in semester practice exam questions

Question 1

one piece of evidence that supports the hypothesis that animals are related to choanoflagellates is that

Answer 1

the inner cavity of sponges, the spongocoel, is lined by cells that resemble choanoflagellates

Question 2

stinging cells of cnidarians are called

Answer 2

cnidocytes

Question 3

the digestive system of cnidarians is called a gastrovascular cavity because it

Answer 3

distributes nutrients, oxygen and wastes to different regions of the body

Question 4

animals w a distinct head region, an anterior brain, and displaying forward, directed locomotion in some part of their life have the following form of body symmetry

Answer 4

bilateral symmetry

Question 5

3 embryonic germ layers are

Answer 5

endoderm, mesoderm, ectoderm

Question 6

the trypanosoma brucei species complex contains species that are:

a. Flagellated protistans (SCEs same thing)
b. Parasites of the blood of mammals;
c. Cause the disease nagana in domestic cattle in Africa;
d. Able to invade the central nervous system of their infected hosts;
e. All of a-d above.

Answer 6

all of the above

Question 7

coccidians are apicomplexans responsible for many diseases of many animals including chickens. Coccidians:
a) infect cells in GI tract
b) produce a cyst, called the oocyst, that protects the organisms in the external environment
c) display asexual and sexual reproduction in its life cycle
d) all of the above

Answer 7

all of the above

Question 8

members of the apicomplexan genus babesia are important pathogens of cattle. Cattle become infected with babesia when:

Answer 8

an infected cattle tick injects babesia parasites w saliva into the bovine

Question 9

in comparison to animal cells, plant cells lack:
a) flagella and cilia
b) centrosomes
c) centrioles
d) lysosomes
e) all of the above

Answer 9

all of the above

Question 10

the organism thought to be the closest living relatives of the animals (metazoans) belong to a clade known as the

Answer 10

choanoflagellates

Question 11

form of interspecific association where one organism lives inside another organism and first derives benefit from the association while causing harm to the second is called;

Answer 11

parasitism

Question 12

form of body symmetry associated w directed locomotion and cephalization is

Answer 12

bilateral symmetry

Question 13

viruses that cause the diseases dengue, zika and yellow fever are transmitted to humans by

Answer 13

mosquitoes

Question 14

43. Which of the following statements about viruses is NOT correct?
    a. Viruses are metabolically inert outside the host cell;
    b. Viruses possess only one type of nucleic acid;
    c. Viruses multiply by binary fission; agree - hijack host cell metabolism and resources to replicate themselves
    d. Viruses cannot produce their own energy or macromolecules;
    e. In their most basic form, viruses consist of nucleic acid surrounded by a protein coat;alive

Answer 14

c) they don’t multiply by binary fission

Question 15

to answer: are viruses alive? which of the following is most important to consider

Answer 15

viruses have the genetic potential to replicate and evolve

Question 16

which of the following organelles are NOT components of animal cells
nuclei, central vacuoles, centrioles, flagella, cilia

Answer 16

central vacuoles

Question 17

members of phylum cnidaria are

Answer 17

diploblastic metazoans, displaying radial symmetry and bearing stinging cells called cnidocytes

Question 18

the theory to explain the origin of eukaryote life is

Answer 18

endosymbiosis theory

Question 19

for feeding, members of the phylum porifera

Answer 19

draw water into internal cavity, the spongoceol, water passes through specialized channels in their bodies under the action of chaonocytes

Question 20

which of the following is not a component of the eukaryotic nucleus or its membrane: histones, nuclear pores, DNA, endoplasmic reticulum

Answer 20

endoplasmic reticulum

Question 21

in the process of exocytosis, molecules pass through these organelles in the following sequence

Answer 21

endoplasmic reticulum, golgi apparatus, secretory or transport vesicles, external plasma membrane

Question 22

Which of the following statements is correct?
a. Point mutations are always lethal to cells and organisms
b. Point mutations always result in changes in coded amino acids
c. Point mutations can sometimes produce changes in coded amino acids in proteins
d. Point mutations occur in proteins

Answer 22

point mutations can sometimes produce changes in coded amino acids in proteins

Question 23

which is NOT an autotroph:
photosynthetic alga
photosynthetic bacterium
symbiotic ciliate in rumen of sheep
tree

Answer 23

symbiotic ciliate in the rumen of a sheep

Question 24

mutualism is a form of symbiotic relationship in which

Answer 24

one organism lives in or on another organism, both benefit

Question 25

giardia parasites transit between hosts through

Answer 25

feacal-oral transmission, a cyst stage of parasite passes w feces of an infected host and new host infected by ingesting those cysts

