Exam 4 Flashcards
(31 cards)
What are the phases of mitosis (M phase)?
Prophase, Prometaphase, Metaphase, Anaphase, Telophase
Which part of the cell cycle includes G1, S, & G2?
Interphase, which is not part of mitosis
What is prophase?
Prophase is the first phase of mitosis. Chromosomes condense, the nuclear envelope breaks down, & the spindle starts to form
What is prometaphase?
Prometaphase is the second phase of mitosis. The spindle attaches to the chromosomes at the kinetochores & starts to line them up in the middle of the cell.
What is metaphase?
Metaphase is the third phase of mitosis. Chromosomes are aligned to form the metaphase plate. Chromosomes are under tension.
What is anaphase?
Anaphase is the fourth phase of mitosis. Sister chromatids separate & are pulled to opposite ends of the cell. This is the shortest phase
What is telophase?
Telophase is the fifth & final phase of mitosis. Nuclear envelopes form.
What is the part of the cell cycle called where the cell membrane splits in 2, finally forming 2 individual cells?
cytokinesis
What are the enzymes that regulate the cell cycle called?
Cyclin-dependent kinases (CDKs)
What is the main difference between meiosis II & mitosis?
DNA is not replicated in meiosis II. This produces haploid cells, meaning that there is only one of each chromosome.
What is mitosis? What is meiosis?
Mitosis is used to create an exact duplicate of a cell, while meiosis is used to crated a haploid cell for sexual reproduction.
Mnemonic: mi-TOE-sis happens in your toes
What is a germline cell?
It is a cell that will make gametes, but has not yet undergone meiosis. It is a diploid cell because of this.
What is a chiasma?
plural chiasmata
It’s the location on the chromosome where it crosses over in meiosis.
What does the synaptonemal complex do?
It connects the 2 homologous chromosomes during meiosis I.
In which phase of meiosis does the crossing over occur?
Prophase I
What did Mendel call genes?
Factors
What is the ratio for a dihybrid cross?
9:3:3:1
How do you combine the probability of mutually exclusive events?
add them
How do you combine the probability of independent events?
multiply them
What is nondisjuction?
It’s when homologous chromosomes or sister chromatids do not separate during meiosis, creating a gamate that does not have that chromosome & a gamate that has 2
Which shape represents each sex on a pedigree?
Square represents male. Circle represents female.
In general, what is the condition of having too many or not enough of a chromosome called?
Aneuploidy. Not down syndrome; That’s chromosome 21 specifically.
What causes aneuploidy?
Nondisjunction
What is reverse genetics?
Replacing a normal copy of a gene with a mutant in an attempt to figure out what that gene does.
