Plant Control Systems and Fungi

Question 1

Why are lateral buds often inhibited from sprouting even though a stem may be actively elongating?

a) The cells of lateral buds are more sensitive to auxin than stem cells
b) Lateral buds are high in abscisic acid that prevents elongation.
c) Lateral buds are low in gibberellins.
d) Stem cells lack receptors for auxin.
e) Stem cells can overcome auxin inhibition with high levels of gibberellins.

Answer 1

The cells of lateral buds are more sensitive to auxin than stem cells

Question 2

The detector of light during de-etiolation (greening) of a tomato plant is (are)

a) carotenoids.
b) xanthophylls.
c) phytochrome.
d) chlorophyll.
e) auxin.

Answer 2

c) phytochrome

Question 3

A plant seedling bends toward sunlight because

a) auxin is destroyed more quickly on the dark side of the stem
b) auxin migrates tot he lower part of the stem due to gravity
c) gibberellins produced at the stem tip cause phototropism
d) there is more auxin on the light side of the stem
e) auxin is found in greatest abundance on the dark side of the stem

Answer 3

e) auxin is found in greatest abundance on the dark side of the stem

Question 4

Which of the following plant growth responses is primarily due to the action of auxins?

a) cell division
b) leaf abscission
c) the detection of photoperiod
d) cell elongation
e) fruit development

Answer 4

d) cell elongation

Question 5

The plant hormone involved in aging and ripening of fruit is

a) abscisic acid.
b) auxin.
c) ethylene.
d) gibberellin.
e) florigen.

Answer 5

c) ethylene.

Question 6

Fungi differ from other heterotrophic organisms in which way?
Question 6 options:

a) They have only a few very specific yet weak enzymes for digestion.
b) They secrete enzymes on the outside of a food source, and then absorb nutrients from both living and non-living cells.
c) They ingest only microscopic organisms.
d) Their enzymes can break down only simple molecules.
e) They make their own food if they cannot obtain sufficient food by ingestion.

Answer 6

b) They secrete enzymes on the outside of a food source, and then absorb nutrients from both living and non-living cells.

Question 7

The following statements about mycorrizhae are true, with the exception of

a) in reforestation, seedlings are innoculated with mycorrhizae to enhance their growth.
b) nutrients are transferred between different trees by mycorrhizae.
c) almost all vascular plants have mycorrhizae.
d) arbuscular mycorrhizae is parasitic on some species of plants.

Answer 7

d) arbuscular mycorrhizae is parasitic on some species of plants

Question 8

Lichens are symbiotic associations of fungi and

a) green algae
b) mosses
c) cyanobacteria
d) three of these responses are correct
e) two of these responses are correct

Answer 8

e) two of these responses are correct (a, c)

Question 9

If all fungi in an environment that perform decomposition were to suddenly die, then which group of organisms should benefit most, due to the fact that their fungal competitors have been removed?

a) mutualistic fungi
b) prokaryotes
c) protists
d) plants
e) animals

Answer 9

b) prokaryotes

Question 10

Plasmogamy can directly result in which of the following?
1. cells with a single haploid nucleus
2. heterokaryotic cells
3. dikaryotic cells
4. cells with two diploid nuclei

a) 1 or 2
b) 3 or 4
c) 1 or 3
d) 2 or 4
e) 2 or 3

Answer 10

e) 2 or 3

Question 11

Axillary buds

a) have dormant meristematic cells
b) do not form a vascular connection with the primary shoot
c) grow immediately into shoot branches
d) are initiated by the cork cambium
e) are composed of a series of internodes lack nodes

Answer 11

a) have dormant meristematic cells

Question 12

Plants contain meristems whose major function is to

a) attract pollinators
b) produce flowers
c) photosynthesize
d) produce more cells
e) absorb ions

Answer 12

d) produce more cells

Question 13

Which structure or compartment is not part of the plant’s apoplast?

a) the lumen of a sieve tube
b) the cell wall of a transfer cell
c) the lumen of a xylem vessel
d) the cell wall of a mesophyll cell
e) the cell wall of a root hair

Answer 13

a) the lumen of a sieve tube

Question 14

Pine seedlings grown in sterile potting soil grow much more slowly than seedlings grown in soil from the area where the seeds were collected. This is most likely because

a) the sterilization process kills the root hairs as they emerge from the seedling.
b) the normal symbiotic fungi are not present in the sterilized soil.
c) sterilization removes essential nutrients from the soil.
d) water and mineral uptake are faster when mycorrhizae are present.
e) B and D.

Answer 14

e) B and D

Question 15

Which taxon is essentially equivalent to the “embryophytes”?

a) Bryophyta
b) Viridiplantae
c) Plantae
d) Pterophyta
e) Charophycea

Answer 15

c) Plantae

Question 16

If a fern gametophyte is a hermaphrodite (that is, has both male and female gametangia on the same plant), then it

a) has antheridia and archegonia combined into a single sex organ
b) is actually not a fern, because fern gametophytes are always either male or female
c) belongs to a species that is homosporous
d) has lost the need for a sporophyte generation
e) must be diploid

Answer 16

c) belongs to a species that is homosporous

Question 17

In addition to seeds, which of the following characteristics are unique to the seed-producing plants?

a) use of air currents as a dispersal agent
b) megaphylls
c) lignin present in cell walls
d) sporopollenin
e) pollen

Answer 17

e) pollen

Question 18

Which group is noted for the independence of gametophyte and sporophyte generations from each other?

a) angiosperms
b) ferns
c) charophytes
d) mosses, hornworts, and liverworts
e) gymnosperms

Answer 18

b) ferns

Question 19

Why are C4 plants able to photosynthesize with no apparent photorespiration?

a) They use PEP carboxylase to initially fix CO2
b) They are adapted to cold, wet climates
c) They exclude oxygen from their tissues
d) They conserve water more efficiently
e) They do not participate in the Calvin cycle

Answer 19

a) They use PEP carboxylase to initially fix CO2

Question 20

Where is the Calvin cycle located in a C4 plant?

a) bundle sheath cells
b) mesophyll cells
c) stomata
d) stems
e) the chloroplasts in leaves

Answer 20

a) bundle sheath cells

Question 21

If protein synthesis was blocked in etiolated cells, what would be necessary for the “greening” of these cells?

