Biology Flashcards
Learn year 8 biology
What is an enzyme?
A biological catalyst, something which speeds up chemical
reactions without being used up
Give 3 problems caused by being underweight.
Health problems like a poor immune system, lack of energy
or tiredness, lack of vitamins or minerals.
Accept any other reasons that seem fitting for the question.
Why does digestion make large molecules into
smaller ones?
They can then pass into the blood.
What is the energy in food measured in?
Joules (J)
Accept kilo joules (Kj)
What type of alcohol is in alcoholic drinks?
Ethanol
What does the body use lipids for?
Insulation (keeping warm)
Accept for energy
What does a deficiency of vitamin A lead to?
Night blindness (unable to see in dim light).
What would you use to test food for starch?
Iodine
What does the body use carbohydrates for?
Energy
How does carbon monoxide in tobacco smoke
affect people?
It stops the blood from carrying as much oxygen as it
could, by binding to red blood cells instead of oxygen.
Name the 7 components of a healthy diet.
Carbohydrates, Lipids, Proteins, Vitamins, Minerals, Water,
Fibre.
How do you test food for sugar?
Add benedict’s solution
Give 3 health conditions caused by smoking.
Lung cancer, heart attacks, strokes.
Accept any other reasons that seem fitting for the question.
What is the term for different
organisms trying to get the same
resource?
Competition.
What do we call the features which
allow organisms to survive the best?
Adaptations.
Give 4 adaptations of desert plants.
A waxy layer preventing water from escaping.
Stems that store water.
Widespread roots to collect water from a
large area.
Spines instead of leaves to reduce water loss
and prevent them from being eaten.
Accept any other reasons that seem fitting for the question.
Give an adaptation of deciduous trees.
They lose their leaves in winter.
What is the name for the range of
living organisms in an area?
Biodiversity.
Give an example of discontinuous
variation.
Blood group, eye colour
Accept any other reasons that seem fitting for the question.
Where is DNA found in cells?
The nucleus.
What do we call a section of a
chromosome which codes for a
specific characteristic?
A gene
. How many chromosomes are found in a halploid nucleus.
23 (46 in a normal nucleus)
Summarise natural selection in
peppered moths.
Before the industrial revolution, most
peppered moths were pale and hid on pale
trees. The odd black moth was seen and eaten
by birds.
Pale moths survived, so most moths continued to be pale.
During the industrial revolution, the trees
around cities got sooty and darker.
The pale moths stood out and were eaten by
birds.
The darker moths survived to reproduce, and
so the dark form became more common around
cities.
Accept any other reasons that seem fitting for the question.
Give 4 causes of extinction
Changes to the environment.
Habitat destruction.
Disease.
New predators or competitors.
Give the word equation for
photosynthesis.
Carbon dioxide + Water → Glucose + Oxygen
What do producers do?
Make their own food.
Why are animals called consumers?
They eat other organisms to survive.
Why is there a waxy
layer on a leaf?
This reduces water loss by evaporation.
What is the word equation for photosynthesis?
carbon dioxide + water -> gluclose + oxygen.
In what part of the cell does photosynthesis occur?
The chloroplasts
