Unit H – Applied Genetics in Agriculture and Agriscience
Sexual Reproduction Processes
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Fertilization o Union of in both plants and animals
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Occurs in the ovary of plants and the uterus of animals
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Embyro
 o A egg/ovule that will grow to produce new offspring o Organ responsible for the production of eggs/ovums in plants and animals.
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Fertilization o Occurs in most animals – all mammals.
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Some fish and insects are exceptions
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Haploid Cells o Male cells are (sperm), released in semen to aid in the process of fertilization o Female cells are , produced in the ovary, fertilized and developed within the uterus
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Females release eggs on a cycle (menstrual cycle) that varies in time length according to species.
Sexual Reproduction in Plants
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Pollination o The
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Pollination must occur before fertilization
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Removal of the stamen is the first step in mechanical cross pollination
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Germination o The
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Reproductive Parts of Plants
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Male – THE o Anther – top of the male part of a flower, contains o
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Female – THE
– long slender stock on which the anther sits o Stigma – the swollen end of the pistil, to receive the pollen o – stalk connecting the stigma to the ovary, pollen on the stigma o Ovary – produces and stores the ovums (seeds), and o 1 ovum = I seed & 1 ovary = 1 fruit
Reproductive Parts of Plants
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Types of Flowers in Plants
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– have all the parts of a flower (stamen, pistil, sepals, petals)
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Incomplete – missing any part of the flower
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Perfect – have all the reproductive parts of a flower (
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)
– missing any reproductive part of the flower (stamen, pistil, or any part of either)

Asexual Reproduction & Cloning
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Cloning in Agriscience o Allows rapid production of large numbers of
organisms.
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Agriculturalists can quickly disseminate outstanding traits. o Most often utilized for the culture of plants – o The ability to differentiate is more in plants than animals
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Tissue culture o the production of plants from small amounts of vegetative material in an o an increasingly popular and effective method of plant production.
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Animals are cloned almost exclusively by the division of . o In recent years, diploid cells have been cloned, but the process is extremely expensive and results in high losses.

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Clones are (the exact same DNA) o Any genetic differences results from environmental factors
 Disease, nutrition, physical injuries, etc.
Asexual Propagation of Plants
16.04 – Demonstrate proper technique in simple asexual propagation of plants

Stem Cuttings o Section of the stem or a branch is cut, treated with and placed in soil or water to encourage the development of roots. o Should always be taken just above a node for best rooting o o Used for both

Air Layering
and o Section of the stem or branch has the
plants.
and a rooting hormone applied. o Area is then covered with soil wrapped cellophane until well developed roots can be seen through the plastic o Branch or stem is cut below the roots only after roots have fully developed.
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Tissue Culture o Common method using

Often uses
amounts of plant material
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The tip of a branch where most active growth is occurring o Tissue is removed from the plant, sterilized and cultured on agar in aseptic conditions o tissue develops shoots, is transferred to another media to develop adventitious roots, is hardened off, and finally transferred to soil.

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Division o Method of plant propagation conducted by
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Often used for grasses and lilies
a plant into several smaller plantlets
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A variation is the production of non-tunicate bulbs from scales
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Each scale must contain a part of the bottom of the bulb, the basal plate
 o Process of removing plant material from one plant for incorporation into another plant
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Often used with fruit trees to create dwarf varieties
 Two parts
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– top portion of a graft that will form the main part of the plant
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– bottom portion of the graft that usually controls growth habit (size of the plant) but produces no vegetation o is related to grafting
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Instead of using a scion, exchange of plant material is accomplished with a single bud o Scion and rootstock remain combination
even after
Transgenic Organisms - 16.05 – Explain methods of gene insertion used in the creation of transgenic organisms
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Characteristics o Can potentially be created using genes from organism
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The trick is finding a method for insertion and successful expression o Genetically modified organisms (GMOs) transmit inserted genes at the same rate as
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Once a gene is inserted, it can be passed on through sexual reproduction
Steps in Creating a GMO o Develop a
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Transmission of genes from one organism to another is both
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Expectations for work should be laid out carefully o DNA must be extracted from the target organism and the specific gene to be introduced isolated utilizing o
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are used from the transmission of genes
make good vectors, as they often insert DNA into organisms they affect
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Plasmids are the viruses most often used as vectors
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Plasmids can store or even one or more chromosomes

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Some vectors can transmit genes simply through contact with target cells in a liquid solution or by microinjection. o Isolated DNA is inserted into the new organism by:

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Isolated DNA segment is injected into a target cell utilizing a microscopic syringe under high magnification o Most common

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Uses a to fire gold plated .22 caliber shells that have been covered with the target gene into a mass of plant cells o Most often used for plants, as cell is high