Monday January 25, 1999
Announcements: Review Session tonight at 110 Wartick Lab, from 6:30-7:30

Lecture notes:

Single Concept
1. Transcription occurs in the
a) mitochondrion
b) cytoplasm
c) nucleus
d) ribosome

2. Sucrose in a/an
a) amino acid
b) disaccharide
c) monosaccharide
d) polysaccharide

3. A chemical bond where two or more atoms share electrons is called
a) ionic b) hydrogen c) covalent

2^nd Level
1. In DNA, base pairing occurs between
a) A-G
b) U-G
c) C-G
d) T-U
e) C-T

Fill in the blanks (answers will be provided)
The __________ is the complementary copy of the triplet codon on the ___________ that codes for an amino acid.

Proteins

Proteins are the most diverse group of biological molecules. In addition to C, H and O proteins also contain Nitrogen (N) and can contain Sulfur (s).

Structural: collagen in connective tissue, spectrin in RBC

Contractile: actin and myosin in muscle

Hormone: insulin (peptide hormones) *not all hormones are proteins

Storage: the amino acid pool

Natural defense: antibodies, interferon

Transport: hemoglobin

Enzymes: amylase

All organisms are composed of cells.

Cells are the basic living unit of organization for all forms of life.

All cells arise from pre-existing cells.

Cells vary in Size: egg yolk (3cm) vs. E.Coli
Shape: amoeba vs. plant
Complexity: red blood cells vs. vision cell

Plasma Membrane: separtates the internal from the external environment and regulates interaction with the "outside".

Cytoplasm: Everything between the plasma membrane and the nucleus.

Nucleus*: membrane bounded compartment that houses the DNA and other molecules involved in reading, editing, and sending information.

* Bacteria have a nucleiod region with no membrane around the nuclear material.

Bacteria also have no organelles

Prokaryotes (Prokaryotic Cells)

Pro = before
karyote = nucleus

* The genetic material is in the nucleiod (a nuclear region which has no membrane).
* There are no organelles. Cellular functions take place in the cytoplasm.
* Almost all have cell walls for rigidity and protection.

Eukaryotes (Eukaryotic cells)

E = with
karyotic = nucleus

* All cells, except bacteria, are eukaryotic
* These cells have organelles which compartmentalize operations.

Why compartmentalize?
1. Keeps raw materials together.
2. Many operations are incompatible.
3. Some products need to be stockpiled and stored.

Nucleus: Area that contains chromosomes (DNA with proteins attached), nucleplasm (fluid), nucleolus (where ribosomes are produced), nuclear envelope (double membrane with numerous pores for passage of materials in and out of nucleus).

Endoplasmic Reticulum: ER - rough ER has ribosomes attached, smooth ER does not. Involved in modification of polypeptides into mature proteins and in lipid sythesis.

Golgi: Further processing, packaging, and directing of proteins and lipids

Mitochondria: energy metabolism (ATP formation)

Lysosome: For intracellular digestion (exp. Macrophage)

Transport vesicles: Move materials to and from organelles and plasma membrane.

Central Vacuole: (fungi and plants) Fluid filled compartment for rigidity and storgae.

Chloroplast: (plants) photosynthesis and temporary starch storage takes place here.

Cell walls: (most protists, bacteria, fungi and plants) rigidity and protection.

Centrioles: Involved in cell division in many types of cells. (Not in flowering plants or conifers, for example).

Flagella, cilia: Special organelles for motility.