Biology 100

• Cells without true nucleus.
• Ex. Bacteria

• Part of procaryote cell
• Site of protien synthesis

Cells with a true nucleus

• Part of eucaryotic cells
• Fibers of DNA

• Digestion
• Chemical storage
• H₂O balence
• Cell enlargement

Converts solar energy to sugar molecules

• Powerhouse; Convert energy
• Ex. Glucose => ATP
• Where most ATP is produced
• Where most cellular respiration occurs

• Mass of chromatin, DNA, RNA, & protiens
• Where ribosomes are costructed

• Digest materials
• Fuse with white blood cells to destroy bacteria
• Transport vehicle

• Ribosomes on membrane
• Site of protien synthesis
• Where cell membrane is produced

• Found in the liver
• Production of lipids
• Detoxification of drugs, degrades alcohol & cholesterol
• Formation of hormones & steroids
• Stores calcium ions in muscles

• Distribution Center
• Recieves, stores, modifies, & distributes chemical products of the cell

Particles spread out from more concentrated areas to less concentrated across a permeable membrane

Passive transport of H₂O

Protiens move substances thru cell walls

• 2 Types:
• Endocytosis
• Exocytosis

Moves particles in

Moves particles out

Cellular eating

Higher concentration of solutes

Lower concentration of solutes

Equal concentration of solutes

Capacity to do work

Energy to actually do work

• Endergonic Reactions
• Exergonic Reactions

• Require energy
• Ex. Photosynthesis

• Releases energy
• Ex. Wood burning

Creating energy from food molecules by your cells

Cell takes apart a glucose molecule & taps the energy carried by electrons being rearranged when old bonds break & new ones form

C₆H₁₂O₆ + 6O₂ --> 6CO₂+ 6H₂O + ENERGY (ATP)

• Reductions = addition of electrons
• Oxidation = loss of electrons

• Mechanical - movement of cilia
• Transport - brain cells pump ions across their membranes
• Chemical - linking amino acids -> protiens

• Glycolysis
• Kreb's Cycle
• Electron Transport Chain

Happens in cytoplasm

Glucose => Peruvic Acid + Energy (ATP, NADH)

Happens in mitochondria

Peruvic Acid -> C-C-C ^{->CO₂ kicked off}

C-C(acetic acid) + CoEnzyme A + ATP

• Happens in mitochondria membrane
• Stores electrons from stages 1 & 2 to make most cells ATP

Have less energy than shorter wavelengths

• Ultimate source of food for every organism
• The most important chemical process on Earth

6CO₂ + 6H₂O --> C₆H₁₂O₆ + 6H₂O + 6O₂

• Occurs in thylakoid membrane
• Absorbs solar energy
• Converts to chemical energy stored in ATP & NADH
• Doesn't produce sugar, only energy!

• Union of sperm & egg
• Creates genetic variation

• Production of offspring by a single parent without egg & sperm
• Produces exact genetic replicas
• Also called binary fussion
• Ex. Bacteria reproduce this way

• Daughter cells with same # of chromosomes
• Identical copies

Reduces # of chromosomes by ¹/₂

A pair of chromosomes that look alike & carry the same genes for the same trait (exception, sex chromosomes)

• Have true nucleus
• When nucleus is not dividing DNA is a tangled mass of thin threads called chromatin
• When it starts dividing DNA becomes highly coiled & condensed called chromosomes

• Interphase - Cell prepares to replicate
• Mitosis - Nuclear division resulting in the same # & kind of chromosomes in daughter cells as parent cells
• Cytokinesis - Division of cytoplam

Period before DNA synthesis increases in: protiens, organelles, size, MTOC & centriole pairs appear

DNA synthesis begins resulting in two sister chromatids (single DNA strand)

Time from DNA synthesis to the onset of cell division

• Prophase
• Metaphase
• Anaphase
• Telophase

• Chromatin fibers condense, chromosomes visable
• Nucleolus disappears
• MTOC's begin to move towards poles
• Miotic spindle grows out of nuclear membrane fragment

• Sister chromatids line up on equator of cell
• MTOC's at poles
• Spindle apparatus fully formed
• * Centromere - where sister chromatids are connected

• Centromeres divide & chromosomes seperate
• Daughter chromosomes move towards poles

• Nuclear envelope forms around daughter cells
• Nucleolis reappears
• Chromosomes become diffused chromatin

Cell division

Cells with a single set of chromosomes

• Sex cells with haploid # of chromosomes
• Ex. Sperm & eggs

Homologous set of chromosomes (2 chromosomes)

• Interphase
• Prophase I
• Metaphase I
• Anaphase I
• Telophase I
• Cytokinesis

• Chromosomes replicate = 2 genetically identical sister chromotids
• MTOC's with centriol pairs appear

• Most complex stage
• 90% of cell reproduction cycle occurs here
• Homologous chromosomes with identicals sister chromatids pair up forming a tetrad (4 chromotids)

Tetrads line up on metaphase plate

Chromosomes moving toward poles

• Chromosomes arrive at poles
• Nuclear envelope appears

Cytokinesis shows clevage furrow

Is basically like a miotic division without chromosome replication

• Chromosomes condense
• Spindle forms
• Nuclear envelope fragments

Chromotids line up on metaphase plate

Sister chromotids seperate

4 haploid daughter cells (sperm or egg)

• Original chromosomes break apart & exchange genetic information
• Happens in prophase

• Chromosomes align independently (randomly) at metaphase plate
• Maternal or paternal chromosomes may be oriented toward either pole
• Happens in metaphase

Normal cells in your body die after approximately 50 replications, cancer cells are immortal

• Don't have a properly functioning cell cycle control system therefore divide excessively
• Uncontrollable growth

Excessive cell growth resulting in an abnormal mass of cells

Abnormal mass of normal cells that remain at original site in body

• Cancerous!
• Capable of spreading out to surrounding tissues or other parts of body

Spread of cancer cells beyond original site

• Originate on external or internal coverings
• Ex. Skin, intestinal lining

• A rise in tissue
• Ex. Bone, muscle

Cancers of the blood foring bone marrow, spleen, lymph nodes

Genes that cause cancer

Have potential to become oncogenes

• Taken from 5 day old blastocyst (blastula)
• Will differentiate into any type of cell

• Scarcer that embryonic stem cells
• Limited to tissue of origin

• Stem cells from newborn
• Produce only blood cells (red & white & other parts of immune system