Mitosis
Name two important functions for cell division?
It enables multicellular organisms to develop from unicellular organisms. It allows cells to replace other cells that die off. There are other options as well.
DNA molecules are made into chromosomes to make replication easier. True/False
What are chromosomes made of? Chromatin
The cell cycle is the life of a cell starting from when it is first formed up until its own division.
Sister chromatids represent a single strand of unreplicated DNA. True/False
Centromeres are the region where the sister chromatids of a chromosome are most closely attached.
What is the difference between somatic cells and gametes?
Somatic cells are diploid and have one set of chromosomes from each parent. Gametes are haploid and used to produce a zygote.
Describe the difference between G1, S, and G2 phases.
G1 is simply a growth period, S is the DNA replication phase, and G2 is growth and preparation for cell division.
If a cell fails to meet the G1 checkpoint, it will enter the G0 phase. Most cells in the body are in this phase. True/False
What is the difference between mitosis and cytokinesis?
Mitosis is division of the nucleus whereas cytokinesis is division of the cytoplasm.
The mitotic spindle is a structure made of microtubules and proteins that is important for many events in mitosis. At opposite poles of the structure are centrosomes which are required to organize the microtubules.
Microtubules attach at the kinases that are located on the centromere. True/False
Describe the process of mitosis by naming and describing all the phases.
Prophase- chromatin condenses, nucleoli disappear, centrosomes move apart
Prometaphase- nuclear envelope fades, mitotic spindle forms, microtubules attach to the newly formed kinetochores
Metaphase- centrosomes are at opposite poles, the chromosomes line up at the metaphase plate
Anaphase- chromatids separate, move to opposite ends of the cell
Telophase- two nuclei form in the cell, chromosomes decondence
Cytokinesis- cell divides
Cell division produces two genetically identical daughter cells. True/False
In animals cells, cleavage is the means by which they divide. This can be seen by the appearance of the cleavage furrow. Plant cells differ in that their Golgi apparatus produces vesicles that form a cell plate during telophase.
Do prokaryotic cells perform mitosis? Do eukaryotes cells perform binary fission? No, Yes
Describe the difference between density dependent inhibition and anchorage dependence.
Density dependent inhibition- when cells become too crowded they stop dividing
Anchorage dependence- after a single layer of cells form on a substrate the cells stop dividing
A growth factor is a protein the stimulates cells to divide. True/False
What type of gene causes the molecular event that may lead to cancer?Oncogene
Describe the relationship between the cell cycle and cancer.
Cancer cells are limited by the absence of growth factors. They stop dividing at random points in the cell cycle, and they can divide indefinitely.