BOT3015 CH4 EXAM QUESTIONS AND ACCURATE ANSWERS
What is the function of phloem in plants?
A. Food-conduction
B. water conduction
C. Gas conduction
Food-conduction
The principal conductive cells of phloem are elongated __________ __________ cells.
Intimately associated with them are narrower, more tapered __________ cells.
sieve tube; companion
A longitudinal series of sieve-tube cells arranged end to end is called a __________.
sieve tube
The end cell walls of sieve-tube members contain many small pores through which the
cytoplasms of adjacent cells connect. These porous regions are called __________
__________.
sieve plates
True or false: Matures sieve-tube members are alive, even though they do not contain
nuclei.
True
What is the function of callose when a cell is injured by an insect, such as an aphid?
A. It seals off the nearest sieve plate, preventing leaking of fluid from the sieve tube.
, B. It is hydrolyzed into glucose, providing energy for the cell so it can rapidly
regenerate.
C. It acts as an insecticide naturally.
It seals off the nearest sieve plate, preventing leaking of fluid from the sieve tube.
Which of the following characterizes the role of companion cells in phloem tissue?
A. They have a close relationship with their associated sieve-tube members and help
them in conducting foods.
B. They are always dividing in order to replace dead sieve-tube members.
C. They act like fibers in supporting phloem due to their thickened cell walls.
They have a close relationship with their associated sieve-tube members and help them
in conducting foods.
In conifers and ferns, sieve cells have __________ cells, which are the equivalent to
companion cells.
albuminous
The outermost cell layer of young plant organs for example, leaves is called the
__________.
epidermis
The aerial roots of orchids are called __________ roots. These have a multiple-layered
__________, the outermost cells of which form a sponge (that is, they absorb water).
velamen; epidermis
Which of the following are true of the cuticle? (Select all that apply.)
A. It gives strength to stems and leaves.
B. It is highly resistant to pathogens, including bacteria and viruses.
What is the function of phloem in plants?
A. Food-conduction
B. water conduction
C. Gas conduction
Food-conduction
The principal conductive cells of phloem are elongated __________ __________ cells.
Intimately associated with them are narrower, more tapered __________ cells.
sieve tube; companion
A longitudinal series of sieve-tube cells arranged end to end is called a __________.
sieve tube
The end cell walls of sieve-tube members contain many small pores through which the
cytoplasms of adjacent cells connect. These porous regions are called __________
__________.
sieve plates
True or false: Matures sieve-tube members are alive, even though they do not contain
nuclei.
True
What is the function of callose when a cell is injured by an insect, such as an aphid?
A. It seals off the nearest sieve plate, preventing leaking of fluid from the sieve tube.
, B. It is hydrolyzed into glucose, providing energy for the cell so it can rapidly
regenerate.
C. It acts as an insecticide naturally.
It seals off the nearest sieve plate, preventing leaking of fluid from the sieve tube.
Which of the following characterizes the role of companion cells in phloem tissue?
A. They have a close relationship with their associated sieve-tube members and help
them in conducting foods.
B. They are always dividing in order to replace dead sieve-tube members.
C. They act like fibers in supporting phloem due to their thickened cell walls.
They have a close relationship with their associated sieve-tube members and help them
in conducting foods.
In conifers and ferns, sieve cells have __________ cells, which are the equivalent to
companion cells.
albuminous
The outermost cell layer of young plant organs for example, leaves is called the
__________.
epidermis
The aerial roots of orchids are called __________ roots. These have a multiple-layered
__________, the outermost cells of which form a sponge (that is, they absorb water).
velamen; epidermis
Which of the following are true of the cuticle? (Select all that apply.)
A. It gives strength to stems and leaves.
B. It is highly resistant to pathogens, including bacteria and viruses.
