2. Review of Cell Division To
Get the Ball Rolling...
What is Meiosis? What is Mitosis?
Click the Link!
3. Key Points in Meiosis:
⪢ One cell divides into four “daughter" cells
⪢ Makes gametes (egg and sperm)
⪢ Genetically different from “parent” cells
⪢ Each “daughter” cell contains half of the
genetic material or chromosomes of the
parent cell (n)
⪢ Essential for genetic variation to occur
⪢ Sexual reproduction
5. Key Points in Mitosis:
⪢ One cell divides into two “daughter” cells
⪢ Makes body cells
⪢ Genetically identical to “parent” cells
⪢ Each “daughter” cell contains the same
genetic material or chromosomes of the
parent cell (2n)
⪢ Does not allow for genetic variation to occur
⪢ Asexual reproduction
6. Mitosis in Cheetahs used to produce
more body cells for growth and repair.
Growth
7. New Key Points in Meiosis:
1. Crossing Over
2. Homologous Chromosomes
3. Independent Assortment
8. What is crossing over?
⪢ Homologous chromosomes pair up with each other
and exchange different segments of their genetic
material (DNA) to form new recombinant
chromosomes (has pieces of both chromosomes
combined)
⪢ Important source of genetic variation!
9.
10. What are Homologous Chromosomes?
⪢ A set of one paternal (father) and one
maternal (mother) chromosome that pair
up during mitosis.
⪢ Same size - carry the same genes in
the same loci (location)
⪢ May carry different alleles!
○ What’s an gainallele a?
11.
12. Who was Gregor Mendel?
⪢ Austrian Monk
⪢ Discovered the basic principles of heredity
through experiments in his garden
⪢ Famous for his work with pea plants
Click the Link!
13. Go the classwork section
and complete the Actively
assignment: Mendel’s Pea
Plants
14. What were Mendel’s Three Laws?
1. Law of Dominance
2. Law of Segregation
3. Law of Independent Assortment
15. What is the Law of Dominance?
⪢ One gene can mask another gene
⪢ The dominant gene masks the
recessive gene
16. What does dominant vs. recessive
mean?
Dominant Gene:
⪢ Represented by a
capital letter (F)
⪢ Masks the
recessive gene if
paired up
Recessive Gene:
⪢ Represented by a
lowercase letter (f)
⪢ Only shown if two
recessive genes
match up
17. RECESSIVE TRAIT IN CHEETAHS - KING CHEETAH
⪢ The striped pattern that gives
the King Cheetah its
distinctive look is a recessive
trait that only appears in two
cheetahs that contain this
trait.
⪢ When the cheetahs mate, in
some cubs born, this
recessive trait becomes the
dominant trait and-voila!- a
King Cheetah is born.
Only ~30
cheetahs in the
world have this
recessive trait!
19. Genotypes vs. Phenotypes
Genotype:
⪢ The genetic
makeup of an
organism
Phenotype:
⪢ The physical
appearance of
an organism -
determined by
the genotype
20. Storyline Mascot -
Cheetah
Phenotype:
The physical
appearanceof the
cheetahs.
Genotype:
The genetic makeup
of the cheetahs
which determines
their physical
appearance.
21. Possible Genotypes
1. Homozygous Dominant (FF) - two
dominant alleles together
2. Homozygous Recessive (ff) - two
recessive alleles together
3. Heterozygous (Ff) - one dominant and
one recessive allele together - the
dominant gene covers the recessive
gene
22. Go the classwork section
and complete the Actively
assignment: Mitosis vs.
Meiosis
23. Click on the link when you’re ready to take
the quiz: Unit 4 - Week 3 Quiz
It’s QUIZ time!
You smarty pants will
have no trouble...Good
luck!
point Quiz