Question 26

apicomplexa is a clade of single cell eukaryotes, the name apicomplexa refers to:

Answer 26

the presence in the cell of an apical complex that is used to invade host cells

Question 27

which of following displays radial symmetry; planarian, fish, hydra, haemonchus

Answer 27

hydra

Question 28

ruminant mammals lack enzymes for digesting cellulose from plant material, in order to derive nutrition they rely on

Answer 28

endosymbiotic ciliates and prokaryotes in the rumen able to digest cellulose

Question 29

amoebae move through their environment by means of

Answer 29

pseudopodia

Question 30

the anatomical plane that runs perpendicular to the longitudinal axis of the body or limb is the

Answer 30

transverse plane

Question 31

viruses should be considered alive because

Answer 31

they possess genes, replicate and evolve

Question 32

which of the following is NOT used to classify viruses into taxonomic groups: -type of nucleic acid -shape of capsid -envelope or lock of -replication -genome sequence/organization -pH, temp -type of disease caused by virus

Answer 32

type of disease caused by virus

Question 33

list principles of the modern cell theory

Answer 33

- all known living things made from cells - all cells arise from pre-existing cells - the cell is the basic structural and functional unit of all living things - cells contain heredity info which is passed from cell to cell during cell division - all cells have basically the same chemical composition - all energy flow of life occurs within cells

Question 34

outline major steps of serial endosymbiosis theory of origins of eukaryotes

Answer 34

- ancestral prokaryote cell underwent infoldings of plasma membrane; gave rise to endomembrane components including nucleus and endoplasmic reticulum - this cell then engulfed other bacterial cells that evolved into other organelles such as mitochondria - later engulfed photosynthetic bacteria that evolved to be chloroplast

Question 35

characteristics of metazoa

Answer 35

- multicellular eukaryotes - cell differentiation (different cells have different function) - cell-cell cooperation (symbiotic) - ingestive heterotrophs (gain nutrients from other organims) - motile - homeostasis (consistent body environment) - diploidy (meiosis at reproduction) - have embryonic stage

Question 36

Write a short account of how the African trypanosome Trypanosoma brucei directly and indirectly affect human populations in Africa.

Answer 36

African Trypanosoma directly affects the human population by causing Sleeping sickness in humans. This results in CNS diseases, coma, and death. It can also indirectly reduce the human population by causing Nagana disease in domestic animals. This causes a decline in productivity in meat, milk, and labor which lead to poverty and starvation

Question 37

describe the 3 ways animal may develop disease from fungi

Answer 37

-can produce a toxin that can be absorbed or ingested -can be pathogenic -produce hypersensitivity or allergy

Question 38

discuss how genetic variation can occur in bacteria (4 ways)

Answer 38

- mutation, - transformation (take up foreign DNA from environment), - conjugation (plasmid gene transfer), - transduction: gene transfer between cells by phage (virus)

Question 39

describe autotrophic

Answer 39

organism that can produce its own nutrients by producing energy from light, water, CO2 or other chemicals

Question 40

describe eukaryotes

Answer 40

group of organisms with eukaryotic cells, contain a mitochondria/ chloroplast another organelles bound by a plasma membrane, have DNA bound in nuclear envelope

Question 41

how do the agents of african trypanosomiasis avoid being killed by their host when they are in the blood stream? what is molecular mechanism

Answer 41

variant surface glycoproteins (thick dense protein coat) their VSG is not recognized by the host and they can go undetected by immune system, they can periodically switch switch to another active VSG in order to stay undetected

Question 42

what are two pieces of evidence for the endosymbiosis theory

Answer 42

mitochondria have their own DNA and genomic sequence shows similarity between mitochondria and some prokaryotes also endosymbiosis happens today!! (mixotricha paradoxa in termites)

Question 43

how do the following move a) giardia b) sperm cell of cattle c) antamoeba histolyca d) apicomplexan baesia e) mutualistic eukaryotes of rumen

Answer 43

a) 8-10 flagella b)a single posterior flagellum c) pseudopodia d) cytoskeletal elements beneath plasma membrane e) cilia

Question 44

describe the 3 morpholgies of fungi

Answer 44

1) multicellular filamentous fungi that form microscopic fruiting bodies such as mould 2) multicellular filamentous fungi that form macroscopic fruiting bodies such as mushrooms 3) single celled yeast

Question 45

describe using examples how commensal bacteria can cause opportunist infections

Answer 45

commensals can become pathogenic when they gain access to abnormal location, or infects a host with diminished immune status (immunosuppressed, disease, normal gut flora disturbed ie from meds etc) example us fusobacterium necrophorum commensal of the rumen but when transfers to liver of cattle becomes pathogenic and cause hepatic abscesses

