Meiosis
The number of chromosomes in a diploid human cell
46
(N = 23)
These can be found within the same numbered chromosome
Genes/traits
Egg and sperm
The cells that carry genes to an organism's offspring
Gametes (sperm and egg)
A black cat and a white cat breed and produce offspring that with grey fur. What term describes how fur color is inherited.
Incomplete dominance
You extract a cell from the ovum of a leopard. Is this cell:
Somatic or Germline?
Diploid or Haploid?
2N or N?
-Germline
-Haploid
-N
The process and stage in which crossing over occurs
Meiosis: (Prophase I)
A true breeding plant self pollinating will always yield offspring that...
Are identical to their parents
You discover a gene for fish scale color has two alleles; purple (dominant) and red (recessive). Come up with example genotypes (ex. Rr) to represent each possible phenotype
RR: Purple or Rr: Purple
rr: Red
Describe a trait that demonstrates codominance
A male and a female of a species perform 3 rounds of meiosis. Are more sperm or egg produced?
How many more types of one cell are there than the other?
9 more sperm than egg
Provide 3 reasons for why an African elephant would be a bad model organism
-Lots of resources to keep
-Long life cycle
-Complex organism
Name 3 scientists we have discussed this unit
-Gregor Mendel
-Thomas Hunt Morgan
-(Rosalind) Franklin
-(Katalin) Karikó
-(Jennifer) Doudna
-Provide the genotype and phenotype ratio of the offspring
Genotype: 1:2:1
Phenotype: 3:1
Even if one's genotype says they should express a certain trait, this can prevent that trait from arising
Epigenetics
Pairs of homologous chromosomes
Explain why genes/alleles located close together on the same chromosome are often inherited together
-Genes being close together means a smaller chance of crossing over occurring in between them
-Most of the time they are swapped to the other homologous chromosome together or not swapped at all
Why was Mendel so lucky that he chose pea plants (and their traits) to study?
What is the phenotypic ratio from a cross between a yellow wrinkled pea (Yyrr) and a yellow wrinkled pea (YYrr)
All yellow wrinkled
What is the phenotypic ratio from a cross between a Ccch rabbit and a cchc rabbit? What phenotypes will be observed?
A snail (N=18) spermatocyte fails to undergo anaphase II. How this would likely affect the sperm cells produced by this division? You may draw or explain your answer.
-Two diploid sperm cells (18 chromosomes)
-Two sperm cells with no DNA
A karyotype is taken of two different zygotes. #1 has an extra chromosome. #2 is missing a chromosome. Which zygote is more likely to die? Why?
Zygote #2. Missing genes often results in greater consequences than an extra copy of a gene
Explain how Mendel's work explains the segregation of alleles
One allele is passed on from each parents, resulting in a heterozygous F1 generation and mixed F2 generation
What is the phenotypic ratio from a cross between a yellow round pea (YYRr) and a yellow wrinkled pea (YyRr)
6: Yellow round
6: Yellow wrinkled
2: Green round
2: Green wrinkled
Explain how linked genes violate the law of independent assortment
Review slides for explanation