Saturday, September 25, 2010

Lab 1 - Parts of a flower

Parts of a flower
---

This is a flower of the Fuchsia plant. It has its sepals and petals spread out radially. What do we call this kind of arrangement?
 
A cross section through the flower. Can you name the different floral parts? and what is the positioning of the ovary relative to the stamens, petals, and sepals?
Here's a labeled picture and this flower has an inferior ovary.
*there should be a total of 8 stamens, but only 5 are shown here because of the sectioning. *edit: the hypanthium has been extended to the base of the ovary.

The next flower is a snapdragon.

It can only be cut into 2 identical halves, so its symmetry is zygomorphic.
If you look at the base of the right half, you can see its 2 carpels.

Here's a pea pod (legume).

The open space between each pea is its locule; locule number = 1. 
Note that the attachment of the peas are at the margins, therefore this is called marginal placentation.

A cross section through a tomato. The seeds are attached to the placenta (the white structures at the center) and this time it is at the centre of the ovary. What is its placentation? The areas occupied by the seeds, placenta and juice are the locules.

The Begonia flower is a monecious plant, meaning it has stamen only (male) flowers AND pistil only (female) flowers. These are imperfect flowers; perfect flowers have both male and female structures. The above is a male (staminate flower), how do we know?

If we take a look at the backside...there is an absence of ovary.

 Here's a female (pistillate flower) and the presence of an ovary; quite a noticeable difference.

...and the top view of the pistillate flower


A water lily in full bloom. Try naming all the structures in this picture.

The structures from the outside in: sepals, tepals?, petals, stamenoids, stamens, and pistils


Magnoliids
The Magnolia flower that perfumed the lab room.


Check out the tepal and stamen scars and their spiral arrangement.

Kam Ho carefully freed one of the Magnolia seed and left it dangling.

Some black pepper (Piper nigrum) from the Piperaceae family.

1 comment:

  1. excellent description.i really like it. it really help me alot.

    ReplyDelete