GCSE Biology Question Analysis Topic: Biology - Short Questions
Exam Questions:
1) Write the equation that helps in deriving the net primary productivity of an ecosystem.
2) (a) Explain "birth rate" in a population by taking a suitable example.
(b) Write the other two characteristics which only a population shows but an individual cannot.
3) When and where do chorionic villi appear in humans? State their function.
Answers:
For GCSE Biology, you should know:
1) Net primary productivity (NPP) can be calculated as gross primary productivity (GPP) - respiratory losses (R).
2) (a) Birth rate is the production of a new individual by birth, hatching, etc. It can be expressed as the number of births per one thousand individuals of a population annually.
(b) 1. Population size / density; the number of a species' individuals per unit area or volume
2. Population dynamics; the growth of a population changes over time and depends on a variety of factors, including food availability, predation, pressure and weather. Other factors may include natality, mortality and immigration/emigration.
3) Chorionic villi appear on trophoblast after implantation. They are finger-like projections. It is covered by uterine tissue and maternal blood.
Function: The structural and functional units formed between the maternal body and the embryo when chorionic villi and uterine tissue are interdigitated with each other is called the placenta. Its function is to nourish the developing embryo.
Work hard for your GCSE Biology examination!
End of analysis. Great!