Answer 21

Post-translational modification of existing proteins

Question 22

Why might animal hormones function differently than plant hormones?

Answer 22

Plants are much more variable in their morphology and development than animals

Question 23

Which of the following plant hormones would most likely be found in high concentrations in a mature, slightly overripe fruit?

Answer 23

abscisic acid and ethylene

Question 24

Charles and Francis Darwin discovered that

a) auxin is responsible for phototropic curvature
b) auxin can pass through agar
c) light destroys auxin
d) light is perceived by the tips of coleoptiles
e) red light is most effective in shoot phototropism

Question 25

What is the probable role of salicylic acid in the defense responses of plants?

a) to destroy pathogens directly
b) to activate systemic acquired resistance of plants
c) to close stomata, thus preventing the entry of pathogens
d) to activate heat-shock proteins
e) to sacrifice infected tissues by hydrolyzing cells

Answer 25

b) to activate systemic acquired resistance of plants

Question 26

Which of these paired fungal structures are structurally and functionally most alike?

a) sporangia and hyphae
b) zoospores and mycelia
c) haustoria and arbuscules
d) conidia and basidiocarps
e) soredia and gills

Answer 26

c) haustoria and arbuscules

Question 27

The vegetative (nutritionally active) bodies of most fungi are

a) referred to as a mycelium
b) usually underground
c) composed of hyphae
d) three of these answers are correct
e) two of these answers are correct

Answer 27

d) three of these answers are correct

Question 28

What is the importance of a high surface area to volume ratio of mycelia?

Answer 28

Allows for efficient absorption of nutrients

Question 29

Fungi differ from other heterotrophic organisms in which way?

a) They have only a few very specific yet weak enzymes for digestion.
b) They secrete enzymes on the outside of a food source, and then absorb nutrients from both living and non-living cells.
c) They ingest only microscopic organisms.
d) Their enzymes can break down only simple molecules.
e) They make their own food if they cannot obtain sufficient food by ingestion.

Answer 29

b) They secrete enzymes on the outside of a food source, and then absorb nutrients from both living and non-living cells

Question 30

If all fungi in an environment that perform decomposition were to suddenly die, then which group of organisms should benefit most, due to the fact that their fungal competitors have been removed?

a) mutualistic fungi
b) prokaryotes
c) protists
d) plants
e) animals

Answer 30

b) prokaryotes

Question 31

Which part of a plant absorbs most of the water and minerals taken up from the soil?

a) the thick parts of the roots near the base of the stem
b) storage roots
c) sections of the root that have secondary xylem
d) taproots
e) root hairs

Answer 31

e) root hairs

Question 32

The water lost during transpiration is a side effect of the plant’s exchange of gases. However, the plant derives some benefit from this water loss in the form of

a) mineral transport
b) increased growth
c) only evaporative cooling and mineral transport
d) evaporative cooling
e) increased turgor

Answer 32

c) evaporative cooling and mineral transport

Question 33

Which of the following is responsible for the cohesion of water molecules?

a) low concentrations of charged solutes in the fluid
b) hydrogen bonds between the oxygen atoms of a water molecule and cellulose in a vessel cell
c) covalent bonds between the oxygen atom of one water molecule and a hydrogen atom of another water molecule
d) covalent bonds between the hydrogen atoms of two adjacent water molecules
e) hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another water molecule

Answer 33

e) hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another water molecule

Question 34

Which of the following structures are in the gametophyte generation of a moss?

a) egg, sperm, zygote, sporangium
b) buds, leaves, spores, rhizoids
c) antheridia, archegonia, egg, sperm
d) foot, seta, spores, sporangium

Answer 34

c) antheridia, archegonia, egg, sperm

Question 35

The functional role of sporopollenin is primarily to

a) comprise spore surface structures that catch the wind and assist in spore dispersal
b) reduce dehydration
c) provide nutrients to spores
d) make spores less dense and able to disperse more readily
e) repel toxic chemicals

Answer 35

b) reduce dehydration

Question 36

Which of the following flower parts develops into the pulp of a fleshy fruit?

Answer 36

ovary

Question 37

Which of the following structures in the life cycle of a pine are haploid?

a) mature sporophyte, ovulate cone, pollen cone, female gametophyte
b) megasporocyte, megasporangium, megaspore, female gametophyte
c) pollen grains, megaspore, female gametophyte, egg nucleus
d) new sporophyte, pollen cone, pollen grains, microsporocytes

Answer 37

c) pollen grains, megaspore, female gametophyte, egg nucleus

Question 38

In the process of carbon fixation, RuBP attaches a CO2 to produce a six-carbon molecule, which is then split to produce two molecules of 3-phosphoglycerate. After phosphorylation and reduction produces glyceraldehyde 3-phosphate (G3P), what more needs to happen to complete the Calvin cycle?

a) inactivation of RuBP carboxylase enzyme
b) regeneration of ATP from ADP
c) regeneration of NADP+
d) addition of a pair of electrons from NADPH
e) regeneration of RuBP

Answer 38

e) regeneration of RuBP