4. Nutrients and energy - 4.1. Nutrients Flashcards
What is a nutrient?
Any substance used by an organism for growth, repair or as a source of chemical energy
Give some examples of animal nutrients
Carbohydrates, proteins, lipids (fats), vitamins and minerals
Name a major nutrient for plants
Carbon dioxide
What to plants use carbon dioxide for?
To make sugars (during photosynthesis)
Why are proteins essential?
They are used in growth and repair and for the production of new cells.
They can also serve as an energy supply when body stores of lipids and carbohydrates are low
Why must animals consume proteins?
They cannot produce their own amino acids
What are amino acids?
The repeating units in protein
What are carbohydrates used for?
They are a source of energy
What are the 2 major groups of carbohydrates?
Sugars and starch
What are sugars?
Small molecules that taste sweet. They are used for quick energy release
What is starch?
A large molecule made up of many glucose molecules bonded together. It is digested into glucose which is absorbed into the blood and used as an energy source
What are lipids used for?
They are energy sources, insulation and a source of vitamins
Why are fats and oils called “energy dense”?
A given mass of fat or oil contains more energy than the same mass of carbohydrates
What are vitamins?
Molecules that are essential for the growth and activity of all organisms
Why are vitamins and minerals classed as micronutrients?
Because only small quantities are needed
Plants and animals need vitamins. How are their needs different?
Plants make their own vitamins, but animals must consume them in their diet
Plants and animals need minerals. How are their needs different?
Plants absorb minerals from air, water or soil, but animals must consume them in their diet
What is the function of carbon?
It’s essential to make all organic molecules
What is the function of nitrogen?
It helps make proteins - without it, organisms cannot grow
What is the function of magnesium?
It helps to make chlorophyll
What is the function of calcium?
It builds the shells of molluscs and the skeleton of coral
What is the function of iron?
It helps in the making of haemoglobin to transport and store oxygen
Summarise how elements are recycled in marine ecosystems
Nutrients are taken up by producers
Producers are eaten by herbivore animals
Herbivores are eaten by carnivores
Marine animal waste (faeces, shedding, dead animals) containing nutrients = marine snow falling to seabed
Decomposers manage the waste and make nutrients available again
