LAB 6

FAMALY ASTERACEAE

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Composite flower head of a sun flower.

Cross section of the composite head; where are the disk floret, ray floret, bract, receptacle?

*check out the labeled photo in lab 3.

This is a disk floret, is it male or female? (do you see the anther AND stigma?) The hair at the top of the ovary is called pappus (they are the reduced sepals).

A ray floret; one of its purposes is to attract insects. This floret only has a pistil (no stamen), so it's imperfect.

What kind of symmetry does this floret display?

FAMILY POACEAE

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"Grass" family

The inflorescence at the top is composed of many spikelets.

Each of the circled structures is a floret, and the stem-like structure linking them together is called the rachilla. Glumes (removed) would surround these florets.

Dissecting open one of the florets reveals 2 stamens, one pistil and an ovary.

I suspect one stamen is missing because monocots parts are usually in 3's.

A closer look at the top of the ovary reveals the stigma and style. (Thank you to Queenie for the photo)

Parallel veins of a grass blade (it's a monocot)

LILY-LIKE MONOCOTS (FAMILY LILIACEAE AND FRIENDS)

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Note the lack of sepal, what happened to the structure?

6 stamens

This one also has 6 stamens

Tepals - the fusion of petals and sepals


Family Orchidaceae

An orchid flower

Can you name the floral parts from the above 2 pictures? tepal, column, labellum, pollinia

Labellum (purple, on the left) and column (white, on the right)
What makes up the labellum? and column?

A closer look at the pollinia

With bottom half of the flower cut away, he stigmatic surface is much more apparent.