Final Exam

Question 1

what are the main parts of a virus?

Answer 1

a nucleic acid (Rna or Dna) with protein coat surrounding it (capsids)

Question 2

How are hosts important in viral replication

Answer 2

viruses can’t replicate on their own, they rely on hosts

Question 3

what is a bacteriophage?

Answer 3

viruses that infect and replicate only in bacterial cells.

Question 4

lytic cycle

Answer 4

ATTACHMENT: attachment of virus onto host cell provided the virus can chemically recognize and lock onto specific groups on the cell’s surface
PENETRATION: whole virus or genetic material from virus enters host cells cytoplasm
REPLICATION/SYNTHESIS: DNA or RNA directs the host cell to make many copies of viral components
ASSEMBLY: viral nucleic acids and viral proteins are assembled into new viruses
RELEASE: host cell bursts to release new virus particles

Question 5

Lysogenic pathway

Answer 5

cycle is extended by latent period
1. Viral Dna is integrated into bacterial chromosome
2. Bacterium replicates all DNA including that of virus
3. After binary fission, each daughter cell has chromosome with viral DNA incorporated
4. Later, a molecular signal or other stimulus may reactivate the viral DNA. Then goes through lytic cycle

Question 6

what type of virus is HIV? what does it cause? how does HIV compromise the immune system?

Answer 6

retrovirus, causes aids, compromises the immune system by targeting CD4+ cells/ T Helper cells. These are responsible for mounting a defense against invading bacteria or viruses.

Question 7

New viruses are made each year to combat influenza virus. Explain

Answer 7

flu viruses mutate (undergo antigenic shifts) making it difficult to make effective vaccines. Different strains of subtypes vary in antigenic protein spikes

Question 8

what are emerging viruses?

Answer 8

viruses that originate in one organism then pass to another and cause disease

Question 9

how do viruses cause cancer?

Answer 9

viruses can trigger oncogenes(cancer cells) to become active. May also carry and integrate oncogenes into host cells genome.

Question 10

What are prions? what kinds of diseases are caused by prions?

Answer 10

prions are misfolded proteins that is an infectious particle. Prion’s cause TSE’s which is scrapie in sheep

Question 11

What are viroids? What kinds of diseases are caused by viroids?

Answer 11

infectious RNA with no protein coat; infect plants; use host protein to replicate

Question 12

What are features of prokaryotic cells?

Answer 12

unicellularity, make up domains bacteria and archaea, small circular dna usually have plasmids, cell division by binary fission, no membrane bound organelles, singular flagellum

Question 13

What types of organisms are in domain Archaea?

Answer 13

methanogens (produce methane gas) halophiles (salt loving organsims) thermoacidophiles (organisms thriving in hot, acidic environments)

Question 14

distinguish between gram-positive and gram-negative bacteria

Answer 14

gram positive: thicker peptidoglycan wall, stains purple
gram negative: less peptidoglycan; don’t retain purple dye; red counter dye results in dark pink color, outer membrane contains lipopolysaccharides

Question 15

what are 3 basic forms or shapes of prokaryotes?

Answer 15

rod-shaped, cocci, spiral

Question 16

what are plasmids? how are they involved with conjugation?

Answer 16

small accessory DNA molecules that many bacteria possess. transferred through direct physical contact between bacteria (conjugation) helps bacteria share their antibiotic resistance genes with neighbors

Question 17

what is transduction?

Answer 17

phages carry prokaryotic genes from one host cell to another. Transduction results from accidents that occur during phage replicative cycle. Method uses viruses

Question 18

what is transformation?

Answer 18

genotype and possibly phenotype of prokaryotic cell are altered by uptake of foreign DNA from surroundings. bacteria pick up genetic material from environment

Question 19

photoautotrophs

Answer 19

photosynthetic bacteria
example is cyanobacteria

Question 20

chemolithoautotrophs

Answer 20

autotrophic microorganism that obtains energy by oxidizing inorganic compounds

Question 21

photoheterotrophs

Answer 21

use light as source of energy but obtain carbon from organic molecules. Example are purple and green nonsulfur bacteria

Question 22

chemoheterotrophs

Answer 22

obtain both carbon and energy from organic molecules. Example are majority of prokaryotes including decomposers and most pathogens

Question 23

How are prokaryotes involved in cycling important elements such as carbon and nitrogen?

