Cell Biology and Mitosis

Flashcards generated from lecture notes on cells and mitosis.

Cell cycle

Continual process of growth and replication of cells

Interphase

Portion of the cell cycle during which growth is initiated and DNA is replicated

Mitosis

Portion of the cell cycle during which the cell divides its replicated DNA among two identical daughter cells

Phospholipid bilayer

A double layer of phospholipids in which the nonpolar fatty acid tails line up facing one another, and the polar phosphate heads line up to face the water-containing environments of the cell.

Cytoplasm

Region between the plasma membrane and the nuclear membrane that contains the cytosol, cytoskeleton, and organelles

Nucleus

Control center of the cell; contains the cell’s DNA

Nucleolus

Area within the nucleus that is responsible for RNA and ribosome production

Mitochondrion

Site of most of the cell’s ATP production

Ribosome

Site of protein synthesis

Peroxisome

Contains enzymes that detoxify chemicals such as hydrogen peroxide

Smooth endoplasmic reticulum

Series of membrane-enclosed spaces; site of lipid and cholesterol synthesis and metabolism; drug and toxin detoxification

Rough endoplasmic reticulum

Series of membrane-enclosed spaces; modifies proteins made by the ribosomes

Golgi apparatus (or complex)

Group of membrane-bounded sacs; modifies and packages proteins for export or use in the cell

Lysosome

Vesicular organelle that contains digestive enzymes that break down different substances within the cell

Centriole

Paired organelles composed primarily of microtubules that appear to be microtubule organizing centers and are important in facilitating the assembly and disassembly of microtubules

Cilia

Hairlike extensions from the plasma membrane that propel substances past the cell

Flagella

Single extension from a cell that propels the cell itself

Vesicle

Series of membrane-enclosed spaces; modifies proteins made by the ribosomes

Diffusion

The movement of solute from a high concentration to a low concentration

Osmosis

The movement of solvent from a solution with a lower solute concentration to a solution with a higher solute concentration through a selectively permeable membrane

Tonicity

Comparative measure of the osmotic pressure of two solutions and the ability of one solution to cause water movement by osmosis from another solution

Prophase - Events Taking Place in the Cell

Chromatin threads condense to form chromosomes; the nuclear membrane disappears; the mitotic spindle forms, and visible spindle fibers attach to the chromosomes

Prophase - Cell Appearance

Poorly defined nucleus; bar-like chromosomes

Metaphase - Events Taking Place in the Cell

Chromosomes line up in the center (or the equator) of the cell

Metaphase - Cell Appearance

Dark line of chromosomes is visible down the middle of the cell

Anaphase - Events Taking Place in the Cell

The chromosomes separate and are pulled to the opposite poles of the cell by spindle fibers

Anaphase - Cell Appearance

Separating, V-shaped chromosomes are visible with varying distances separating them

Telophase - Events Taking Place in the Cell

A cleavage furrow forms and cytokinesis takes place as the cytoplasm and organelles are doled out to the daughter cells; the chromosomes uncoil to form chromatin

Telophase - Cell Appearance

The cell looks as if it is being pinched; distinct chromosomes are often not visible; new nuclear membranes may be present

G1

During this phase of the cell cycle, the cell grows, synthesizes proteins, and is very metabolically active

S

During the S phase of the cell cycle, the cell replicates its DNA

G2

The G2 phase is characterized by the cell undergoing final preparations for cell division and cytokinesis. The cell manufactures enzymes and other proteins that are necessary for cell division to occur.

M

The M phase is where the cell undergoes mitosis, or cell division. The replicated DNA and cytoplasm are doled out to two new daughter cells, each of which are identical daughter cells.