Download Genetics in Agriculture

http://www.youtube.com/watch?v=QS
N5gfbzgwc
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1.
Write questions, answer with video
Why do we use sexual reproduction?
Holiday Biotechnology
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1.
Write and answer with video:
Name the tree they raise? How do they
prepare Christmas trees for your home?
2.
What are steps used in assembling wreaths?
3.
What are the specific cultural requirements to
grow poinsettias?
Stem cuttings
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1.
Write questions answer with video:
What are the steps to follow for stem
cuttings?
2.
What are the different media they use?
3.
What is the last technique called?
Dole Bananas
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Write Questions and answer with video:
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Who cuts the bananas out of the field?
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How do they get them into the processing plant?
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How do they cool them down?
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How do they keep the stems from rotting?
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Plant Tissue culture
http://www.youtube.com/watch?v=PcBsJSHBU14
Orchid tissue culture:
http://www.youtube.com/watch?v=TiG4Mr930YI
Banana tissue culture
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http://www.youtube.com/watch?v=sLoZbDnAPIk
What steps do they do to prepare the tissue
culture?
What are the pro’s and con’s to growing them this
way?
How do they get them ready to plant in peoples
gardens?
Guided Summary
How many piglets per litter?
 What hormone was hypothesized that
increased litter growth?
 When do they begin puberty?
 Why do the male testes produce more piglets?
 What are most pigs produced through?
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Board Warmer
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1.
2.
3.
4.
Today as we begin reproduction I want to think about
and answer these questions:
Where did we come from? Where does all life
come from?
What are different ways organisms reproduce?
What are ways we can manipulate parent plants
and animals in order to get desired offspring
outcomes?
What desired outcomes are we looking for?
Asexual Reproduction
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Write questions, answer with video
1.
What have these flowers reproduced from?
2.
What does asexual mean?
3.
How does the liverwort reproduce?
4.
How are gardeners able to reproduce plants
asexually?
GENETICS IN AGRICULTURE
Objective 16.01: Discuss sexual reproduction in both
plants and animals.
Sexual Reproduction Processes
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1. Fertilization - The union of haploid cells in
both plants and animals.
 Occurs
in the ovary of plants and the uterus of
animals.
2. Embryo - a fertilized egg / ovule that will
grow to produce new offspring.
 3. Ovary - organ responsible for the
production of eggs / ovums in plants and
animals.
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Sexual Reproduction in Animals
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1. Fertilization occurs internally in
most animals - all mammals.
 a. Some fish and insects are
exceptions.
2. Haploid cells  a. Male cells are spermatozoa
(sperm) - released in semen to
aid in the process of
fertilization.
 b. Female cells are eggs produced in the ovary, fertilized
and developed within the uterus.
 i) Females release eggs on a
cycle (menstrual cycle) that
varies in time length.
Sexual Reproduction in Plants
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1. Pollination - the transfer of male pollen to the
female reproductive organs.
 a.
Pollination must occur before fertilization.
 b. Removal of the stamen is the first step in
mechanical cross pollination.
Sexual Reproduction in Plants
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2. Germination - the
initial vegetative
growth of a seed.
3. Male Reproductive
Parts - THE STAMEN
a. Anther - top of the
male part of a
flower, contains
pollen.
 b. Filament - long
slender stock on
which the anther sits.
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Sexual Reproduction in Plants
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4. Female Reproductive Parts THE PISTIL
a. Stigma - the swollen end of
the pistil, sticky to receive the
pollen.
 b. Style - stalk connecting the
stigma to the ovary- pollen on
the stigma forms long tubes
through the style.
 c. Ovary - produces and stores
the ovums (seeds), and protects
seeds during development.
 d. 1 ovum = 1 seed & 1 ovary =
1 fruit
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Sexual Reproduction in Plants
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5. Types of Flowers in Plants:
 a.