Answer 23

Fixation returns elements from inorganic form to organic forms that heterotrophs use. Carbon fixation involves incorporating the carbon CO2 into complex organic compounds. Nitrogen fixation involves certain bacteria converting N2 gas to ammonia NH3 and nitrate NO3

Question 24

how are bacteria used in genetic engineering

Answer 24

production of pharmaceutical agents such as insulin. used in production of enzymes, vitamins, and antibiotics

Question 25

how are bacteria used in bioremediation

Answer 25

sewage treatment plants, cleaning up oil spills, removal of contaminants from ground water

Question 26

what are the features of eukaryotic cells?

Answer 26

membrane bound nucleus containing Dna, multiple membrane bound organelles like mitochondria, endoplasmic reticulum, golgi apparatus, ability to divide through mitosis

Question 27

endosymbiosis theory

Answer 27

mitochondria evolved from aerobic bacteria that were engulfed by a larger cell. Chloroplasts also evolved from photosynthetic bacteria that were engulfed. free living bacteria were engulfed by another cell and became part of it providing energy to host cell

Question 28

what are two main means of locomotion used by protists?

Answer 28

flagella or cilia (used for swimming in liquid medium) pseudopodia (axopodia, filopodia)

Question 29

asexual reproduction in protists

Answer 29

mitosis, budding, schizogony

Question 30

sexual reproduction in protists

Answer 30

meiosis allows for genetic recombination

Question 31

features/characteristics of Diplomonads

Answer 31

two nuclei, unicellular, move with multiple flagella, modified mitochondria called mitosis. Examples: Giardia Intestinalis causes diarrhea. Parasite is found in contaminated water and can pass human to human

Question 32

features/characteristics in Parabasalids

Answer 32

undulating membranes, move with flagella, reduced mitochondria called hydrogensomes, trichonympha species lives in gut of termites and digests cellulose. Example is trichomonas vaginalis STD in humans. **Looks like a vagina

Question 33

features/characteristics of Euglenoids (members of Euglenozoa)

Answer 33

free living eukaryotes, pocket at one end with 1 or 2 flagella, mitochondria, flexible pellicle can change shape, 1/3rd of euglenoids have chloroplasts others lack chloroplasts and are heterotrophic, reproduction by mitosis no sexual reproduction. Example is Euglena

Question 34

features/characteristics of Kinetoplastids

Answer 34

unique single mitochondrion in each cell, evade immune response with "bait and switch defense". Trypanosomes are disease causing kinetoplastids. Examples: African sleeping sickness transmitted by tsetse fly. Leishmaniasis transmitted by sand flies. Chagas disease caused by Trypanosoma cruzi.

Question 35

features/characteristics of dinoflagellates

Answer 35

photosynthetic unicells, have 2 flagella in grooves of cellulose plates, both marine and freshwater, red tides result from blooms of dinoflagellates, produce powerful toxin that inhibits diaphragm causing respiratory failure in vertebrates, reproduce asexually

Question 36

What are red tides?

Answer 36

they result from blooms of dinoflagellates, they are detrimental to fishing industry, causes water to turn red

Question 37

features/characteristics of Apicomplexans

Answer 37

spore forming parasites of mammals, have apical complex of organelles, vacuoles, fibrils, microtubules at each end. EXAMPLE: Plasmodium which causes malaria. Anopheles Mosquito spreads plasmodium

