lesson 1 Bio

Plant Reproduction Study Guide

Ensure that you complete all activities and worksheets when instructed to do so.
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Work through the presentation by clicking on the background to navigate or activate animations.
The mouse icon will indicate clickable areas for animations or quizzes.
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A test at the end of the module provides a results page to print and hand in to your teacher.
Audio explanations are available, indicated by the speaker symbol.

Sections Covered:
- Flower structure
- Seed dispersal
- Pollination
- Germination
- Fruit development
- Test

Various quiz questions assess knowledge of flower structures, such as:
- What is the name of the structure labelled X? (options like sepal, stamen, etc.)
- Where is pollen made? (options: stigma, sepal, anther, ovary)
- Where is the ovule found in a flower? (options: petals, style, etc.)

Definition: Pollination is the transfer of pollen from the anther to the stigma.
**Types of Pollination:
- Cross-pollination:** Pollen travels from one flower to another, promoting variation.
- Self-pollination: Pollen falls from the anther onto the stigma of the same flower, which is undesirable as it reduces variation.
Methods of Pollination:
- By animals
- By wind

Insect-Pollinated Flowers:
- Sticky stigma
- Brightly colored petals
- Presence of nectar and scent
- Pollen with barbs for insects’ fur
- Anthers positioned to rub onto insects
Wind-Pollinated Flowers:
- Small and green petals
- Feathery stigma
- Exposed anthers
- Light and small pollen grains (produced in large numbers)
- No scent or nectar

Post-Pollination Process: A pollen tube grows down through the style to the ovule.
Fertilization: Male gamete fuses with the ovule.

After fertilization, petals, stamen, and sepals fall off.
The ovule becomes a seed, with:
- Testa: tough seed coat
- Micropyle: hole made by pollen tube
- Embryo Plant: developing plant within seed

Purpose: Disperses seeds to reduce competition for resources such as space, light, nutrients, and water.
- Methods of Dispersal:
- Wind
- Water
- Mechanical
- Animals

Identify the mechanism of the shown seeds (options like mechanical, wind, etc.).

Process: Water enters through the micropyle, activating enzymes and softening the testa.
Breakdown of starch in cotyledons to maltose and glucose occurs via amylase. Glucose is essential for respiration to provide energy for growth.
Components of Seed:
- Plumule: embryo shoot
- Radicle: embryo root
- Micropyle: entry point for water
- Testa: seed coat
- Cotyledon: starch stores

Seed loses mass initially due to usage of starch stores as it cannot photosynthesize yet, before increasing in weight as it develops.

Key findings from experiments include:
- Moisture: Essential for activating metabolic functions.
- Temperature: Warmth promotes enzyme activity.
- Oxygen: Required for respiration.
- Light: Not critical for initial germination, but necessary for the subsequent photosynthetic phase.

Various experimental setups observe effects of temperature, moisture, and oxygen availability on germination success.

Endnotes for further exploration and completion of worksheets based on information provided in the presentation.

For further exploration in plant biology, refer to www.clickbiology.com for resources and interactive modules.