B4g: Decay Flashcards Preview

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Flashcards in B4g: Decay Deck (11):
1

Factors increasing rate of decay (4)

+microorganisms, more of them to decay other living thing more quickly

+temperature (until optimum temperature reached): microbes respire faster, will grow and reproduce faster

+oxygen: microbes can use aerobic respiration to grow and reproduce faster

+water (moist conditions): allows for material to be digested and absorbed more efficiently and increase growth and reproduction

2

Groups of organisms involved in decay (2) + examples

detrivitrores - e.g. earthworms, maggots, millipedes, woodlice

decomposers (mostly saprophytes) - e.g. bacteria, fungi

3

What does detritivores do and how

increases rate of decay by increasing SA of dead remains for decomposers to act on

4

What is a saprophyte

an organism that feeds on dead and decaying material by extracellular digestion

5

How do saprophytes feed(3)

saprophytes release enzymes onto dead animal/plant

enzymes digest dead material through extracelullar digestion

saprophytes absorb digested substances

6

How does canning reduce the rate of decay(2)

foods are heated to kill bacteria

foods sealed in a vacuum to prevent entry of oxygen and bacteria

7

How does cooling reduce the rate of decay

slow down bacterial and fungal growth and reproduction

8

How does freezing reduce the rate of decay

kill some bacteria and fungi and slow down their growth and reproduction(or stop it)

9

How does drying reduce the rate of decay

removes water so decomposers cannot carry out cell reactions, grow or reproduce

10

How does adding salt/sugar reduce the rate of decay(2)

decreases water concentration in the food, drawing out water from the decomposers through osmosis
-without water, they cannot carry out cell reactions, grow or reproduce

11

How does adding vinegar reduce the rate of decay

produce very acid conditions killing most decomposers