Question 38

Life cycle of plasmodium

Answer 38

1. Anopheles mosquito injects into human saliva 2. Sporozites enter liver cells->mitotic cells divisions transforms to mereozoites that penetrate red blood cells 3. merozoites divide asexually in rbc then explodes to infect other rbc 4. Some merozoites form gametocytes 5. Another anopheles mosquito bites infected person and picks up plasmodium gametocytes and blood 6. Gametes form from gametocytes, each male gametocyte produces several slender male gametes 7. Fertilization occurs in digestive tract of mosquito, zygote forms (2n) 8. Meiosis

Question 39

features/characteristics of ciliates

Answer 39

have large numbers of cilia arranged in longitudinal rows or spirals, unicellular heterotrophs, sexual reproduction, some cilia may be fused into sheets, spikes, or rods that function as mouths paddles or feet, have a pellicle, conjugation involves exchange of micronuclei

Question 40

conjugation cycle

Answer 40

process where one organism transfers genetic material directly to another organism through physical contact 1. compatible mating types join together 2. makes diploid macronucleus 3. goes through meiosis and creates haploid micronucleus 4.one leaves and one goes through micronuclear fusion 5. original macronucleus disintegrates

Question 41

features/characteristics of brown algae (stramenopila)

Answer 41

most conspicuous seaweeds in northern regions (kelps), thallus= blade, stipe, holdfast algin= gel-forming substance used to thicken puddings, salad dressings undergoes alternation of generations. Commonly called "seaweeds". Lacks true tissues and organs

Question 42

alternation of generations

Answer 42

sporophyte (diploid) goes through meiosis to produce spores. gametophyte are smaller, filamentous individuals

Question 43

characteristics/features of golden algae

Answer 43

biflagellated, freshwater or marine, all photosynthetic, some mixotrophic, most unicellular some colonial, many can form protective cysts if environmental conditions deteriorate

Question 44

characteristics/features of diatoms

Answer 44

unicellular, photosynthetic organims, phytoplankton, double shells, made of opaline silica, can withstand pressure

Question 45

characteristics/features of Oomycetes (water molds)

Answer 45

all are parasites or saprobes, used to be categorized as fungi, have motile spores (zoospores) with two unequal flagella, zoospores produce asexually, sexual reproduction via male and female gametes, most live in water but terrestrial forms are plant pathogens. Phytophthora infestans causes late blight of potaties (Irish potato famine) Saprolegnia= fish pathogen; can infect amphibians and kill eggs

Question 46

features/characteristics of red algae (rhodophyta)

Answer 46

no centriole, no flagella, reproduce by alternation of generations, produce pigments to give red color. Porphyra=Japanese "nori" used to wrap sushi

Question 47

features/characteristics of plasmodial slime molds (AMOEBA)

Answer 47

multinucleate, moving mass of cytoplasm=feeding phase, usually yellow or orange, feed on bacteria, yeast and organic matter

Question 48

cellular slime molds (amoeba)

Answer 48

act like amoebas, eat bacteria, if food is scarce they form a moving "slug",

Question 49

Tubulinds (amoebas)

Answer 49

used to be gymnamoebas, large and varied group of amoebas, free-living, found in soil, freshwater, saltwater, heterotrophs feed on bacteria and other protists

Question 50

Entamoebas

Answer 50

parasites of vertebrates and invertebrates

Question 51

choanoflagellida

Answer 51

common ancestor of sponges, they have single flagellum surrounded by collar of shorter filaments, feed by straining bacteria from water with their collar

Question 52

life cycle of paramecium

Answer 52

asexual reproduction-binary fission sexual reproduction -conjugation

Question 53

what diseases are caused by water molds? (oomycetes)

Answer 53

Phytophthora infestans causes late blight of potatoes (irish potato famine) Saprolegnia=fish pathogen; can infect amphibians and kill eggs

Question 54

evolutionary significance of choanoflagellates

Answer 54

understandinf evolution of multicellularity and origins of animal life.

Question 55

How do amoebas move

Answer 55

by pseudopods/pseudopodia

Question 56

what are white cliffs of dover made of?

