vascular plants lab 6

characteristics of phylum coniferophyta

• branching, woody plants and most genera have long shoots and short shoots

• The secondary wood (xylem) is made up of tracheids, rays and resin canals.

• The leaves are spirally arranged or opposite (rarely whorled), and needle-like or scale-like, (rarely broad)

• The reproductive organs are unisexual cones

• The female cones (megastrobili) usually consist of a main axis with bract scales, each subtending or fused with an ovuliferous scale bearing 2 ovules

Pinus taxonomy

Phylum: Coniferophyta

Class: Coniferopsida

Order: Coniferales

Family: Pinaceae

Genus: Pinus

2 kinds of pine leaves

1. photosynthetic needles 

2. non-photosynthetic scale leaves

short shoots

short lateral branches that have needles

long shoots

twigs and branches that have many short shoots

xerophytic traits of pine needles

• thick cuticle

• sunken stomata

• hypodermis

• super compact mesophyll tissue

resin canals

• found in pine needles and pine stems

• lined with cells that make terpenoids (pine sap)

• sap acts as  anti-herbivory and anti-fungal compounds

transfusion tissue

• a specialized tissue in conifer leaves that surrounds the
  vascular bundles

• facilitates the radial transport of water and sugars between the
  xylem and phloem.

1. identify the genus

2. identify the part of the plant

3. identify a

1. pinus

2. leaf

3. resin canal

1. identify the genus'

2. identify the part of the plant

3. identify a-f

1. pinus

2. leaf

3. a. sunken stomata

b. epidermis

c. hypodermis

d. mesophyll

e. endodermis

f. transfusion tissue

growth rings

• Well-marked concentric zones of secondary xylem

• Their width indicates the favorability of the climate during each growing
  season

• In unusually cold or dry years, the rings may be narrow or even
  absent, whereas they will be wide in those years which have favourable
  weather.

false rings

• the production of two growth rings in one year

•  because a growing season is interrupted by a period of stress e.g.
  frost, insect attack, drought, fire or sapsucker damage then growth resumes
  after the stress has ended.

1. identify the genus

2. identify the part of the plant

3. identify a-d

1. pinus

2. stem

3. a. vascular cambium

b. phloem

c. resin canal

d. xylem

characteristics of pinus stems

• composed mostly of elongate tracheids

• narrow medullary rays (of parenchyma cells) extend radially through the xylem

vascular cambium function

The cambium adds many new cells that mature into secondary
xylem internally and into secondary phloem externally

cork cambium

• aka phellogen

• is a lateral meristematic tissue responsible for the production of the outer bark, which is a thick protective layer.

• forms during secondary growth, replacing the epidermis

• producing the periderm on the outside and phelloderm on the inside

periderm

• a layer composed of cork cells (phellem) which are dead cells that provide
  waterproofing and protection against pathogens and water loss

phelloderm

an extra layer of living cells that are still part of the periderm

medullary rays

• radial sheets of parenchyma cells that are in both stems and roots

• These rays run vertically and perpendicular to the growth rings, connecting the center to the outer bark

• Their main functions are to conduct water and minerals radially (lateral transport) and to store carbohydrates
  

characteristics of pinus roots

• protostelic taproot

• vascular core surrounded by a narrow pericycle, a prominent endodermis and cortex, and an epidermis with root hairs

• root hair zone limited

• undergo secondary growth and become woody

1. identify the genus

2. identify the part of the plant

3. identify a-f

1. pinus

2. root

3. a. periderm

b. cortex

c. phloem

d. xylem

e. resin canal

f. medullary rays

3 cell types in a pollen grain

1. generative cell

2. tube cell

3. prothallial cells

generative cells

produce sperm cells by mitosis

tube cells

grows through the megasporangial wall to make a pathway for the sperm cells to get to the egg

prothallial cells

don’t do anything (they’re vestigial leftovers from
evolution when the microgametophyte was free living)

1. identify genus

2. identify part of plant

3. what are the lines pointing at

1. pinus

2. pollen cone

3. microsporangia

identify a-c

a. pollen tube

b. pollen grain

c. tube cell nucleus

identify a-q

a. microsporangium

b. microsporophyll

c. meiosis

d. microspores

e. mitosis

f. haploid male gametophyte (pollen)

g. pollination then fertilization

h. diploid zygote

i. diploid sporophyte

j. pine embryo

k. archegonium with egg

l. haploid female gametophyte

m. mitosis

n. megaspores (only 1 lives)

o. meiosis

p. megasporophyll

q. megasporangium

1. identify the genus

2. identify the part of the plant

1. pinus

2. female cone (megastrobilus)

identify a-d

a. ovuliferous scale

b. bract

c. ovule

d. megasporangia

identify the structure

megaspore mother cell

identify stage of female gametophyte development

free nuclear stage

identify life stage and a-b

• mature female gametophyte

• a. integuments      b. arcgegonia

what is the line pointing at

egg cell

suspensor cells

fed embryo nutrients and plant hormones

what is the line pointing at

embryo

juniper taxonomy

Phylum: Coniferophyta

Class: Coniferopsida

Order: Coniferales

Family: Cupressaceae

Genus: Juniperus

white cedar taxonomy

Phylum: Coniferophyta

Class: Coniferopsida

Order: Coniferales

Family: Cupressaceae

Genus: Thuja

Characteristics of Juniper

• fragrant reddish tinted wood

• dioecious (few monoecious)

• megastrobili are fleshy and resemble berries (used to make Gin)

White cedar characteristics

• fragrant fine-grained wood

• rot resistant

yew taxonomy

Phylum: Coniferophyta

Class: Taxoposida

Order: Taxales

Family: Taxaceae

Genus: Taxus

yew characteristics

• dioecious

• ovules occur singly at the apices of short branches, enclosed in a fleshy aril

• megastrobili resemble red berries with opening to display poisonous seed

Ephedra taxonomy

Phylum: Gnetophyta

Order: Ephedrales

Genus: Ephedra

identify the structure

ephedra microsporangia

identify the structure

ephedra megasporangium

three orders in Gnetophyta

• ephedrales

• gnetales

• welwichiales

identify the species

ephedra