Lec 2 The Life of A Cell Flashcards
What are the two stages of the Cell Cycle?
Interphase ("resting phase")
Mitotic Phase (nuclear division)What are the 3 stages of Interphase?
G1 Phase, S Phase, G2 Phase
What occurs during the G1 Phase?
Normal cellular activities
cell growth + duplication of organelles
protein synthesis
What occurs during the S Phase?
DNA replication.
Cell is very vulnerable to events that can cause DNA damage
What occurs during the G2 Phase?
synthesis of protein, microtubules, etc
What are the possible fates of daughter cells?
- enter a new cycle immediately
- rest as an uncommitted cell
- differentiate -> age -> die
what occurs during cytokinesis?
cytoplasmic division
what are examples of cells that are extremely specialized and have lost their ability to divide?
red blood cells (mature) -> no nucleus
neuron (nerve cell)
muscle cell (increase in size, not number)
what are examples of cells that normally do not divide, but can be induced to do so by an appropriate stimulus?
liver cells
lymphocytes [WBCs]
which cells continuously undergo cell division?
skin cells
cells of the intestinal lining
bone marrow cells
*esp true for cells which are subject to frequent destruction.
what is the chromatin?
dna and protein. tangled/nucleus at rest
what is the chromatid?
duplicated chromosomes
what is a karyotype?
of and types of chromosomes an individual has (46)
Which cells are most vulnerable to damage during the S-Phase?
rapidly diving cells such as bone marrow, skin, and GI tract.
what are the 4 stages of mitosis? name them in order.
prophase
metaphase
anaphase
telophase
What occurs during prophase?
nuclear membrane disappears and chromosomes become condensed.
mitotic spindle forms
what occurs during metaphase?
paired chromosomes line along the equator of the cell
what occurs during anaphase?
chromosomes separate and migrate to opposite sides of the cell
what occurs during telophase?
nucleus divides into 2 cells which have the same composition of DNA
cytokinesis occurs (splits into 2)
What is the result of mitosis?
2 identical daughter cells are produced. these cells will enter the phases of the cell cycle and may either…
- immediately divide again
- rest
- remain permanently in interphase
difference between mitosis and meiosis?
mitosis involves cell division, occurs in most cells of the body, results in 2 daughter cells identical to the parent cell, and produces 23 pairs [46 chromosomes]
meiosis is cell division that occurs in the gonads or sperm. it results in 4 daughter cells which contain HALF the dna or chromosomes of the parent cell [23]
which term means decrease in size of cells?
atrophy
what is hyperplasia?
increase in mitotic activity
what is metaplasia?
change in cell response to disease, which results in the transformation of the cell into a diff cell type.