Complete- have all the parts of a flower (Stamen,
Pistil, Sepals, Petals).
 b. Incomplete- missing any part of the flower.
 c. Perfect- have all the reproductive parts of a flower
(Stamen & Pistil).
 d. Imperfect- missing any reproductive part of the
flower (Stamen, Pistil, or any part of either).
GENETICS IN AGRICULTURE
Objective 16.02: Summarize the process and
purpose of selective breeding techniques.
Selective Breeding Techniques in
Animals
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1. Progeny testing is used to determine the value
of male livestock by analyzing the transmission
of traits to offspring and its breeding potential.
2. Artificial insemination has proven to have the
greatest impact on animal breeding since the first
domestication of livestock.
Selective Breeding Techniques in
Animals
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3. Artificial Insemination
Process
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a. Semen is collected from male
individuals- methods vary
widely by the type of animal.
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i) Artificial vaginas are used for
larger mammals.
b. Semen is checked for viability
and flash frozen in specialized
straws.
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i) Straws should be placed in
storage tanks filled with liquid
nitrogen, till use
ii) Semen stored under proper
conditions has proven viable
decades later. (-320° F)
Selective Breeding Techniques in
Animals
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c. Female is treated with prostaglandin
(hormone) to induce estrus or heat.
d. Semen straws are immediately thawed in
water (99° F) and soon after inserted into the
mother using a specialized release gun.
Selective Breeding Techniques in
Animals
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4. Sperm Sexing - utilizes a cytometer cell sorter
to separate male sperm from female sperm.
 a.
Sperm with X chromosomes (female sperm) weigh
more (contain more DNA) than those with a Y and
can thus be dyed and separated because they absorb
more dye.
Selective Breeding Techniques in
Animals
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5. Invitro-Fertilization - method of removing eggs
from a mother for fertilization under laboratory
conditions.
 a.
A large number of eggs are collected from the
ovaries of an outstanding female and fertilized in
Petri dishes under laboratory conditions.
 b. Embryos can be inserted into surrogate mothers or
frozen for later use.
 c. Offers the most control and requires the least
amount of semen.
Selective Breeding Techniques in
Animals
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6. Birth Through Surrogate
Mothers a. Hormones are used to cause
the female to superovulate
(produce a large number of
eggs).
 b. Original mother undergoes
artificial insemination
 c. Fertilized eggs are removed
by a process called FLUSHING
to be placed in other female
animals for development.
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Cross-Pollination in Plants
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1. Definition- Method used to select particular
parents for the production of seed in plants.
Cross-Pollination in Plants
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2. Cross-Pollination Process:
 a. Plants possessing desirable characteristics are
selected and carefully monitored.
 b. Pollen can be gathered from male plants (or
flowers) months or in some cases, years in advance
and refrigerated for storage.
 c. Flowers on the female plant must be covered prior
to opening, and if capable of self-pollination, must
have the stamens removed.
 d. Once the female flowers open, pollen from the
male should be placed on the stigma, and the flower
covered again.
 i) Record keeping is critical in crossing plants.
GENETICS IN AGRICULTURE
Objective 16.03: Discuss asexual reproduction and the use of
cloning to improve genetics in plant and animal lines.
Cloning in Agriscience
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1. Allows rapid production of large
numbers of genetically identical
organisms.
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a. Agriculturists can quickly
disseminate outstanding traits.
2. Most often utilized for the culture
of plants - cheaper, easier process,
and less political opposition.
a. Tissue culture - the production of
plants from small amounts of
vegetative material in an invitro
environment, is an increasingly
popular and effective method of
plant production.
Cloning in Agriscience
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3. Animals are cloned almost exclusively by the
division of embryos. In recent years, diploid cells
have been cloned, but the process is extremely
expensive and results in high losses.
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i) Dolly the sheep was produced from mammary gland
cells in a sheep.
4. Clones are genetically identical (the exact same
DNA).
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a. Any genetic differences results from environmental
factors - disease, nutrition, physical injuries, etc..
