29 terms

Biology Test: Cell Cycle, Mitosis, & Meiosis


Terms in this set (...)

Which biological macromolecule contains the information required to direct cell activities including growth and division?
Nucleic Acid
At what point in a cell cycle are complete sets of chromosomes visible?
Contrast the process of cytokinesis in plants and animals as well as bacterial binary fission.
plant cells-cell plate
animal cells-cleavage furrow
binary fission-cell contracts in middle to form 2 prokaryotic cells asexually
How many checkpoints exist in the cell cycle and what purpose do they serve?
three checkpoints; they serve to make sure everything is okay to proceed with cell division
Why is genetic diversity important in a population?
genetic diversity helps to bring about evolution in a species
Explain why it is necessary for gametes to be haploid.
gametes must be haploid in order to restore the diploid chromosome number in the zygote for that species
List 2 reasons that it is necessary for cells to divide.
because DNA unable to reach the cells needs and hard for the materials to cross the membrane
Describe the process by which DNA transforms from chromatin into condensed DNA found in chromatids and chromosomes.
DNA compacts by wrapping tightly around histones which form nucleosomes to condense into chromosomes.
List the 5 major phases of the cell cycle and identify the major actions in each stage.
G1(gap1)—cell grows and carries out normal functions, S (synthesis)—DNA replicates/copies, G2(gap2)—cell make organelles for cell division, M (mitosis)—division of the nuclear material(chromosomes), Cytokinesis—division of the cytoplasm of the cell to form 2 identical daughter cells This is also the order of the cell cycle. After cytokinesis G1 begins again.
What is the relationship between micro tubes, centrioles, and the spindle?
The microtubules give rise to the spindle fibers (made from microtubules) which attach to the centromere of the chromosome to separate the chromatids(chromosomes). The centrioles connect to the spindle and position themselves at the poles which help to separate the chromatids(chromosomes).
Describe what is happening during each of the four stages of mitosis.
Prophase—chromosomes condense and are first visible here, Metaphase—the chromosomes line up in the middle of the cell, anaphase—the sister chromatids pull apart and move towards he poles, telophase—the cell begins to split apart, nuclear membrane reappears, chromosomes begin to form into chromatin
What happens to cause normal cells to become cancerous cells?
Normal cells become cancerous when they lose the regulation of the cell cycle (cell growth and division)
Contrast diploid and haploid.
Diploid has the full set of chromosomes such 46 in a human somatic cell and haploid means half the number of chromosomes which is 23 in gametes (sperm and egg cell)
Draw a diagram that depicts meiosis in an organism with a diploid number of 2
Type of chromosome
Number per somatic cell Number per gamete
Autosome 44 22
Sex chromosome 2 1
Contrast sister chromatids with homologous chromosomes.
Sister chromatids are a duplicated chromosome whereas homologous chromosomes are the paired chromosomes letter C is sister chromatids and D is homologous chromosomes
When does crossing over occur during meiosis, how does it occur and what is accomplished in the process?
Crossing over happens during prophase I, it the exchange of segments of DNA between members of pairs of chromosomes, and it produces genetic variation in a species
Which processes in meiosis create new genetic combinations?
Crossing over
Unequal cytoplasmic division occurs during meiosis. When and why does this occur?
Unequal cytoplasmic division occurs in the female production of egg cells.
Contrast parthenogenesis with sexual reproduction
22. Sexual reproduction involves two parents in the fusion of sperm and egg. Parthenogenesis is the development of the egg into a new organism without being fertilized by sperm so no sexual reproduction involved.
Describe the structure of spindle fibers.
Spindle fiber are made up of microtubules
What stages of the cell cycle occur during interphase?
g1, s, g2 phases
when are the homologues visible during meiosis?
during prophase one metaphase one
Separate in meiosis 1
What 2 major accomplishments are made by the process of meiosis?
Meiosis makes sure number of chromosomes is half in the gametes as compared to the body cells.
Compare and contrast the processes of budding and binary fission.
Binary fission is asexually reproduction of prokaryotes. Budding is an asexual reproduction in eukaryotes such as hydra. Other types of asexual reproduction are vegetative reproduction and fragmentation
What does cell division produce?
new cells with an exact copy of genetic information.
What happens after replication?
there are half as many centromeres as there are chromatids
What happens at G2 checkpoint?
DNA is checked by repair enzymes
During anaphase of mitosis and during anaphase I of meiosis what happens in both?
During anaphase of mitosis the chromatids separate and during anaphase I of meiosis the homologous chromosomes separate
What does Cytokinesis does not do?
Cytokinesis does not bring about new genetic combinations