6-Leaves

Question 1

Leaves are formed by the…

Answer 1

Apical Meristem

Question 2

Leaves grow at nodes from…

Answer 2

Leaf Primordia

Question 3

What defines a leaf?

Answer 3

Auxiliary Bud

Question 4

Two things that are NOT leave?

Answer 4

Enations + Microphylls

Question 5

What is an enation?

Answer 5

-An outgrowth; increases surface area for photosynthesis
-Using no vascular tissue
-Epidermic

Question 6

What is a microphyll?

Answer 6

-small leaves with a SINGLE
strand of vascular tissue
associated with protostele
-NO
leaf gap

Question 7

What is a macrophyll?

Answer 7

True LEAF!
veins, associated
with a leaf gap or leaf
trace gap

Question 8

What is a leaf gap?

Answer 8

Specialized siphonosteles

Question 9

What is a leaf trace gap?

Answer 9

Eustele

Question 10

Leaf vs. Leaflet

Answer 10

extend from stem in VARIOUS planes vs ONE plane/flat (leaflets)

Question 11

What is a lamina?

Answer 11

Leaf blade

Question 12

What is a petiole?

Answer 12

Leaf stem

Question 13

What is a sessile?

Answer 13

Leaf blade attaches directly to stem - no petiole (stem)

Question 14

What is a sheath?

Answer 14

leaves with the leaf base surrounding the stem (in some grasses)

Question 15

What is a stipule? *in macrophylls

Answer 15

flap of tissue surrounding petiole (stem); at BASE of leaf; functions as protection when leaf is small and delicate

Question 16

What are the two leaf shapes?

Answer 16

Simple (blade not divided) + Compound (with leaflets)

Question 17

What are the TWO divisions of a compound leaf?

Answer 17

Pinnate
(leaflets arise from rachis)

Palmate
(no rachis)

rachis=main stem

Question 18

Heteroblastic Development *in megaphylls

Answer 18

leaf shape (form) changes during PLANT DEVELOPMENT (e.g. eucalyptus, ivy, juniper)

Question 19

Heterophylly Development *in megaphylls

Answer 19

leaf shape changes, depending on ENVIRONMENT (e.g. aquatic buttercup)

Question 20

Phyllotaxy (leaf arrangement) determines..

Answer 20

branch arrangement

Question 21

The 3 Types of megaphylls…

Answer 21

Mesophytes → requires a moist area

Xerophytes → adapted to dry environment

Hydrophytes → adapted to a very wet environment (may be submerged)

Question 22

The epidermis & cuticle in megaphylls helps reduce…

Answer 22

water loss!

Question 23

Stomata & guard cells in megaphylls occur more..

Answer 23

on LOWER leaf surface
(keep dirt out/avoid evaporation)

Question 24

What are hydathodes? (on epidermis of some species)

Answer 24

-Pores in leaf surface (often modified stomata that lack the ability to open and close)
-Allow leakage of water droplets = guttation

Question 25

What is guttation?

Answer 25

Allow leakage of water droplets *not dew, liquid coming off grass; often modified STOMATA. If there's positive pressure inside plant, will leak out of porous tissue coming out of vein

Question 26

What are trichomes? What is their function?

Answer 26

modified epidermal cells (e.g. sundews) -Defense or reduce water loss -May be glandular

Question 27

What are bulliform cells? (on epidermis of some grasses)

Answer 27

-Cause leaf to curl when it dries. -Enlarged epidermal cells shrink when dry to help prevent further water loss

Question 28

Palisade parenchyma are where most...

Answer 28

chloroplasts are

Question 29

Spongy mesophyll parenchyma are large intercellular spaces; where...

Answer 29

gas exchange occurs; porous type of parenchyma

Question 30

Characteristics of shade leafs…

Answer 30

low light intensity – broad and thin – shallow palisade parenchyma – thinner epidermis

Question 31

Characteristics of sun leafs…

Answer 31

– high light intensity – small and thick – more palisade parenchyma. – thicker epidermis.

Question 32

What is a leaf scar?

Answer 32

Where leaf once was.

Question 33

Cladophylls are NOT..

Answer 33

leafs (no auxiliary bud at bass)

Question 34

What is a cladophyll?

Answer 34

Photosynthetic stem extensions

Question 35

What is a spine?

Answer 35

modified leaf -Protection from herbivory

Question 36

What is a thorn?

Answer 36

modified branch -Protection from herbivory

Question 37

What is a prickle??

Answer 37

modified epidermal cell -Protection from herbivory

Question 38

What is a tendril?

Answer 38

modified stem or leaf for climbing