical contributions and significance of
    discoveries related to genetics.
  • LS.14 The student will investigate and understand
    that organisms change over time. Key concepts
    include
  • a) the relationships of mutation, adaptation,
    natural selection, and extinction

3
Chapter 3, Section 1 Mendels Work
  • After completing the lesson, students will be
    able to
  • Describe Mendels genetics experiments
  • Identify the factors that control the inheritance
    of traits in organisms
  • Explain how genetics use symbols to represent
    allels.

4
Who was Mendel?
  • Gregor Mendel was a young _________ from a
    monastery in Central Europe in the mid-1800s
  • Studied math and science at the University of
    Vienna
  • Tended the monasterys garden and became curious
    about why some of the plants had different
    characteristics, or _______________.
  • Mendel experimented with thousands of pea plants
    to understand the process of ________, the
    passing of ______________ from parents to
    offspring.
  • His work formed the foundation of _________, the
    scientific study of _______________.

5
Who was Mendel?
  • Gregor Mendel was a young priest from a monastery
    in Central Europe in the mid-1800s
  • Studied math and science at the University of
    Vienna
  • Tended the monasterys garden and became curious
    about why some of the plants had different
    characteristics, or traits.
  • Mendel experimented with thousands of pea plants
    to understand the process of heredity, the
    passing of traits from parents to offspring.
  • His work formed the foundation of genetics, the
    scientific study of heredity.

6
Why study PEAS????
  • Many ______________ that exist in only
    ____________ forms
  • Pea plant stems are either ___________ or
    _________________
  • Garden peas produce a large number of
    __________________ in one generation making it
    easy to collect large amounts of _____________ to
    analyze

7
Why study PEAS????
  • Many traits that exist in only two forms
  • Pea plant stems are either tall or short
  • Garden peas produce a large number of offspring
    in one generation making it easy to collect large
    amounts of data to analyze

8
More on Peas
  • In nature, pea plants are usually
    __________________. This means that pollen from
    one flower lands on the pistil of the
    ____________ flower.
  • A ________________ plant is one that always
    produces offspring with the same form of a trait
    as the parent.

Stamens
Pistil
9
More on Peas
  • In nature, pea plants are usually
    self-pollinating. This means that pollen from
    one flower lands on the pistil of the same
    flower.
  • A purebred plant is one that always produces
    offspring with the same form of a trait as the
    parent.

Stamens
Pistil
10
What are they?
  • The __________ produces ______ sex cells, or
    eggs, while the _____________ produce pollen,
    which contains the __________ sex cells.

Stamens
Pistil
11
What are they?
  • The pistil produces female sex cells, or eggs,
    while the stamens produce pollen, which contains
    the male sex cells.

Stamens
Pistil
12
(No Transcript)
13
Self-Pollination
14
__________
____________
_____________
When Mendel crossed __________________tall and
short plants, all the offspring in the F1
Generation were tall. In the F2 Generation,
three fourths of the plants were tall, while one
fourth were short.
15
P Generation
F1 Generation
F2 Generation
When Mendel crossed purebred tall and short
plants, all the offspring in the F1 Generation
were tall. In the F2 Generation, three fourths
of the plants were tall, while one fourth were
short.
16
Other Traits
  • Mendel studied seven traits in garden peas seed
    shape, _________ __________, seed coat color,
    ________ ________, pod color, _________
    _________, and stem height.
  • The results in each experiment were ___________
    to those observed with stem height.

17
Other Traits
  • Mendel studied seven traits in garden peas seed
    shape, seed color, seed coat color, pod shape,
    pod color, flower position, and stem height.
  • The results in each experiment were similar to
    those observed with stem height.

18
Book Work
  • Turn to page 89 in your text book.
  • Complete the chart on the Genetics of Pea Plants
    handout.
  • When it is complete - place it in your binder.

