Year 11 Term 1 continued Flashcards
Biomass
Amount of biological matter measure as dry mass in kg
Carnivore
An organism that eats meat
Herbivore
An organism which eats producers (green plants)
Predator
An organism which hunts for food (a carnivore)
Producer
A green plant
Prey
An organism which is hunted by predators. can be carnivore or herbivore
What is a trophic level
This is a feeding level in the food chain. can be represented using numbers, starting at level 1
Further trophic levels are numbered subsequently according to how far the organism is along the food chain
Level 1 on the trophic level
Plants and algae make their own food and are called producers
Level 2 on the trophic level
Herbivores eat plants/ algae and are called primary consumers
Level 3 on the trophic level
Carnivores that eat herbivores are called secondary consumers
Level 4 on the trophic level
Carnivores that eat other carnivores are called tertiary consumers
What’s an apex predator
Carnivores with no predators
What’s a a decomposer
Break down dead plant and animal matter by secreting enzymes into the environment. Small soluble food molecules then diffuse into the microorganism
What happens to the amount of biomass and energy contained in living things as you progress up the food chain
It decreases as only 10% of the biomass from each trophic level gets transferred to level above it
Energy lost in waste
Meat is easier to digest than vegetarian so carnivores produce less waste but there are still undigestible materials (hair, teeth etc.) which become faeces. Protein is broken down to urea and passed as urine
Energy lost due to movement
Some biomass is used for respiration i.e. movement
Movement uses lots of energy, muscles become hot, the more the animal moves the more energy is tranferred
Why do mammals need to eat more food than other types of animals
Because lots of heat energy lost through respiration and so these large animals need to eat lots of food to maintain a body temp which is higher than its surroundings and get the same increase in biomass
Pyramids of biomass
The amount of biomass at each stage of the food chain is less than at previous stage.
We can draw total amount of biomass at each stage to scale in a pyramid
Interpreting pyramids of biomas
At each stage the amount of energy passed on gets less
A large amount of energy in the biomass of plants supports as smaller amount and so on this is why the numbers of each organism at each level gets smaller too
How to calculate the efficiency of a biomass transfer
efficiency= biomass transferred to next level/ biomass available at previous level x 100
What is cyclic fluctuation
The number of predators and prey affect each other and tend to go up and down in a regular pattern e.g rabbits and foxes
Describe how cyclic fluctuation works
Because of extra food, the no. of rabbits increase
As more food, no. of foxes also increases
More foxes= more rabbits eaten so no. of rabbits decreases
Now foxes have less food so decreases
this goes on and on
What is food security
Having enough food to feed a population. Sustainable methods must be found to feed all people on earth
Biological factors which are threatening food security
Increasing birth rate Changing diets in developed countries means scarce food resources are transported around world new pathogens affecting farming environmental changes cost of agricultural inputs
How can the efficiency of food production be improved
By restricting energy transfer from food animals to the environment e.g. limiting their movement and controlling the temperature of their surroundings
How can the efficiency be improved in farming
Reducing no. of stages in food chain
Give concentrated (high protein) food for rapid growth
Shelter animals so protected from predators
Ad’s of intensive farming
Lots of chickens in small place
little or no food waste
heat energy waste kept to minimum
maximum no. of eggs and cheaper eggs/ meat
Disad’s of intensive farming
Chickens not able to act naturally
large barns need heating and lighting
legs may break as cannot carry weight of rapidly growing body
risk of disease as very cramped
Ad’s of free range farming
Cattle act naturally, calves stay with mothers for 6 months
feeding on grass or grain grown by farmer means no contamination
Disad’s of free range farming
Animals may take slightly longer to gain weight as more active
more land needed to provide grazing etc.
How to conserve fish stocks at a sustainable level
Control of net size and the introduction of fishing quotas
Function of oxygen in fermentation
Provides O2 for respiration, it’s filtered to remove unwanted microbes or dust ans enters at the base, so it bubbles through the liquid in the fermenter
Function of paddle stirrer in fermentation
Keeps microbes in suspension and maintains an even temperature ensuring O2 and food are evenly spread
Function of warm water outlet in fermentation
Allows heat released from the respiring microbes to leave the water-cooled jacket
Function of the food inlet in fermentation
Allows nutrients to enter at controlled rate ensuring microbes kept at correct stage in their growth
Function of steam inlet in fermentation
Steam blown through contents to raise temp to optimum
Function of pH/temperature probe in fermentation
CO2 would alter pH and affect activity of microbial enzymes. Probe ensures levels stay constant
Function of outlet- harvest line in fermentation
Enables the product to be harvested
What is mycoprotein
Made by a fungus called fusarium and is a protein rich food suitable for vegetarians. Is manufactured in a fermenter
How is mycoprotein made
Grown in aerobic conditions, the fungus requires glucose for respiration and minerals
Temp controlled using cooling jacket if above 35*C could slow growth
Waste gases leave fermenter at top
Mycoprotein is heated to break down poisonous substances
Then dried in huge centrifuge before flavourings added