Answer 56

layers of soft, white, finely grained limestone

Question 57

distinguish between sporophyte and gametophyte

Answer 57

sporophyte is the diploid stage of a plant life cycle that produces spores through meiosis gametophyte is the haploid stage that produces gametes (sex cells) through mitosis

Question 58

describe general multicellular plant life cycle

Answer 58

alternation of generations and protected embryos, multicellular dependent embryos, walled spores produced in sporangia, multicellular gametangia, apical meristems are localized regions of cell division

Question 59

Unique features of bryophytes and examples

Answer 59

Non Vascular plants closest living descendants of 1st land plants. Examples are liverworts, mosses and hornworts

Question 60

functions of xylem and phloem?

Answer 60

two main tissues in vascular plants xylem- conducts water and minerals from roots Phloem- conducts sucrose (sugars) from hormones

Question 61

function of stems, roots, leaves, and seeds

Answer 61

stems photosynthesize roots provide structural support and transport capability leaves carry out photosynthesis seeds protect embryo from drying out and predators kinda

Question 62

what kind of plants are lycophytes

Answer 62

earliest vascular plants, spore bearing, club mosses, quillworts, and spikemosses

Question 63

The pterophytes include whisk ferns, horsetails, and ferns. What are features of each

Answer 63

whisk ferns- lost their roots and leaves horsetails- have jointed stems with brushlike leaves. Stems have silica deposits in epidermal cells of their ribs Ferns- have fronds that bear sori. Sori are sporangia located on underside of fern fronds. Gametophyte is heart shaped and can live independently

Question 64

what are evolutionary advantages of seeds?

Answer 64

protection of the embryo from harsh environments, built in food source for developing seedling

Question 65

identify the structures known as male gametophyte and female gametophyte

Answer 65

male gametophyte=pollen grain female gametophyte= embryo sac

Question 66

features of gymnosperm

Answer 66

plants with "naked seeds". Ovules are not completely enclosed in sporophyte tissue at pollination. All gymnosperms lack flowers and true fruits

Question 67

4 groups of gymnosperms

Answer 67

coniferophytes, cycadophytes, gnetophytes, ginkophytes

Question 68

features of angiosperms

Answer 68

flowering plants, enclosed ovules within diploid tissue at time of pollination, produce fruit from carpel

Question 69

what are the roles of some animals in the angiosperm life cycle

Answer 69

-fruits with fleshy coverings that are black, blue, or red are dispersed by birds or vertebrates - fruits with hooked spines (burs) are dispersed on animal fur or human clothing - squirrels and mammals bury acorns/nuts

Question 70

what is double fertilization and its outcome

Answer 70

one sperm fertilizes the egg forming a zygote. the other sperm fertilizes the central cell forming the endosperm. Endosperm will nourish the embryo

Question 71

what are the characteristics that distinguish fungi from other eukaryotes

Answer 71

fungi cell walls are made of chitin and filamentous structure made of hyphae allowing them to absorb nutrients fro environment through large surface area

Question 72

hyphae

Answer 72

feathery filaments that make up multicellular fungi. They release enzymes and absorb nutrients from a food source

Question 73

mycelium

Answer 73

root like structure of a fungus consisting of a mass of branching thread like hyphae

Question 74

spores

Answer 74

can form asexually or sexually and be dispersed by wind. They are microscopic reproductive cells that allow fungi to reproduce

Question 75

how do fungi absorb nutrients?

Answer 75

by secreting digestive enzymes onto food source, which break down complex organic molecules into smaller components

Question 76

zygomycota and examples

Answer 76

fungi that produce zygotes. Produce diploid zygote nuclei. Asexual reproduction is when sporangia release thin walled haploid spores, they disperse by wind. Sexual reproduction through plasmogamy which produces a sturdy structure called zygosporangium. Examples are Rhizopus that is found growing on moist bread/fruit

Question 77

What is Rhizopus?

Answer 77

Found growing on moist bread or fruit. This zygomycete feeds on simple sugars

Question 78

Basidiomycota and examples

Answer 78

The club fungi. Basifiocarp is visible reproductive structure. Examples are mushrooms, toadstools, puffballs, shelf fungi.

