| A | B |
|---|
| Apoptosis | Programmed cell death, brought about by signals that activate a cascade of suicide proteins; essential in development of nervous system and normal operation of immune system |
| Active Transport | Movement of molecules against a gradient from a region of low to high concentration |
| Passive Transport | Movement of molecules down a gradient from a region of high to low concentration |
| Meiosis | Produces gametes in gonads; consists of two divisions |
| Mitosis | Produces two genetically identical diploid daughter cells |
| CAM Plants | Open stomates at night and close them during the day; modified for dry environments |
| Calvin Cycle | Carbon fixation; produces a 3-carbon sugar; occurs in stroma |
| Light-Independent Reactions | Occur in stroma; do not depend on on light directly |
| Light-Dependent Reactions | Light is absorbed in the thylakoid membranes: ATP is produced, photolysis occurs, and NADP carries H2 to the light-independent reacion |
| Chromosome Structure | Kinetochores, centromere, and sister chromatids |
| Synapsis | Occurs in prophase of meiosis ! |
| Chiasmata | Site of crossover of nonsister chromatids |
| Mendel | Father of modern genetics; collected data from a large sample of plants and applied statistical analysis to his data |
| Incomplete Dominance | Characterized by blending |
| Codominance | In the hybrid condition, both traits show |
| Epistasis | Two separate genes control one trait, but one gene masks the expression of the other gene |
| Linked genes | Genes on the same chromosome are always inherited together |
| Sex-Linked Traits | Traits that are on the X chromosome |
| Karyotype | A procedure carried out to identify chromosomal abnormalities |
| Nondisjunction | An error that sometimes occurs during meiosis in which homologous chromosomes fail to separate |
| Autosomes | Chromosomes other than X and Y sex chromosomes |
| Fragile X Syndrome | Named for the physical appearance of the X chromosome; the tip of which seems to "hang by a thread" |
| Watson and Crick | Proposed the double-helix structure of DNA, received the Nobel prize |
| Transcription | The process by which DNA makes RNA |
| Translation | The process by which codons of mRNA are made into an amino acid sequence |
| Viruses | Consist of either RNA or DNA enclosed in a protein coat or capsid |
| Transduction | Phage viruses acquire bits of foreign DNA as they infect different bacterial cells and transfer them to other cells as part of the infection process |
| Lytic Cycle | Virus infects and takes over cell, replicates itself, causes the cell to burst, and releases a new generation of infectious viruses |
| Lysogenic Cycle | Virus infects cell but replicates without destroying the cells, becomes a prophage |
| Plasmid | Foreign, small, circular, self-replicating DNA molecule that inhabits bacteria and can express itself through the host bacterium |
| DNA Probe | Radioactively labeled single strand of nuclei acid |
| Operon | Important model for gene regulation; found in prokaryotes only |
| Polymerase Chain Reaction | Cell-free, automated technique by which a tiny piece of DNA can be rapidly copied |
| Complementary DNA | DNA made from RNA using reverse transcriptase |
| Gel Electrophoresis | Technique that separates molecules of DNA in an agarose gel in an electric field |
| Restriction Enzymes | Discovered in late 1960s in bacteria, where they are a defense against infection by viruses |
| Telomeres | Special nucleotide sequences found at the ends of eukaryotic DNA |
| Transposons | "Jumping Genes"; move around the genome |
| Prions | Infectious, misfolded proteins that cause sever brain diseases |
| Human Genome | Consists of about 30,000 genes and 3 billion base pairs |