19
Dominant and Recessive Alleles
  • Mendel reasoned that _______________ factors must
    control the _____________ of traits in peas.
    The ___________ that control in each trait exist
    in __________. One factor from the female parent
    and one factor from the male parent.
  • Mendel went on to reason that one factor in a
    pair can __________, or _________, the other
    factor. Tallness ____________ the shortness
    factor.

20
Dominant and Recessive Alleles
  • Mendel reasoned that individual factors must
    control the inheritance of traits in peas. The
    factors that control in each trait exist in
    pairs. One factor from the female parent and one
    factor from the male parent.
  • Mendel went on to reason that one factor in a
    pair can mask, or hide, the other factor.
    Tallness masked the shortness factor.

21
Alleles Contd
  • Scientists call the factors that control traits
    _________. They call the different forms of a
    gene ____________.
  • Individual _____________ control the inheritance
    of traits. Some alleles are __________, while
    other alleles are ___________.
  • ____________ allele is one whose trait always
    shows up in the organism when the allele is
    present. A _____________ allele, on the other
    hand, is masked or covered up, whenever the
    dominant allele is present.

22
Alleles Contd
  • Scientists call the factors that control traits
    genes. They call the different forms of a gene
    alleles.
  • Individual alleles control the inheritance of
    traits. Some alleles are dominant, while other
    alleles are recessive.
  • Dominant allele is one whose trait always shows
    up in the organism when the allele is present. A
    recessive allele, on the other hand, is masked or
    covered up, whenever the dominant allele is
    present.

23
Understanding Mendels Crosses
  • Understanding Mendels Crosses Definition
  • Hybrid An organism that has two different
    alleles for a trait

24
Mendel
  • Today known as the ________ ___ _____
  • However, his work had been forgotten for ____
    _________ before being rediscovered in _________
    by three different scientists who recognized his
    the importance of his work.

25
Mendel
  • Today known as the Father of Genetics
  • However, his work had been forgotten for 34 years
    before being rediscovered in 1900 by three
    different scientists who recognized his the
    importance of his work.

26
Chapter 3 Section 2 Probability and Genetics
  • After completing the lesson, students will be
    able to
  • Describe the principles of probability and how
    Mendel applied them to inheritance
  • State how geneticists use Punnett squares
  • Explain the meanings of the terms phenotype,
    genotype, homozygous, heterozygous, and
    cocominance.

27
Mini Lab Mini Lab Mini Lab What is the Chance
  • In your lab notebook
  • Suppose you were to toss a coin 20 times.
    Predicts how many times the coin would land
    heads up and how many times it would land
    tails up.
  • Now test your prediction by tossing a coin 20
    times. Record the number of times the coin lands
    heads up and the number of times it land tails
    up.
  • How did steps 1 and 2 compare?

28
________________
  • ________________ is the ___________ that a
    particular event will occur.
  • The laws of _________________ predict what is
    likely to occur, not necessarily what will occur.
    However, the more tosses you make, the closer
    your actual results will be to the results
    predicted by probability.

29
Probability
  • Probability is the likelihood that a particular
    event will occur.
  • The laws of probability predict what is likely to
    occur, not necessarily what will occur. However,
    the more tosses you make, the closer your actual
    results will be to the results predicted by
    probability.

30
__________ and Probability
  • ___________ was the first scientist to
    _______________ that the principles of
    probability can be used to predict the results of
    genetic crosses.

31
Mendel and Probability
  • Mendel was the first scientist to recognize that
    the principles of probability can be used to
    predict the results of genetic crosses.

32
_____________ Squares
  • A ____________ Square is a chart that shows all
    the possible combinations of ___________ that can
    result from a _________ _____.
  • Geneticists use _____________ Squares to show all
    the possible outcomes of a genetic cross and to
    determine the probability of a particular
    outcome.

33
Punnett Squares
  • A Punnett Square is a chart that shows all the
    possible combinations of alleles that can result
    from a genetic cross.
  • Geneticists use Punnett Squares to show all the
    possible outcomes of a genetic cross and to
    determine the probability of a particular
    outcome.

