Download Bio 11 ANSWERS (midyear review, viruses, immune system

Bio 11 ANSWERS
(midyear review, viruses, immune system, taxonomy, monera and protists. Ch 7 & 8)
1. A virus is considered living because it can reproduce, but non living because it can only
reproduce in a host, does not use energy, grow or contain organelles.
2. Inside a virus is a DNA/RNA containing core (not a true nucleus), and the outside has a
protein coat known as a “capsid”. Some have a lipid membrane around the capsid.
3. Bacteriophage: a virus that destroys bacteria
Temperate phage: a bacteriophage that incorporates its DNA into a host cell and does not cause
lysis (is on the lysogenic pathway)
Virulent: a virus (bacteriophage) that causes lysis (bursting open) of host cells
Prophage: while its DNA is incorporated into the DNA of the host cell, a bactiophage is called
a “prophage”
4. Wide range: rabies
Narrow range: cowpox
5. see page 202
6. In the lytic pathway the virus will rupture (burst open) the host cell while in the
lysogenic pathway the virus inserts its DNA into that of the host cell but does not
destroy the host cell.
7. A “shock”, such as a change in temperature, can cause a virus to go from the lysogenic
pathway to the lytic pathway
8. Binomial nomenclature: Genus species
9. answers will vary (KPCOFGS)
10. Monera: mostly unicellular, no nuclei (prokaryotic)
Protista: mostly unicellular, have nuclei and organelles (eukaryotic)
Plantae: mulitcellular, feed through photosynthesis
Fungi: multicellular, feed through absorption
Animalia: multicelular, feed through ingestion
11. Skin: non specific defense, a physical barrier against all things, slightly acidic
Mucous membranes (nose, throat): mucous traps invaders while cilia create a current to move
them out of your body (non specific)
White blood cells: engulf and destroy invaders (non-specific)
Interferon: released by infected cells to interfere with the life cycle of the virus in cells in the
surrounding area (non specific)
Antibodies: attacks/destroys foreign invaders (one specific antibody attacks one specific type of
invader)
12. a chemical released by infected cells that interferes with viruses, making it difficult for
them to infect cells in the surrounding area.
13. A vaccine tricks the body into thinking it is being invaded by a virus. It contains either a
dead version of the virus, a harmless close relative of the virus or a sample of the virus
that is made harmless (attenuated). This provokes an immune response in the body,
which will them create antibodies to destroy that virus. If the patient then comes into
contact with the actual virus there will already be a defense system in place.
14. An ati-viral drug will lessen the affects of a virus (either by stopping it from reproducing
or leaving its host cells), while a vaccine will lead to the destruction of the virus
preventing a person from experiencing symptoms (see answer # 13 for more detail)
15. A viral vector is a benign (harmless) virus that carries sections of DNA into a host for
medical reasons, such as implanting the DNA for making normal hemoglobin into the
cells of a person who's body can't make normal hemoglobin.
16. Monera are prokaryotic and unicellular (mostly)
17. Schizophyta: largest group, contains eubacteria (can be auto or hetertrophs)
Cyanophyta: the blue green algae, live in water (hot springs, pools), are photosynthetic
Prochlorophyta: photosynthetic, live in marine organisms
Archaebacteria: split into three groups based on where they live (methanogens: swamps,
Halophiles: salty, Thermopiles: acidic and hot)
18. Bacilli: rods, Spirilli: spirals, Cocci: balls, Streptococci: longs chains of balls
19. Parasite: feeds on other living things without necessarily killing them
Saprophyte: feed on the dead
Photosynthesis: to gain energy form the sun
Chemosynthesis: to gain energy from chemicals
Obligate anaerobes: can't live if there is oxygen present
Faculatative anaerobes: can live with or without oxygen
Binary fission: asexual reproduction that single cells can do, where first the DNA is duplicated,
then the cell pulls apart into two new cloned cells
Conjugation: sexual reproduction in single celled creatures where some DNA in the form of a
plasmid it transferred from one organism to the other
20. Both respiration and fermentation provide energy. In respiration, more energy is created
and oxygen must be present. In fermentation oxygen does not need to be present, but the
products (other than energy) are harmful
21. Bacteria help in digestion, making yogurt, making cheese and cleaning up oil spills.
22. Using an antibacterial soap (or antibiotics) kills MOST bacteria, but some will survive.
The ones that survive do so because they have genetic traits that make them resistant to
that particular antibiotic. These traits get passed on to their offspring and, due to the
short life cycle of bacteria, you quickly have whole colonies of harmful bacteria that
you no longer have the ability to kill using that antibiotic.
23. Protists are single celled, but have nuclei and organelles.
24. Animal like protists all can be heterotrophs: Sarcodina (amoeba) feed by engulfing,
Ciliophora (paramecium) feed through an oral groove, and Sporozoa (malaria) is a
parasite.
Plant like protists all can be autotrophs: Euglenophyta can also be heterotrophs if there is no
light, Chrysophyta are useful in pool filters and toothpaste and Pyrrophyta causes the red tide
Fungi like protists are slimy: Gymnomycota leaves a slime trail and has a complex life cycle
25. Both amoeba and paramecium are single celled animal like protists that are heterotrophs.
They both excrete water through a contractile vacuole and can reproduce by binary
fission. The Amoeba has no defined shape and engulfs its food, while the paramecium
moves using cilia and feeds through its oral groove.
26. See page 231
27. see page 232