Life Sciences Grade 12: Biodiversity of Plants and Reproduction

Flashcards on the biodiversity of plants, reproduction, and seeds, covering topics such as seed significance, structure, advantages, food sources, seed banks, and related terminology.

What makes seed-bearing plants (Spermatophyta) successful?

Seeds are adapted to be dispersed, store reserve food, and are protected by the testa. They also provide food for developing seedlings.

What is the function of the testa (seed coat)?

It protects the contents of the seed from drying out.

What are the components of the embryo within a seed?

Radicle, plumule, and axis.

What are the four advantages of seeds for plants?

The seed has a dispersal mechanism, the testa and cotyledons help the embryo survive unfavourable conditions, and provides protection in the early stages of development; the cotyledon is able to provide the seedling with energy for growth until it is able to produce its own food.

What are the three categories of plants with edible seeds?

Grains, legumes, and nuts.

What is the significance of grains as a food source?

An important source of energy-rich carbohydrates (starch), and the testa provides a large amount of fibre.

What is the significance of legumes as a food source?

Important source of proteins, low in fat, high in fibre, and easily cultivated, transported and stored.

What is the significance of nuts as a food source?

High protein content, high in fibre, antioxidants, and mono-unsaturated fatty acids.

What is a seed bank?

A facility used to store seeds of various plants and crops to maintain biodiversity.

What are two important seed banks?

Kew’s Millenium Seed Bank Project (UK) and International Seed Vault (Sweden).

Under what conditions must seed banks be kept?

Very cold (-20°C) and dry environment.

What factors influence biodiversity that seed banks aim to protect against?

Habitat destruction, climate change, and overuse of species.

What are the uses for seed banks in maintaining biodiversity?

Re-establish endangered or extinct plants, rehabilitate damaged plants, cultivate overexploited plants, cultivate new hybrids, conserve endemic species, and produce plant material for research.

What is spermatophyta?

The phylum made up of seed-bearing plants.

What does endemic mean?

Means that the species only occurs in that area or region and nowhere else in the world.

What is nuclear DNA?

Is the DNA found in the nucleus.

The radicle grows into the…

First root

The part of the seed that protect the embryo in its early stages are…

Testa and cotyledon

The seedling obtains its food…

From the cotyledon until it is able to produce its own food.

The phylum that produces seed-bearing plants is called…

Spermatophyta

The phylum that produces naked seeds is called…

Gymnosperm

The phylum that bears seeds within fruit is…

Angiosperm