34
Punnett Square
T T
(25) Tt (25 ) Tt
(25) Tt (25) Tt
t t
35
Punnett Square
T t
(25) TT (25) Tt
(25) Tt (25) tt
T t
36
Now you try..
B B


B b
37
Now you try..
B B
BB BB
Bb Bb
B b
38
Terms
  • An organisms _________________ is its physical
    appearance, or its visible traits. (Ex. tall or
    short stems)
  • An organisms _________________ is its genetic
    makeup.

__________ ______ ______________ __________ ______ ______________
_________ _________
________ TT
Tall ________
________ tt
39
Terms
  • An organisms phenotype is its physical
    appearance, or its visible traits. (Ex. tall or
    short stems)
  • An organisms genotype is its genetic makeup.

Phenotype and Genotype Phenotype and Genotype
Phenotype Genotype
Tall TT
Tall Tt
Short tt
40
More Terms
  • An organism that has two identical alleles for a
    trait is said to be _______________.
  • An organism that has two different alleles for a
    trait is said to be _______________.
  • ______________ used the term _______________ to
    describe ______________.

Phenotype Genotype ___________ Or ___________
Tall TT ___________
Tall Tt ___________
Short tt ___________
41
More Terms
  • An organism that has two identical alleles for a
    trait is said to be homozygous.
  • An organism that has two different alleles for a
    trait is said to be heterozygous.
  • Mendel used the term hybrid to describe
    heterozygous.

Phenotype Genotype Homozygous Or Heterozygous
Tall TT Homozygous
Tall Tt Heterozygous
Short tt Homozygous
42
One More Term
  • In ___________________, the alleles are neither
    dominant nor recessive. As a result, both
    alleles are expressed in the offspring.

43
One More Term
  • In codominance, the alleles are neither dominant
    nor recessive. As a result, both alleles are
    expressed in the offspring.

44
If Erminette chickens reproduced.
45
What is this an example of?
  • _____________________

46
What is this an example of?
  • CODOMINANCE Roan Cattle are an example of
    codominance

47
Chapter 3, Section 3 The Cell and Inheritance
  • After completing the lesson, students will be
    able to
  • Describe chromosomes and their role in
    inheritance
  • Identify and describe the events that occur
    during meiosis.

48
Walter Sutton
  • In 1903, Walter Sutton, an ________ geneticist,
    added an important piece of information to the
    understanding of genetics. Sutton was studying
    the cells of __________________. He was trying
    to understand how sex cells form.
  • ___________ the male sex cell
  • ___________ the female sex cell

49
Walter Sutton
  • In 1903, Walter Sutton, an American geneticist,
    added an important piece of information to the
    understanding of genetics. Sutton was studying
    the cells of grasshoppers. He was trying to
    understand how sex cells form.
  • Sperm the male sex cell
  • Egg the female sex cell

50
Sperm and Egg
51
More on Sutton
  • Sutton became particularly interested in the
    movement of _____________ during the
    ________________ of sex cells.
  • Sutton hypothesized that ______________ were the
    _______ to understanding how offspring come to
    have _______________ similar to those of their
    parents.

52
More on Sutton
  • Sutton became particularly interested in the
    movement of chromosomes during the formation of
    sex cells.
  • Sutton hypothesized that chromosomes were the key
    to understanding how offspring come to have
    traits similar to those of their parents.

53
Chromosomes and Inheritance
  • Sutton knew that structures inside cells must be
    responsible for the inheritance of
    ______________. He needed evidence to support
    his __________________________ that
    _________________________ were those structures.
  • What he discovered

54
Chromosomes and Inheritance
  • Sutton knew that structures inside cells must be
    responsible for the inheritance of genes. He
    needed evidence to support his hypothesis that
    chromosomes were those structures.
  • What he discovered

55
Sutton Discovered
  • Grasshoppers have ____ chromosomes in each of
    their body cells.
  • Grasshoppers sex cells have only _____
    chromosomes.
  • The fertilized egg that forms has _______
    chromosomes.

