plants lab quiz

Question 1

xylem

Answer 1

• vascular tissue reponsible for transport of water and dissolved substances
• forms continuous pathway through roots, stem, and leaves
• cells have thick cell walls and are dead at maturity
• thicker-walled xylem strengthened by presence of lignin, important for support

Question 2

phloem

Answer 2

• vascular tissue responsible for transport of organic materials (ex: carbohydrates and amino acids)
• transports from organic molecules from leaves to stem and roots for storage; or to growing points of cell for immediate use
• cells are thin-walled with cytoplasm but lack nuclei
• have special companion cells with nuclei next to conducting cells

Question 3

air space

Answer 3

intercellular gaps filled with gas (CO2, O2) within the spongy mesophyll

Question 4

cuticle

Answer 4

waxy, water-repelling layer on top and bottom surfaces of a leaf

• keeps leaf from drying out
• protects against bacteria, insects, fungi
• secreted by the epidermis

Question 5

guard cell

Answer 5

one of a pair of sausage-shaped cells surrounding a stoma

- change shape, causing stoma to open and close

Question 6

lower epidermis

Answer 6

waxy skin on the underside of a leaf, one cell thick, keeps leaf from drying out - outermost cells

Question 7

upper epidermis

Answer 7

protective, outer layer of cells on upper surface of leaf, one cell thick, secreted by waxy cuticle, contains some guard cells

Question 8

mesophyll

Answer 8

chlorophyll-containing leaf tissue located between the upper and lower epidermis; convert sunlight into usable chemical energy for plant
- two types: palisade, spongy

Question 9

palisade mesophyll

Answer 9

layer of elongated cells located under the upper epidermis

- contain most of leaf’s chlorophyll, converting sunlight into energy for plant

Question 10

spongy mesophyll

Answer 10

layer below the palisade mesophyll, has irregularly shaped cells with many air spaces between the cells
- cells contain some chlorophyll, cells communicate with guard cells, causing them to open and close, depending on concentration of gases

Question 11

stoma

Answer 11

pore inleaf where water vapour and other gases leave and enter the plat; formed by two guard cells that regulate opening/closing of pore, mainly found on bottom of leaf

Question 12

vein

Answer 12

provide support for leaf and transport both water and minerals (xylem) and food energy (phloem) through leaf and to rest of the plant

Question 13

mesophytes

Answer 13

plants that thrive in average conditions

ex: maple trees, lilac bushes, tulips

Question 14

xerophytes

Answer 14

plants that thrive in desert like conditions, with less water, more sun and hotter temperatures
ex: cactus, aloe vera

Question 15

hydrophytes

Answer 15

plants that grow (float) on the surface of ponds and lakes

ex: water lily

Question 16

roots

Answer 16

• responsible for absorbing and conducting water and mineral nutrients
• anchor the plant in place, providing structural support and resistance

Question 17

stems

Answer 17

allows plant to push itself up against gravity, contain vascular tissue to conduct water and dissolved minerals up or down in the plant, provides support allowing plant to grow upwards, contains epidermal tissue to protect against pathogens

Question 18

nodes

Answer 18

point where leaves attach to stem

Question 19

internodes

Answer 19

stretches of stem seperating nodes

Question 20

leaves

Answer 20

primary function is photosynthesis (production of organic compounds)

Question 21

two types of plant tissue

Answer 21

meristematic and permanent

Question 22

meristematic tissue

Answer 22

composed of immature cells actively dividing, found where plant is growing: root/stem tips, flower buds, embryos (seeds)

Question 23

permanent plant tissue

Answer 23

three categories: surface, ground and vascular

Question 24

surface tissues (permanent)

Answer 24

protective outer covering of plant body, cells are flat and interlock like puzzle pieces, outer walls thicker than inner walls and impregnanted with cutin (waxy substance)

Question 25

ground tissues (permanent)

Answer 25

parenchyma, collenchyma, sclerenchyma (make up the bulk of plant organs)

Question 26

parenchyma

Answer 26

predominant ground tissue cell, thin/flexible cells walls, unspecialized, contain plastids
- function: photosynthesis, nutrient storage, give support and shape to plant when filled with water, repair damaged tissues

Question 27

collenchyma

Answer 27

thick cell walls, strong (additional cellulose and pectin), grouped into bundles of cells, function: support of plants

Question 28

sclerenchyma

Answer 28

thick cell walls (hardened by lignin), at maturity cells are dead, important for support of plant, used for linen threads (weaving, sewing, paper); wood coconut shells and apple cores made of this

Question 29

vascular tissues

Answer 29

xykem, phloem, air space, cuticle, guard cell, stoma, lower epidermis, upper epidermis, mesophyll (palisade and spongy), vein