Download Selecting Desirable Traits

Selecting Desirable Traits
Section 4.2 p. 66
Learning Outcomes
• I can describe examples of genetic technology
• I can identify examples of natural selection, and
artificial selection
• I can describe methods being used with
biotechnology to better environmental issues
such as agriculture, and forestry
Artificial Selection
• Remember that Natural Selection is when the
environment “selects” which individuals will
survive long enough to reproduce
• Artificial Selection
• Is the process of selecting and breeding
individuals with desirable traits to produce
offspring that have these desired traits
• Animal breeders have practiced this method for a long time,
such as horses, cows, dogs, and many other types of animals
(this is where the idea of Purebred comes into play)
• Agriculture is another example of where humans have
practiced Artificial Selection as long a 10,000 years ago. The
plants no longer resemble the wild species from which they
came from
• Teosinte produced much smaller cobs and far fewer seeds than
modern day corn
Bio Technology
• Biotechnology is the use of living things
to make agricultural, industrial, or
medicinal products
• Natural means of artificial selection tends
to occur quite slowly, so scientist and
breeders have developed to techniques to
speed these process’s up
• These technologies can range from “low
tech” to extremely “high tech”
Cloning of plants
• Clone: a genetically identical copy of an entire
organism or of its cells or genes
• We learned of an asexual technique called cuttings
where you take a clipping of a plant, cut it off, plant
it, and it will grow to develop an identical plant
(clone)
• Problem is that ideal plants only have so many leaves
that can be cut off
• So scientists have created a quicker way to create
clones
• Cells are removed from the plant in question
• Cells are placed in a petri dish where they are
developed into seedlings
• The seedlings are then transplanted into the soil
Cloning of Animals
• Animals have been cloned for a variety of
reasons
• To help with research programs (alter the DNA)
• To help create the necessary amount of livestock
needed to produce meat and animal product
demands
• This is a highly controversial subject, and the
cloning that has been done has proved to
have many problems
• Unsuccessful preganecies
• Birth Defects
• Death among the clones
Artificial Reproductive Technology
• This refers to any artificial method of joining
a male and female gamete
• Two Main Types
• Artificial insemination; Sperm is harvested from a
male, and inserted into multiple females
• Advantage with animals is that it can help guarantee the
process occurs correctly, and that the male animals
sperm can be utilized in many places all at one time
• In vitro fertilization; sperm is harvested from the
male, the eggs are removed from the female. In
a laboratory petri dish the eggs are fertilized with
the male sperm producing embryo's
• Advantages many embryo's can be fertilized at one
time, and implanted into a number of females
• The result will be all the offspring being brother and
sister
Genetic Engineering
• Refers to any technology that directly alters the
DNA of an organism
• This science is rapidly developing to try and
control the characteristics of an organism to
better mankind
• This had led to many different types of GMO’s
(Genetically Modified Organism)
• Inserting the gene for insulin production into bacteria which
reproduce very quickly to produce enough insulin for
Diabetics
• Trying to cut down on pesticides used by farmers by inserting
genes from insect resistive strains of plants into those that
are normally affected
• This has a very negative affect on the overall variation
of the plants and animals that have been developed
Summary