Exam Questions Flashcards
Give examples of control variables
age
gender
time intervals
What is the function of ribosome?
It produces enzymes
Give ways in which plant cells are different from bacterial cells
Plant cells have mitochondria
Plant cells have a nucleus, vacuole/chlorophyll
Why do bacterial cells not contain mitochondria?
They are too small
How can you compare how common an organism is in two sample areas?
- In area A, mark out a grid with a tape-measure
- Use a computer to randomly generate coordinates (to avoid bias results)
- Place a quadrate at the first coordinate and measure the variable
- Repeat in 10 or more coordinates and take a mean (improve reliability)
- Repeat procedure in area B
- Draw a bar graph to compare
How can you find how organisms are distributed across an area?
- Mark out a transect by putting a tape measure across the area of study
- At regular intervals (e.g. 2 meters apart) place a quadrate
- measure the variable (e.g. abundance, big tall)
- Repeat at 10 paces along transect, then move the transect and repeat again somewhere else
- Calculate a mean for each distance and plot on a line graph
What happens to the genetic material before the cell divides?
It duplicates
A gardener wants to produce a new variety of onion. Explain why sexual reproduction could not produce a new variety of onion
Fertilisation occurs, so leading to mixing of the genetic information
one copy of the gene from each parent
What is the equation of photosynthesis?
CO2 and water ——> glucose and oxygen
The leaf disc did not produce any oxygen in the dark, why?
light is needed for photosynthesis
Why did the leaf disc take in oxygen in the dark?
The plant needs oxygen fro aerobic respiration
What is an allele?
Alternative forms of the same gene
What is a recessive gene?
Only expressed if 2 copies are inherited
The lamp gives out heat as well as light. What could the student do tom make sure that heat from the lamp did not affect the rate of photosynthesis?
use an LED light
Give a factor which could limit the rate of photosynthesis
CO2
Describe the structure of a leaf and the function of the tissues in the leaf
waxy cuticle = reduces water loss
epidermis = no chloroplasts so allows light to penetrate
stomata = allows CO2in and O2 out
palisade = many chloroplasts to trap light, near the top of the leaf to receive more light
spongy = air spaces for rapid movement of gas
describe the effect of trypsin would have on baby food
break down and make it softer
In which part if the cell is energy released during respiration?
Mitochondria
Why is it possible to see bacterial colony but not a single bacterium?
One bacterium is very tiny. Many bacteria massed together in a colony can be seen
Why do muscle cells need a lot of mitochondria?
Mitochondria release energy which muscle need for movement
What determined the net movement of particles across a cell membrane?
The contraction of either side of the membrane
What does glandular tissue produce?
Enzymes or hormones
Where is soluble food absorbed?
In the small intestines
Where do most chemical reactions take place in a cell?
Cytoplasm