Question 46

describe structure and function of bacterial cell wall

Answer 46

contains peptidoglycan, maintains cell shape, provide physical protection, prevents osmotic bursting gram positive: thick wall of peptidoglycan gram negative; thin wall of peptidoglycan and contains lipopolysaccharide (endotoxin)

Question 47

name characteristics of living organisms

Answer 47

-contain water, -composed of elements: C,O,H,N,P,S among other -all life is carbon based -all share common atomic and molecular theme

Question 48

which of the following is not a feature of the prokaryotic cell -presence of histones -ribosomes -DNA -cell wall

Answer 48

presence of histones

Question 49

what is the trophozoite stage of giradia

Answer 49

the active feeding stage of the life cycle of this parasite

Question 50

are apicomplexa exclusively intracellular

Answer 50

yes

Question 51

Which of the following statement is NOT an accepted theory of the origin of viruses? a) Viruses evolved from escaped pieces of host cell DNA such as plasmids or transposons b) Viruses evolved from ribosomal RNA in primordial time c) Viruses evolved from degenerate unicellular life forms d) Viruses evolved from complex molecules of protein and nucleic acid independently to the evolution of host cells

Answer 51

Viruses evolved from ribosomal RNA in primordial time

Question 52

what is NOT a component of viruses: capsid, capsule, envelope, nucleic acid

Answer 52

capsule

Question 53

from list below select all that apply to phylum cnidaria: bilateral symmetry radial symmetry triploblastic development diploblastic development trues tissues

Answer 53

radial symmetry, diploblastic development, true tissues

Question 54

heterotrophic organism is one that

Answer 54

sources energy from organic compounds

Question 55

what are the various physical and chemical characteristics of a microbe that contribute to its pathogenicity virulence factors pathogenicity principles fomites none of above

Answer 55

virulence factors

Question 56

how is the malaria parasite transmitted between humans bite of tick bite of mosquito through fecal contamination of food

Answer 56

bite of mosquito

Question 57

common method of reproduction in yeast is fusion budding fragmentation fission

Answer 57

budding

Question 58

which are following characteristics of life; select all that apply all known living entities composed of elements that include COHNPS all living entities contain water all known living organisms evolved from viruses and prions all known life is silicon based all known live is carbon based

Answer 58

all known living entities composed of elements that include COHNPS all living entities contain water all known life is carbon based

Question 59

single celled eukaryotes in which the cell possesses a single posterior flagellum belong to clade commonly called the

Answer 59

opisthokonts

Question 60

cells contain heredity info that is passed from cell to cell during ______

Answer 60

cell division

Question 61

true or false the apicomplexa use locomotory organelles called flagella to move through their environment

Answer 61

false Locomotion; no visible apparatus for locomotion; move by gliding motility, apical complex secretes organelles and molecules from anterior end, flow along body + cell cytoskeleton= movement Rely on flow of medium for most movement (ex blood flow)

Question 62

ciliates typically posses two nuclei, a micronucleus and a macronucleus

Answer 62

true

Question 63

list the characeristics of a metazoa

Answer 63

-cell cell differentiation -multicellular eukaryotes -cell cell cooperation -diploidy -have an embryonic stage -motile -ingestive heterotrophic -homeostasis

Question 64

Why is the disease African trypanosomiasis considered a One Health issue? In your answer note how the parasitic organism responsible for African trypanosomiasis causes disease in its hosts.

Answer 64

-able to express 1000s of distinct proteins called variant surface glycoproteins (VSGs) allows them to go undetected by the immune system, they can periodically switch switch to another active VSG in order to stay undetected one health issue as it harms humans directly and indirectly kills humans by causing sleeping sickness; gets in the bloodstream and invades CNS results in coma and death kills animals via nagana disease, kills millions of cows a year, decreases meat and milk production , protein shortages

Question 65

describe three differences between bacteria and fungi

Answer 65

prokaryotes vs eukaryotes binary fission vs budding/ sexual reproduction cell walls composed of chitin versus peptidoglycan motility

Question 66

describe conjugation

Answer 66

plasmid gene transfer via direct contact

Question 67

endosymbiosis theory

Answer 67

Cell membrane infolded in a bacterial cells This infolded membrane eventually surrounded the nuclear material This advanced cell w endo-membranes engulfed the other bacterial cells These internal cells eventually became organelles-mitochondria Other cells engulfed (ex photosynthetic bacteria) other cells became other organelles like chloroplasts

Question 68

how do virus particles leave the host cell once they are assembled

Answer 68

lysis of cell causing cell death, often cause disease