Download Selective Breeding

Practice CRCT Question:
Mendel observed several traits that have
two different forms. For example, the
height of pea plants is controlled by two
different
a. Organs
b. Alleles
c. Hybrids
d. mutations
Activator:
• Brainstorm: Students will explain and
describe what they know about:
– Cloning
– Inbreeding
– Selective breeding
Today I will learn about selective
breeding because I need to know
how desired traits are chosen.
Selective Breeding
S7L3. Students will recognize how biological traits
are passed on to successive generations.
c. Recognize that selective breeding can produce
plants or animals with desired traits.
Advances in Genetics:
• Three methods that people have used to
develop organisms with desirable traits are
selective breeding, cloning, and genetic
engineering.
• Selective Breeding
• is process of selecting
a few organisms with
desired traits to serve
as parents of the next
generation.
• This is generally used
to increase the value
of the plant and
animal.
• Examples of Selective • Dairy cows are bred
Breeding
to produce larger
quantities of milk.
• Varieties of fruits and
vegetables are bred
to resist disease and
insect pests.
• Inbreeding
• involves the crossing of
two individuals that have
identical or similar sets of
alleles.
• This results in the
offspring having alleles
that are very similar to
those of the parents.
• The goal is to produce
breeds of animals with
specific traits.
• Examples of
inbreeding:
• Purebred dogs
• Horses
• Problems with
inbreeding:
• Inbreeding increases
the probability that the
organism may inherit
alleles that lead to
genetic disorders.
CFU:
• Explain how inbreeding could lead to
genetic disorders.
• Cloning
• Is the process used to
produce an organism
that is genetically
identical to the
organism from which
it was produced.
• This can be done with
plants and animals.
• Examples of cloning:
• Dolly the sheep
• Purpose:
• Scientists believe and
hope that cloning will
allow humans to live
healthier lives.
CFU:
What are some possible ethical issues that
could result from cloning?
• Genetic Engineering
• genes from one
organism are
transferred into the
DNA of another
organism.
• This is sometimes
gene splicing.
• Purpose of genetic
engineering:
• To produce medicines
• Improve crops
• Cure human genetic
disorders
CFU:
• What is genetic engineering? Describe
three possible benefits from this
technique.