Lab Mod. 4 (Plant Morphology and Cladistics)

Question 1

What makes eukaryotic organisms plants
(kingdom Plantae) [5 total clades]

Answer 1

use chlorophyll a and b
cell wall composed of cellulose (and more)
plastids bound by ONLY 2 plasma membranes capable of photosynthesis
store food as starch
alternation of generations (for true land plants)

Question 2

what is “alternation of generations”

Answer 2

has a haploid multicellular gametophyte
diploid multicellular sporophyte
(different stages in life)

Question 3

what are the basic adaptations for land

Answer 3

• ability to absorb water when it’s present and prevent water loss
• “skeletal” system to hold up leaves and stems (reach the sun)
• protective packaging for gametes and embryos, decreased reliance on the presence of water for reproduction

Question 4

what are the types of tissues?

Answer 4

all plants are made up of
ground tissue
vascular tissue
dermal tissue

Question 5

what is the function of ground tissue?

Answer 5

makes up majority of plant body
- parenchyma: most abundant and versatile, nondescript structure
- collenchyma: strong pliable supporting cells made of cellulose fibrils and pectin, form the veins of leaves
- sclerenchyma: contain lingin, strengthens and waterproofs the plant

Question 6

what function does vascular tissue serve?

Answer 6

transport water and food throughout the plant
- xylem: conduct water and dissolved mineral from roots to the rest of the plant. the cells (vessels and tracheids) are dead at maturity
- phloem: moves sugars from leaves to rest of plant. the main cells are alive at maturity

Question 7

what are dermal tissues for?

Answer 7

cover and protect the surface of the plant body
- epidermis: single layer of cells covering the outer body parts of plant. cells secrete a waxy coating called the cuticle

Question 8

what is the cutivle

Answer 8

waxy coating that protects against water loss and invasion by microorganisms

Question 9

what are trichomes

Answer 9

structures made of special dermal cells
can be unicellular or multicellular, many functions (stinging, befuddling insects, reflecting light)

Question 10

where does mitosis occur? (mitosis- parent cell => 2 identical daughter cells)

Answer 10

specific locations within the plant called meristems
- apical meristems: located at the very tip of shoots/roots
- lateral meristems: thicken the plant stem (ex: vascular cambium)

Question 11

vascular cambium

Answer 11

located between phloem and xylem in stem
- produces phloem to its outside
- produces xylem to its inside
creating tree rings

Question 12

green algae

Answer 12

share same chloroplast structure, photosynthetic pigments, enzymes, etc because of recent common ancestor

lack all terrestrial adaptations

can be unicellular, colonial, or multicellular

Question 13

bryophyte

Answer 13

dominant life stage = haploid gametophyte
covered in waxy coating to retain moisture
no true roots - rhizoids which anchor the moss
absorb water via diffusion through surface
no true vascular tissue

Question 14

examples of bryophytes

Answer 14

mosses, liverworts, hornworts

Question 15

bryophyte reprodcution

Answer 15

rely on water for sperm to find egg
sporophyte grows directly on top of gametophyte
produces single celled spores which explode from capsules

Question 16

ferns (pterophyte)

Answer 16

waxy coating to retain water - perforated with stomates to allow the exchange of gasses
true roots
true vascular system - can grow tall/support
NO true seeds or spores
dominant stage of life = diploid sporophyte

Question 17

fern reproduction

Answer 17

one type of multicellular gametophyte produces archegonia and antheridia
relies on water for fertilization
diploid fern sporophyte grows - briefly dependent on gametophyte

Question 18

gymnosperms

Answer 18

woody tissue
growth in vascular cambium produces rings and girth of stem
waxy covering
stomates
true roots

Question 19

how are tree rings produced?

Answer 19

vascular cambium produces neww xylem inside and new phloem outside - wood is the accumulationo of dead tissues
the secondary xylem accumulates, secondary phloem is eventually lost

Question 20

examples of gymnosperm

Answer 20

conifers
redwoods
sequoias

Question 21

gymnosperm reproduction

Answer 21

spores inside sporophytes where the gametophyte develops (no free living gametophyte)
not a true seed becasue it lacks the chambers (ovaries) that angiosperm seeds develop
“naked” seed that is multicellular package that contains diploid sporophyte and food supply
seeds develop on cones with little protection

Question 22

angiosperms

Answer 22

• flowering plants to attract and reward pollinators/dispersers
  waxy coating to prevent evaporation
  stomata
  true roots
  vascular system

Question 23

angiosperm reproduction

Answer 23

meiosis
mostly “perfect flower” male and female reproductive parts in same flower
male structure = stamen
female structure = pistil
the anther within the stamen produces pollen grains which are carried to the stigma in the pistil and then carried down through the rest of the pistil till it reaches the ovary and can force fertilization

Question 24

angiosperm seeds

Answer 24

after fertilization the pistil enlarges to become the seed
no pollen tube and new pollen prevented from reaching the egg
food supply = triploid endosperm (2 from mom)
endosperm helps disseminate seeds as birds eat the seeds for the endosperm