Ch 6 Flashcards Preview

Plant Biology > Ch 6 > Flashcards

Flashcards in Ch 6 Deck (35):
1

Leaf blade (Lamina)

the broad, expanded part of a leaf; not the petiole; flat, light-harvesting portion

2

Petiole

stalk that holds the blade out into the light

3

Sessile leaf base

leaves are small or very long and narrow, self-shading is not a problem

4

Sheathing leaf base

the leaf base wraps around the stem

5

Simple leaf

has a blade of just one part

6

Compound leaf

has a blade divided into into several parts

7

Leaflets

many small blades

8

Petiolule

the stalk that attaches a leaflet to the rachis of a compound

9

Rachis

the extension of the petiole in a compound leaf; all leaflets are attached to the rachis

10

Veins

bundles of vascular tissue; distribute water from the stem to the leaf; collects sugars produced by photosynthesis and carries them to the stem for use or storage

11

Reticulate Venation

netlike pattern of veins in a leaf, found primarily in leaves of dicots (broadleaf plants)

12

Parallel Venation

almost exclusively in monocot leaves, a pattern in which all veins run approximately parallel to each other, either from the base of the leaf to its tip or from the midrib to the margin

13

Abscission zone

the region at the base of an organ, such as a leaf or fruit, in which cells die and tear, permitting the organ to fall cleanly away from the stem with a minimum of damage

14

Leaf scar

the region on a stem where a leaf was attached prior to abscission

15

Epidermis

outermost layer of the plant primary body, covering leaves, flower parts, young stems and roots

16

Transpiration

loss of water vapor through the epidermis

17

Mesophyll

all tissues of a leaf except the epidermis

18

Palisade parenchyma

any part of leaf mesophyll in which the cells are elongate and aligned parallel to each other

19

Spongy mesophyll

any part of leaf mesophyll in which the cells are not aligned parallel to each other and are separated by large intercellular spaces

20

Mid-rib veins

the large, central vascular bundle of a leaf

21

Lateral veins

the major, large vascular bundles of a leaf, which are attached to the midrib or the petiole; larger than minor veins

22

Minor veins

smallest veins of a leaf, branching off lateral veins; there is no criterion that strictly distinguishes between minor and lateral veins

23

Bundle sheath

a set of cells, which may be parenchyma, collencyma, or sclerenchyma, that encases some or all of the vascular bundles of a leaf

24

Bundle Sheath Extension

a set of cells, usually fibers, that extends from the bundle sheath to the upper or lower (or both) epidermis of a leaf

25

Leaf Traces

vascular bundle that extends from the stem vascular bundles through the cortex and enters a leaf

26

Stipules

small flaps of tissue located at the base of a leaf, near its attachment to the stem; stipules may range from quite leaflike to small and inconspiculous

27

Leaf primordium

an extremely early stage in leaf development, when the leaf exists only as a pronounced bulging of the shoot apical meristem

28

Succulent leaves

permits plants to survive in the desert; thick and fleshy leaves which reduces surface-to-volume ratio and favors water conservation; consequence of reducing the capacity for carbon dioxide uptake

29

Sclerophyllous foliage leaves

must produce more sugars by photosynthesis than are used in their own construction and metabolism or the plant would lose energy every time it produced a leaf; leaves are soft, flexible, edible and less sclerenchyma

30

Leaves of conifers

leaves are sclerophylls; they have a thick cuticle, their epidermis and hypodermis cells have thick walls; always simple and only have a few forms; needle-shaped leaves

31

Bud scales

small specialized leaf, usually waxy or corky, that protects an unopened bud; protection; small and rarely compound

32

Spines

modified leaves of axillary buds; protection; ie cacti; no blade and are needle shaped

33

Tendrils

modified leaves; grow indefinitely and contain cells capable of sensing contact with an object; tendril touches something that side stops gorwing and the other side continues to elongate

34

Leaves with Kranz Anatomy

in C4 plants; have bundle sheaths composed of large chlorophyllous cells; ring of mesophylls cells surround the sheath; adapted to arid env

35

Insect traps

insectivory in habitats poor in nitrates and ammonia; trap leaves are either active traps that move during capture or passive traps incapable of moving