Question 79

ascomycota and examples

Answer 79

The sac (ascus) fungi. sexual reproduction occurs within the ascus. examples are bread yeasts, common molds, morels, cup fungi, and truffles

Question 80

Describe living components of a lichen.

Answer 80

lichens are example of symbiosis between different kingdoms. A lichen is composed of a fungus (usually ascomycete) along with cyanobacteria, green algae or both. They can live in harsh habitats. Break down rocks and help prepare for invasion of other organisms.

Question 81

what are mycorrhizae? How are they important?

Answer 81

fungi associated with roots of plants. extract nutrients from or exchange nutrients with their plant hosts. aid in direct transfer of phosphorus,zinc,copper and other minerals from soil to plant roots. Increase amount of contact with soil and increase surface area for absorption

Question 82

give examples of how fungal parasite or pathogens harm plants and animals

Answer 82

fusarium grows on spoiled food; produces vomitoxin that can cause brain damage in humans and animals. Aflatoxins are very carcinogenic produced by Aspergillus flavus strains growing on corn, peanuts, cotton seed. They can damage kidneys and nervous system of animals and humans. Corn smut damages corn but is not harmful to animals. Ergot associated with rye and cereal grains, an alkaloid toxin is produced and if eaten can cause hallucinations, gangrene, nervous spasms, burning sensations.

Question 83

fungal diseases in humans

Answer 83

ringworm, athlete's foot, nail fungus, thrush, oral or vaginal infections caused by Candida

Question 84

general features of all animals

Answer 84

heterotrophy, multicellularity, no cell walls

Question 85

what are 5 key innovations in animal evolution?

Answer 85

symmetry, tissues that allow for specialized structures or functions, body cavity, various patterns of embryonic development, segmentation or repeated body units

Question 86

differentiate between a pseudocoelom and a coelom

Answer 86

pseudocoelom- fluid filled body cavity found in some invertebrates such as roundworms coelom- fluid-filled body cavity of an animal that contains internal organs

Question 87

differences between protostomes and deuterostomes

Answer 87

protostomes= "first mouth" mouth develops from blastopore, anus comes second Examples: flatworms, nematodes, mollusks, annelids, arthropods) deuterostomes= "second mouth" anus develops from blastopore mouth comes second (echinoderms and chordates)

Question 88

advantages of segmentation?

Answer 88

efficient and flexible movement, redundant organ systems

Question 89

compare radial symmetry with bilateral symmetry

Answer 89

radial- longitudinal plane through central axis divides animal in two halves that are mirror images. Ex: Cnidaria Bilateral- body has right and left halves that are mirror images of each other. Ex: lobster

Question 90

what is cephalization?

Answer 90

evolutionary trend where organism develops head region at front of body containing sensory organs and nervous tissue, forming brain.

Question 91

3 germ layers and identify what body tissues arise from each

Answer 91

Ectoderm= outer layer gives rise to outer covering of body and nervous system Endoderm= inner layer gives rise to digestive system including intestines and organs like liver and lungs of vertebrates Mesoderm= middle layer gives rise to skeleton and muscles

Question 92

distinguish between open and closed circulatory system

Answer 92

open circulatory system= blood passes from vessels into sinuses, mixes with body fluid that bathes the cells or tissues, and then re enters vessels in another location closed circulatory system= blood is entirely confined to vessels and is physically separated from other body fluids

Question 93

archenteron and blastopore

Answer 93

archenteron is the primitive gut and blastopore is the opening into the archenteron

Question 94

distinguish between spiral cleavage and radial cleavage

Answer 94

spiral= new layer of cells nestles into space between older cells radial= pairs of new cells are positioned directly above older cells

Question 95

distinguish between determinate and indeterminate structures

Answer 95

determinate- development in which the type of tissue that each embryonic cell will form is determined early. Protostomes have this indeterminate- each cell remains totipotent and each cells fate is not determined for several cleavages. Deuterostomes have this