Exam Practice Questions Flashcards
Which of the following statements about auxin, a plant hormone, is NOT true?
a. It can trigger expansion of the cell by acidifying the cell wall space
b. It can trigger seed germination
c. It is required for root gravitropism
d. It shows polar transport in the xylem transpiration system
e. It can prevent axillary buds from expanding
b. It can trigger seed germination
Which molecule does NOT absorb visible light?
a. ATP
b. Chlorophyll a
c. Phytochrome
d. Chlorophyll b
e. Carotenoids
a. ATP
Meristems contain dividing cells and…
a. Are found only in above-ground parts of the plant
b. Can contribute to lateral growth
c. Can be found in developing leaves
d. Are only found in the bark in perennials
e. Are only found in the root and shoot apex
b. Can contribute to lateral growth
Apical dominance involves…
Auxin and cytokinin
Which of the following statements is NOT true about plant cell walls?
a. Cell walls contain cellulose and hemicellulose
b. Cell walls are hydrophilic and contain water
c. Cell walls can be reinforced with lignin
d. Cell walls form impermeable barriers to molecules of all sizes
e. The cell wall can expand at early developmental stages
d. Cell walls form impermeable barriers to molecules of all sizes
Seed germination is a carefully orchestrated process. It can be summarized like this:
The embryo releases gibberellins into the seed and starts the synthesis of starch degrading enzymes.
The spindle-shaped cells that transport water in plants are called…
Tracheids
Which of the following proteins is instrumental in moving protons across the thylakoid membrane during photosynthesis?
a. Cytochrome complex
b. P680
c. ATPase/proton pump
d. ferredoxin
e. NADP reductase
a. Cytochrome complex
Which of the following types of substances or proteins are least likely to be a defence of plants against leaf-eating herbivores?
a. Cell wall-digesting enzymes
b. Phytoecdysone (steroid hormone mimic)
c. Alkaloids, phytochemicals with strong neurological effects
d. Cyanide produced by plant cells
e. Protease inhibitors and oxidative enzymes
a. Cell wall-digesting enzymes
The light-independent reactions…
Occur in the light or in the dark?
Why?
Occur in the light as they need energy from the light-dependant reactions
Which of the following plant growth regulators does Agrobacterium manipulate in order to generate a crown gall tumour?
Auxin and cytokinin
To induce bending of the root tip downwards during gravitropism, auxin…
Moves to the lower part of the root tip.
True or false: Phloem sieve tubes
- Anucleate
- Dead at maturity
- May conduct amino acids
- Conduct sugars and other nutrients
- Contain cytoplasm
All true, except that they are ALIVE at maturity
Does phloem transport require energy?
In many plants, sugar movement into the phloem requires active transport because sucrose is more concentrated in sieve-tube elements and companion cells than in mesophyll.
The Calvin cycle and light-independent reactions take place in the…
Stroma
