Biology 102 "Practical Botany" - slide deck 6

Osmorphors

type of oil gland that produces scent compounds

Largest flower in the world

Rafflesia

A

Pistil (1 or >1 carpels)

B/C

Ovary/fruit

D

Petal (corolla)

E/F

Ovule/seed

G

Sepal (calyx)

H

Stamen

Flower

a branch in angiosperms modified to perform reproductive functions, with the fundamental architecture of 4 whorls: sepals, petals, androecium (stamens), and gynoecium (pistil)

There is a huge variation in flowers as a result of adaptation to a wide variety of pollination agents

Grass flower

reduced morphology for wind pollination

Oak flowers

unisexual flowers for outcrossing

A

Female inflorescence

B

Bracts

C

Stigma

D

Perianth

E

Female flowers

F

Anthers

G

Perianth

H

Male Flowers

I

Male inflorescence

Inflorescence

a cluster of several or many flowers

A sunflower is actually

an inflorescence

A

Disk flower

B

Ray Flower

C

Stigma

D

Fused Anthers

E

Corolla

F

Pappus Scale (modified sepal)

(Compound) umbel- type of inflorescence

Head - type of inflorescence

Catkin - type of inflorescence

A

Pollen tube

B

Ovule

A

Egg cell

B

Polar nuclei

C

Sperm cells

D

Endosperm (3N)

E

Zygote (2n)

Double fertilization

Occurs only in angiosperms (flowering plants)

First fertilization even (sperm + egg) = zygote or embryo (2N)

The other fertilization even (sperm + 2 polar nuclei) = endosperm (3N)

Fruit

develops from an ovary and sometimes the surrounding tissue after fertilization. Contains seeds, placenta, and ovary wall.

A/B

Ovule/seed

B

Placental tissue

D

Outer wall of pericarp/ovary wall

E

5

Apple

accessory fruit - a unique type of fruit

A

Hypanthium

B

Exocarp

Inferior ovary

an ovary completely or partially attached to the calyx (fused sepal); the other floral parts appear to arise from the top of the ovary

Superior ovary

an ovary that is free and separate from the calyx

King Rhododendron

Rhododendron rex - being tested in our arboretum