56
Sutton Discovered
  • Grasshoppers have 24 chromosomes in each of their
    body cells.
  • Grasshoppers sex cells have only 12 chromosomes.
  • The fertilized egg that forms has 24 chromosomes.

57
Suttons Conclusion
  • Sutton concluded that the ___________ carried
    Mendels heredity factors, or __________ from one
    generation to the next. In other words,
    _____________ _______________________________.
  • Suttons idea became known as the __________
    _________ ___ ________ that states genes are
    carried from parents to their offspring on
    chromosomes.

58
Suttons Conclusion
  • Sutton concluded that the chromosomes carried
    Mendels heredity factors, or genes from one
    generation to the next. In other words, genes
    are located on chromosomes.
  • Suttons idea became known as the chromosome
    theory of inheritance that states genes are
    carried from parents to their offspring on
    chromosomes.

59
(No Transcript)
60
Meiosis
  • Meiosis is the process by which the number of
    chromosomes is _______ by half to form sex cells
    ______ _____ ______.
  • During meiosis, the chromosome pairs
    _____________ and are __________________ to two
    different cells. The resulting sex cells have
    only half as many chromosomes as the other cells
    in the organism.

61
Meiosis
  • Meiosis is the process by which the number of
    chromosomes is reduced by half to form sex cells
    sperm and eggs.
  • During meiosis, the chromosome pairs separate and
    are distributed to two different cells. The
    resulting sex cells have only half as many
    chromosomes as the other cells in the organism.

62
Mini Lab Mini Lab Mini Lab
  • Turn to page 105 in your text book.
  • Draw the stages of Meiosis.
  • Label and write a description (your own or what
    is in the book) of the four stages.

63
Meiosis and Punnett Squares
  • The Punnett square shows how ________ separate
    when sex cells form during meiosis. It also
    shows the possible __________ combinations that
    can result after fertilization occurs.
  • Tt
  • Parent Cells
  • Possible Sperm Cells
  • Tt
  • Possible egg
    cells

64
Meiosis and Punnett Squares
  • The Punnett square shows how alleles separate
    when sex cells form during meiosis. It also
    shows the possible allele combinations that can
    result after fertilization occurs.
  • Tt
  • Parent Cells
  • Possible Sperm Cells
  • Tt
  • Possible egg
    cells

TT
Tt
tt
Tt
65
Chromosomes
  • ____________ of the organism doesnt determine
    the number of chromosomes
  • _____________ have 46 chromosomes
  • _____________ have 78 chromosomes
  • _____________ have 56 chromosomes
  • Chromosomes are made up of many ____________
    joined together like beads on a string.
  • Your body has _____ pairs of chromosomes that
    contain more than _____________ genes. Each gene
    controls a _________ ____________.

66
Chromosomes
  • Size of the organism doesnt determine the number
    of chromosomes
  • Humans have 46 chromosomes
  • Dogs have 78 chromosomes
  • Silkworms have 56 chromosomes
  • Chromosomes are made up of many genes joined
    together like beads on a string.
  • Your body has 23 pairs of chromosomes that
    contain more than 60,000 genes. Each gene
    controls a particular trait.

67
Chromosomes
  • -
  • Genes are located on _________________.
  • They may have different __________ for some genes
    and the same for others.

68
Chromosomes
  • -
  • Genes are located on chromosomes.
  • They may have different alleles for some genes
    and the same for others.

69
Chapter 3, Section 4 The DNA Connection
  • After completing the lesson, students will be
    able to
  • Explain the term genetic code
  • Describe the process by which a cell produces
    proteins
  • Describe different types of mutations and how
    they affect organisms.

70
The Genetic Code
  • The main function of genes is to control the
    __________ of ______________ in the organisms
    cells.
  • __________________ help to determine the
    __________, _____________, and many other traits
    of an organism.

71
The Genetic Code
  • The main function of genes is to control the
    production of proteins in the organisms cells.
  • Proteins help to determine the size, shape, and
    many other traits of an organism.

