Lab Quiz 3 Flashcards
Cytoplasmic organelle duplication occurs during _________.
Interphase
DNA replication and chromosome duplication occur during _________.
Interphase
The cell cycle can be broken down into four stages. List the stages.
G1 - Growth
S - Synthesis - Growth & DNA replication
G2 - Growth and final prep for division
M - PMATC
Growth and DNA replication occurs during which stage of the cell cycle?
Synthesis (part of interphase)
G1
S
G2
M
Are all part of what phase?
Interphase
What is a centriole?
A short, cylindrical organelle that helps form spindle during cell division
What is the nucleolus for?
It is composed of RNA and is for ribosome formation
What are chromatids?
Identical parts of a chromosome following DNA replication
What does spindle do?
Brings about chromosome movement during cell division
What is a centromere?
The structure that holds sister chromatids together
spindle fibers are bundles of ___________.
Microtubules
The __________ cell is the cell that divides, the resulting cells are _________ cells.
Parental, daughter
What is happening during early prophase?
Centrosomes have duplicated
Chromatin is condensing into chromosomes
Nuclear envelope is fragmenting
What is happening during prophase?
Nucleolus has disappeared
Duplicated chromosomes are visible
Centrosomes begin moving apart
Spindle is starting to form
What is happening during prometaphase?
The kinetichore of each chromatid is attached to a kinetochore spindle fiber
Polar spindle fibers stretch from each spindle pole and overlap
What is happening during metaphase?
Centromeres of duplicated chromosomes align at metaphase plate
Kinetochore spindle fibers attached to the sister chromatids come from opposite spindle pores
What is happening during anaphase?
Sister chromatids become daughter chromosomes
Each pole receives the same number and kinds of chromosomes as the parent cell
What is happening during telophase?
Daughter cells are forming
Nuclear envelopes and nucleoli reappear
Chromosomes become indistinct chromatin
What is the division of cytoplasm called?
Cytokenisis
In plant cells, during telophase, division of the cytoplasm by formation of a _______ begins.
Cell plate
The nuclei in the daughter cells have the _____ number of chromosomes as the parental cell had.
Same
What happens during crossing-over?
the non-sister chromatids of a homologue pair exchange genetic material
What are the stages of Meiosis?
Prophase I Metaphase I Anaphase I Telophase I Interkenesis Prophase II Metaphase II Anaphase II Telophase II = Daughter cells
In females, meiosis I results in a secondary oocyte and one ___________.
Polar body
What is a polar body?
A nonfunctioning cell that will disintegrate
How many chromosomes are there in a gamete?
23
Following fertilization, a zygote has how many chromosomes?
46
2n = what?
Diploid
n = what?
Haploid
What is a diploid?
A nucleus containing the full number of chromosomes
What is a haploid?
A nucleus containing half the number of chromosomes.
How many viable sperm does spermatogenesis produce?
4
How many eggs does oogenesis produce?
1
True or false: only animal cells have aster
True
What is aster?
Short fibers produced by the centrioles important during mitosis and meiosis
Do plant cells have centrioles?
No, only animal cells have centrioles
In what stage does the nuclear envelope break down?
Prometaphase
In what stage do the spindle fibers attach to the kinetichore?
Prometaphase
At the start of ________, the centromeres split and the sister chromatids begin to move toward opposite poles of the s
pindle.
Anaphase
What is particulate theory?
- Inherited characters are determined by particular factors (genes)
- These factors occur in pairs
- When gametes form, these genes segregate so that only one of the homologous pair is contained in a particular gene
What are Mendel’s first and second laws?
1st - Law of Segregation
2nd - Law of Independent Assortment
A ______ is a unit of heredity on a chromosome.
Gene
What are alleles?
An alternate state of a gene, contributed to an organism by its parents.
Alleles that mask expression of other alleles but are themselves expressed are dominant, designated by a capital letter, are called what?
Dominant
Alleles whose expression is masked by dominant alleles are what?
Recessive
What is the difference between genotypes and phenotypes?
The genotype of an organism includes all the alleles present in the cell, whether dominant or recessive.
Phenotypes only include the physical appearance of the trait.
TT or tt would be an example of what?
A homozygous genotype
Tt would be an example of what?
A heterozygous allele
The first generation of offspring is called what?
The first filial or F1 generation
What are antigens?
a substance that evokes the production of one or more antibodies.
Name a few human traits that are determined by a single gene.
Widow's peak Bent little finger Albinism Attached earlobes PTC tasting Dimpled chin Hitchhikers thumb
What are some diseases inherited as single-gene traits?
Cystic Fibrosis
Huntington’s Diseas
Juvenile Retinoblastoma
The fragments of DNA that McClintock studied are called what?
Transposons
What is a homologous chromosome?
they look alike and carry the same traits.
What is interkinesis?
The period of time between meiosis I and meiosis II
