Cellular Structure in Plants

Question 1

5 types of cells in plants

Answer 1

Parenchyma
Collenchyma
Sclerenchyma
Water-conducting cells of the xylem
Sugar-conducting cells of the phloem

Question 2

What is ground tissue composed of

Answer 2

Parenchyma
Collenchyma
Sclerenchyma

Question 3

Parenchyma cells in ground tissue

Answer 3

have thin and flexible primary walls
Large central vacuole
Lack secondary walls
Are the least specialized
Perform the most metabolic functions
Retain the ability to divide and differentiate

Question 4

Metabolic functions of parenchyma ground tissue cells

Answer 4

store nutrients

Photosynthesize

Question 5

Collenchyma ground tissue cells

Answer 5

grouped in strands and help support young parts of the plant shoot
Have thicker and uneven cell walls
They lack secondary walls
These cells provide flexible support without restraining growth
Strings in a celery stalk

Question 6

Sclerenchyma ground tissue cells

Answer 6

rigid because of thick secondary walls strengthened with lignin
dead at functional maturity

Question 7

Two types of sclerenchyma cells

Answer 7

sclereids and fibers

Question 8

sclereids

Answer 8

short and irregular in shape and have thick lignified secondary walls
source of hardness in nutshells and seed coats

Question 9

Fibers

Answer 9

long and slender and arranged in threads

Question 10

Vascular Tissue cells

Answer 10

Xylem and Phloem

Question 11

Tracheids

Answer 11

Found in all vascular plants
Tubular, elongated and dead
Water transfers via pits in the tracheids

Question 12

Vessel elements

Answer 12

large diameter and shorter
Aligned end-to-end to form vessels
End walls have perforation plates

Question 13

Phloem cells

Answer 13

Sieve-tube elements
Sieve plates
Companion cell

Question 14

Sieve-tube elements

Answer 14

Alive at functional maturity
They lack organelles, including nucleus
Allows sugars to flow more easily

Question 15

Sieve plates

Answer 15

The porous end walls that allow fluid to flow between cells along the sieve tube

Question 16

Companion cell

Answer 16

One for each sieve-tube element

Nucleus and ribosomes serve both cell

Question 17

Cell Growth

Answer 17

Indeterminate growth, Determinate growth, Annuals, Biennials, and Perennials

Question 18

Indeterminate growth

Answer 18

growing throughout and organism’s life

Question 19

Determinate growth

Answer 19

some plant organs cease to grow at a certain size

Question 20

Annuals

Answer 20

Complete their life cycle in a year or less

Question 21

Biennials

Answer 21

Require two growing seasons

Question 22

Perennials

Answer 22

Live for many years

Question 23

Meristems

Answer 23

Perpetually embryonic tissue
Maintains indeterminate growth
Functionally similar to animal stem cells

Question 24

Apical meristems

Answer 24

located at the tips of roots and shoots and at the axillary buds of shoots

Question 25

Primary growth

Answer 25

occurs when apical meristems elongate shoots and roots

Question 26

Secondary growth

Answer 26

lateral meristems add thickness to woody plants. Involves two lateral meristems

Question 27

Two kinds of lateral meristems

Answer 27

vascular cambium and cork cambium

Question 28

vascular cambium

Answer 28

adds layers of vascular tissue called secondary xylem (wood) and secondary phloem

Question 29

Cork cambium

Answer 29

replaces the epidermis with periderm, which is thicker and tougher

Question 30

Tree rings

Answer 30

visible where late and early wood meet, and can be used to estimate a tree's age

Question 31

Dendrochronology

Answer 31

the analysis of tree ring growth patterns, and can be used to study past climate change

Question 32

What is the vascular cambium made of

Answer 32

a cylinder of meristematic cells one cell layer thick

Question 33

what does the vascular cambium develop from

Answer 33

undifferentiated parenchyma cells

Question 34

what does the secondary xylem accumulate as

Answer 34

wood, and consists of tracheas, vessel elements (only in angiosperms), and fibers

Question 35

Early wood

Answer 35

formed in the spring, has thin cell walls to maximize water delivery

Question 36

late wood

Answer 36

formed in late summer, has thick-walled cells and contributes more to stem support

Question 37

As a tree or woody shrub ages,

Answer 37

the older layers of secondary xylem, the heartwood, no longer transport water and minerals Outer layers, known as sapwood, still transport materials through the xylem Older secondary phloem sloughs off and does not accumulate

Question 38

Xylem Cells

Answer 38

Tracheids and Vessel elements