(a)(i) Name two types of germination of seeds giving one example of each type.
(ii) Describe a simple experiment to demonstrate that oxygen, water and warmth are necessary for germination of seeds.
(b) State two distinguishing features each of
(i) epiphytes
(ii) parasites
(c) Give two examples o parasitic plants.
Explanation
(a)(i) Types of germination with examples: Epigeal germination e.g. cowpea/bean seed. Hypogeal germination e.g maize grain/wheat/oil palm/guinea corn.
(ii) Experiment to demonstrate factors necessary for germination:
- Some dry cotton wool are placed at the bottom of each of conical flasks labeled A,B,C and D.
- In flask A, few/2 to 4 bean seeds are placed on dry cotton wool; the flask is placed in a warm place.
- In flask B the cotton wool is moistened together with the seeds in it
- Test tube containing pyrogailic acid and caustic soda/pyrogaliol is suspended in flask B; to absorb oxygen; flask B is put in a warm place
- In flask C a little water is placed on the cotton wool and seeds and it is placed in a warm place; In flask D a little water is poured on the seeds to moisten them and it is placed in the refrigerator
- the four flasks are observed for four to five days/few days; only the seeds in flask C germinated. This shows that oxygen, water/moisture and warmth are necessary for seed germination.
(b)(i) Epiphytes: -
- A plant which grows on/supported by another plant/lives on trees
- Where it competes with other producers for sunlight
- It does not take manufactured food from the support plant
- It is capable of photosynthesis.
(ii) Parasites: -
- An organism that lives on or in another organism is called a host
- it obtains shelter/protection/food from the host At the expense of the host/leading to harm/death of the host.
(c) Examples of plant parasites: -
Dodder
Striga
Mistletoe
Cassytha