Briefly describe the structure of a virus.
Outer capsid composed of protein subunits and a nucleic acid core composed of either DNA or RNA
2. Briefly describe the lytic cycle and the lysogenic cycle of bacteriophages.
Lytic Cycle: Release of new viruses lyses (ruptures) host cell
Lysogenic Cycle: Viral DNA inserts into host cell chromosome and does not actively replicate; viral DNA called prophage; prophage replicated along with bacterial chromosome; some later trigger can induce prophage to re-enter lytic cycle.
3. Briefly describe the life cycle of a retrovirus.
Nucleic acid is RNA; viral RNA gets into cell and is used to make DNA; DNA inserts into host chromosome; new viral RNA and capsid made by host cell; maturation and release follow; release by budding eventually kills cell.
4. Briefly describe 3 ways genes are transferred in bacteria.
Conjugation: two bacteria are temporarily linked together, often by means of conjugation pious. While they are linked, the donor cell passes DNA to a recipient cell in the form of a plasmid
Transformation: Occurs when a cell picks up free pieces of DNA secreted by live prokaryotes or released by dead prokaryotes
Transduction: Bacteriophages carry portions of DNA from one bacterial cell to another. Viruses have also been found to infect archaeal cells, so transduction may [lay an important role in gene transfer
5. What is the difference between an autotroph and a heterotroph?
Autotrophs make their own food, while heterotrophs rely on other organisms for food.
Briefly describe the three main shapes of bacteria.
Spirilli: spiral-shaped or helical-shaped
Bacilli: rod-shaped
Cocci: round or spherical
Briefly describe alternations of generations in plants.
Two multicellular individuals alternate; each producing the other; diploid sporophyte produces haploid spores; spore germinates into haploid gametophyte; gametophyte produces gametes, which fuse to form diploid zygote; zygote grows into sporophyte.
2. List and describe the parts of a complete flower.
Sepals: protect bud before it opens; collectively called calyx
Petals: colored leaflets; collectively called corolla
Stamens: male parts; filaments and anther; pollen produced in anther
Carpel: female parts; stigma, stalk, ovary
Complete flower has all four parts; incomplete flower lacks one or more parts
3. Match each of the following plants with the correct category
A. Bryophytes d_____Flowering plants
B. Seedless vascular plants c_____Cone bearing plants
C. Gymnosperms a_____Mosses
D. Angiosperms b_____Ferns
4. List the characteristics of all plants.
Multicellular, eukaryotes, usually specialized tissues, photosynthesizers that became adapted to living on land; alternation-of-generations life cycle; sessile
5. Define fruit.
A covering for a seed derived from an ovary
6. Briefly describe an archegonium and an antheridium.
Archegonium: female gametangia; produce eggs
Antheridium: Male gametangia; produces sperm
1. Describe the different types of symmetry.
Asymmetry: no particular pattern to body shape
Radial symmetry: Body organized circularly; similar to a wheel
Bilateral symmetry: Definite right and left halves; humans have bilateral symmetry
2. What are the differences between protostomes and deuterostomes?
Protostomes: Blastopore becomes mouth; ventral nerve cord ; spinal cleavage
Deuterostomes: Blastopore becomes anus; dorsal nerve cord; radial cleavage
3. What animals are in each of the following phyla? What characteristics are unique to each phyla?
A. porifera: sponges; no symmetry; no tissue; filter food particles from water
B. cnidaria: Jellyfish, corals, sea anemones; radial symmetry; tissues; stinging tentacles; olyp has mouth directed upward; Medusa has mouth directed downward
C. mollusca: Snails, clams, oysters, squid, octopus; all have a mantle, a visceral mass, and a foot
D. annelida: segmented worms; earthworms, leeches; body segments repeated along length of body
E. platyhelminthes: Flatworms; planaria, tapeworms; flat body; no body cavity
F. nematoda: Roundworms; non-segmented body; some are parasites
G. arthropoda: Exoskeleton; jointed appendages; segmented body; crustaceans; crabs, shrimp, lobsters, crayfish
H. Echinodermata: Starfish; deuterostomes, water vascular system; radial symmetry in adult; bilateral symmetry in larva
1. Define endothermic and ectothermic. Which vertebrates are endothermic? Which vertebrates are ectothermic?
Ectothermic: Body temperature stays relatively the same as the environment; Amphibians, reptiles, fish
Endothermic: Internal way to control body temperature; Birds, mammals
2. Define monotreme and marsupial.
Monotreme: Mammals that lay eggs; includes duck-billed platypus and spiny anteater
Marsupial: Mammals with pouches; young born very immature; complete development in mothers pouch, where mammary glands are located; includes kangaroos, koalas, and opossums
3. List the characteristics of all chordates.
Deuterostomes; postnatal tail; notochord; dorsal tubular nerve cord; pharyngeal pouches