Biolab 5: Woody Stem and Root Structure

Question 1

terminal bud

Answer 1

occurs at the tip of a twig and is responsible for its growth in length

Question 2

bud scales

Answer 2

modified leaves, they enclose and potect the embryonic leaves and apical meristem within the bud

Question 3

terminal bud scale

Answer 3

band of closely grouped scars (rings) encircling the twig

Question 4

season of growth

Answer 4

the scars are those left after the bud scales fell off, indicate a season of growth

Question 5

leaf scar

Answer 5

left on the twig where the petiole or base of the leaf was once attached

Question 6

vascular bundle scars

Answer 6

scars of the broken ends of hte bascualr strands that passed between leaf and stem

Question 7

Node

Answer 7

the region on a twig where one or more leaves are borne

Question 8

internode

Answer 8

the portion of the twig between any two successive nodes

Question 9

Lateral bud

Answer 9

bud occurs on the side of the twig

Question 10

axillary bud

Answer 10

when leaf is present, this bud is in the axil between the petiole and the stem

Question 11

lenticels

Answer 11

raised areas of loose cork

Question 12

gymnosperm stem

Answer 12

like pines, hemlocks, spruce, they have no vessels or sieve tubes
lack fibre and have little parenchyma

Question 13

tracheid

Answer 13

elongate, slender, needle-like cell with long tapering end walls, cell is dead

Question 14

protoplast

Answer 14

living component of a plant cell

Question 15

ray parenchyma cell

Answer 15

parenchyma cell with living protoplast that stores food, it borders the tracheids at right angles and connect with them through pits

Question 16

secondary xylem

Answer 16

the wood

Question 17

annual rings or growth rings

Answer 17

each one represents one years formation of xylem

Question 18

earlywood or spirngwood

Answer 18

the larger tracheids were formed early in the growing season and are known as early wood or spring wood

Question 19

latewood or summerwood

Answer 19

smaller tracheids formed later in the growing season, are known as latewood or summerwood

Question 20

secondary wall

Answer 20

that give cells a rigid reinforcement , encrusted with a material known as lignin

Question 21

rays

Answer 21

each ray is a sheet of parenchyma cells that extends vertically in the stem

Question 22

pith

Answer 22

centre of the stem, within the innermost growth ring, the central core is called the pith

Question 23

resin canals or resin ducts

Answer 23

extend lenghtwise in the stem

Question 24

vascular cambium

Answer 24

increase the girth of the stem by forming later after layer of xylem and phloem around the original primary cylinder

Question 25

cambial zone

Answer 25

band of unexpanded meristmeatic cells , about 4 to 8 cells wide, consists of one vascular cambium

Question 26

phloem initials

Answer 26

daughter cells on the outside of the cambial and develop into phloem cells

Question 27

xylem initials

Answer 27

inside of the cambial layer, and develop into xylem cells

Question 28

bark

Answer 28

defined as all those tissues that lie outside of the vascualr cambium

Question 29

outer bark

Answer 29

periderm

Question 30

inner bark

Answer 30

phloem

Question 31

sieve cells

Answer 31

vertically elongate cells which in the cross section are the angular, thing-walled cells in orderly rows, conduct the products of photos. to actively growing buds and young leaves

Question 32

phloem parenchyma cells

Answer 32

round, thing walled cells filled with dark coloured material

Question 33

ray parenchyma cells

Answer 33

elongated cells with prominent nuclei

Question 34

cortex

Answer 34

primary tissue, produced by apical meristem

Question 35

cork cambium

Answer 35

produces cork cells towards teh outside of the stem adn thick walled parenchyma cells

Question 36

suberin

Answer 36

cork cell walls contain suberin, which is a fatty material that makes them impervious to water