GENETICS IN AGRICULTURE
Objective 16.04: Demonstrate proper technique in
simple asexual propagation of plants.
Stem Cuttings
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1. Section of the stem or a
branch is cut, treated with
rooting hormone, and placed in
soil or water to encourage the
development of roots.
2. Stem cuttings should always
be taken just above a node for
best rooting.
3. Most common method of
asexual propagation, used for
both woody and herbaceous
plants.
Air Layering
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1. Section of the stem or branch has the bark
removed or slightly damaged and a rooting hormone
applied. The area is then covered with soil wrapped
cellophane until well developed roots can be seen
through the plastic.
2. The branch or stem is cut below the roots only
after roots have fully developed.
Tissue Culture
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1. Common method of asexual production utilizing
extremely small amounts of plant material.
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a. Often uses meristem tips- the tip of a branch where
most active growth is occurring.
2. Tissue is removed from the plant, sterilized and
cultured on agar in aseptic conditions.
3. Meristimatic tissue develops shoots, is transferred
to another media to develop adventitious roots, is
hardened off, and finally transferred to soil.
Division
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1. Method of plant propagation conducted by
physically separating a plant into several smaller
plantlets.
2. Often used for grasses and Lilies.
A
variation is the production of non-tunicate bulbs
from scales. (each scale must contain a part of the
bottom of the bulb, the basal plate.)
Grafting- The process of removing plant material from
one plant for incorporation into another plant.
1. Often used with fruit trees to create
dwarf varieties.
 2. 2 parts
a. The Scion- the top portion of a graph
that will form the main part of the
plant.
b. The Rootstock- the bottom portion of
the graph that usually controls growth
habit (size of the plant) but produces
no vegetation.
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Grafting
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3. Budding is related to graphing- instead of using
a scion; exchange of plant material is accomplished
with a single bud.
4. SCION & ROOTSTOCK REMAIN GENETICALLY
DISTINCT EVEN AFTER COMBINATION.
Other Methods of Propagation
1.
2.
Leaf Cuttings
Root Cuttings
http://video.unctv.org/video/229317
8711/

Write and answer questions with video:
1.
What are the steps to air layering?
2.
What other layering does he perform?
3.
How long does it take to air layer?
4.
What are the results?
GENETICS IN AGRICULTURE
Objective 16.05: Explain methods of gene insertion used
in the creation of transgenic organisms
Characteristics of Transgenic
Organisms
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1. Can POTENTIALLY be created
using genes from ANY living
organism.
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a. The trick is finding a method for
insertion and successful expression.
2. Genetically modified organisms
transmit inserted genes at the same
rate as naturally occurring genes.
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a. Once a gene is inserted, it can be
passed on through sexual
reproduction.
Steps in the creation of a Transgenic
Organism
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1. Develop A Purpose / Goal- the transmission of
genes from one organism to another is both
expensive and potentially dangerous,
expectations for work should be laid out
carefully.
2. DNA must be extracted from the target
organism and the specific gene to be introduced
isolated utilizing restriction enzymes.
Steps in the creation of a Transgenic
Organism
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3. Vectors are used for the transmission of target genes.
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a. Viruses make good vectors, as they often insert DNA into
organisms they affect.
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i) Plasmids are the viruses most often used as vectors.
ii) Plasmids can store large strands of DNA or even one or more
chromosomes.
b. Some vectors can transmit genes simply through contact
with target cells in a liquid solution or by microinjection.
Steps in the creation of a Transgenic
Organism
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4. Isolated DNA is inserted into
the new organism by:
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a. Micromanipulation- the
isolated DNA segment is injected
into a target cell utilizing a
microscopic syringe under high
magnification.
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i) Most common for the creation
of transgenic organisms.
b. Biolistics- uses a gene gun to
fire gold plated .22 caliber shells
that have been covered with the
target gene into a mass of plant
cells.
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i) Most often used for plants, as
cell mortality is high.