Bio exam 3 Flashcards
What are the three additions to cell theory?
- Energy flow occurs within cells
- Hereditary info is passed from cells to cells
- All cells have the basic chemical composition
cell division
makes new daughter cells from a parent cell
List and explain the three reasons why cell division occurs
- Reproduction: usually in unicellular organisms to increase the pop
- Growth and development- creates organs and complex systems
- Tissue repair: replacement of damaged cells
Interphase (G1, S and G2)
cell growth and copying of chromosomes in preparation for cell division
Mitotic (M) phase (mitosis and cytokinesis)
separation of copied chromosomes and cell division
G1 phase
active cell growth, bioploymers are being made, nutrients
And waste are flowing in and out
S phase
DNA replication occurs
G2 phase
cell growth and preparation for division
Cellular differentiation
is the process by which a less specialized cell becomes a more specialized cell type
Haploid
carry 1 copy of genome
Diploid
Carry 2 copies of genome
density- dependent inhibition
At high densities, the amount of growth factors and nutrients is insufficient to allow continued cell growth
anchorage dependence
most tissue-producing cells must be anchored to a surface in order to continue dividing. They anchor through the extracellular matrix.
tumor
mass of abnormal cells
benign tumor
the abnormal cells remain at the originating site. Most do not cause serious problems and can be fully removed by surgery.
malignant tumor
the cells become invasive enough to impair the functions of one or more organs
Cancer treatments
– Surgery
– Radiation
– Chemotherapy
G1 checkpoint
cell size is adequate, nutrients are sufficient, dna is undamaged
G2 checkpoint
chromosomes are correctly replicated, dna is undamaged, Mitosis activating proteins are present
M checkpoint
all chromosomes are attached to the spindle fiber
What are the key characteristics of Cancer?
- Has an abnormal amount of chromosomes
- Has malformed spindles
- Disorginzed arrangement
p53 Tumor Suppresor, a checkpoint protein
that stops the cell division to repair the dna or triggers
apoptosis.
Active Intravasation
uses proteolytic enzymes to allow cells to actively enter the blood stream
Passive Intravasation
cancer cells passively enters the blood stream. No energy is required
Stem Cells
cells that can become any type of tissue, used in regeneration
Pluripotent stem cells
embryonic , can divide into more stem cells or can become any cell type
growth factors
are proteins released by cells that stimulate other cells to divide
What is the final product in mitosis?
2 identical daughter cells
What is the final product in meiosis?
gametes
What is separated in mitosis?
Sister chromatids
What is separated in meiosis?
homologous chromosomes