72
Keeping it in perspective!
_______________
___________
______________
____ _______
73
Keeping it in perspective!
Chromosome
Cell
Nitrogen Bases
DNA Molecule
74
Review of Chapter 2
  • DNA is a major component of chromosomes.
  • DNA is made up of four different Nitrogen Bases
    adenine (A), thymine (T), guanine (G), and
    cytosine (C) these bases form the rungs on the
    DNA ladder.
  • A single gene on a chromosome may contain
    anywhere from several hundred to a million or
    more of these bases that are arranged in a
    specific order.

75
Cracking the Code
  • The order of the _____________ ____________ along
    a gene forms a _______ ___________ that specifies
    what type of ___________ will be produced.

76
Cracking the Code
  • The order of the nitrogen bases along a gene
    forms a genetic code that specifies what type of
    protein will be produced.

77
Cracking the Code
  • In a genetic code, a group of three bases codes
    for the attachment of a specific _________
    _______. _______ __________ are the building
    blocks of __________. The order of the bases
    determines the order in which ________ ________
    are put together to form a __________.

78
Cracking the Code
  • In a genetic code, a group of three bases codes
    for the attachment of a specific amino acid.
    Amino acids are the building blocks of proteins.
    The order of the bases determines the order in
    which amino acids are put together to form a
    protein.

79
How Cells Make Proteins
  • _______ ___________ is the production of proteins
  • During _________ __________, the cell uses
    information from a gene on a chromosome to
    produce a specific protein.
  • _________ _____________ takes place on the
    ______________ in the cytoplasm outside the
    nucleus
  • __________________ are inside the nucleus
  • HOW does the information needed to produce
    proteins get out of the nucleus and into the
    cytoplasm???

80
How Cells Make Proteins
  • Protein synthesis is the production of proteins
  • During protein synthesis, the cell uses
    information from a gene on a chromosome to
    produce a specific protein.
  • Protein synthesis takes place on the ribosomes in
    the cytoplasm outside the nucleus
  • Chromosomes are inside the nucleus
  • HOW does the information needed to produce
    proteins get out of the nucleus and into the
    cytoplasm???

81
(No Transcript)
82
The Role of RNA
  • The _______ ___________ is called ribonucleic
    acid or RNA RNA carries the genetic code from
    the DNA inside the nucleus into the cytoplasm.
  • RNA and DNA are similar, but DNA looks like one
    side of the ladder. RNA contains a different
    ______________ molecule then DNA. Instead of
    thymine, RNA contains __________.
  • _______________ ________ copies the coded message
    from DNA in the nucleus and carries the message
    into the cytoplasm.
  • Another type of RNA, called ______________
    __________, carries amino acids and adds them to
    the growing protein.

83
The Role of RNA
  • The genetic messenger is called ribonucleic acid
    or RNA RNA carries the genetic code from the
    DNA inside the nucleus into the cytoplasm.
  • RNA and DNA are similar, but DNA looks like one
    side of the ladder. RNA contains a different
    sugar molecule then DNA. Instead of thymine, RNA
    contains uracil.
  • Messenger RNA copies the coded message from DNA
    in the nucleus and carries the message into the
    cytoplasm.
  • Another type of RNA, called transfer RNA, carries
    amino acids and adds them to the growing protein.

84
Handout and Book Work
  • Turn to pages 110 and 111 in your textbook.
  • Complete the handout on Protein Synthesis.
  • When the handout is complete read pages 110-112
    in your textbook about Mutations.

85
Mutations
  • Some of the changes brought about by mutations
    are harmful to an organism. Other mutations,
    however, are helpful, and still others are
    neither harmful nor helpful.

86
Helpful Mutations
  • Monarch Butterfly
  • Viceroy Butterfly

Birds do not like the taste of monarch
butterflies. Many years ago the viceroy
butterflies looked different. Through various
mutations in appearance the viceroy looks like
the distasteful monarch butterfly.
About PowerShow.com