topic 5 Flashcards
what are most of the sugars used by plants synthesised into
respiratory substartes
what is the biomass of a plant
the biologicl molecules
what is biomass
the chemical energy store in a plant
how is biomass measured
mass of carbon in an organism
what is dry mass
mass of the organism when the water contents is removed
how do you measure dry mass
the sample of the organism is dryed in an oven
mass of the organism is weighed at regular intervals
once the mass is content then the water contents is removed
how do you estimate the chemical energy stored in biomass
by burning the biomass in a colorimeter
describe the process of calorimetry
sample of dry biomass is burnt
the enrgy released is used to heat the volume of water
change in temperature is used to calculate the chemical energy
what is the gross pimary production
the chemical energy store in plant biomass in a given area or volume
what is the net primarry production
the chemical energy store in plant biomass after respiratory losses to the environment have been taken account
what is thee equation for NPP
NPP= GPP - R
how do consumers get their energy
by injesting plants and animals
how is energy lost
faeces
the food isnt eaten
urine
some is lost to the environment
what is the equation for the net productioon of consumers (N)
N= I - (F+R)
I= chemical energy store in ingetedd food
F-= chemical energy lost to the environment
R= respiratory lossees to the environment.
what do food chains and webs show
the transfer of energy hrough an ecosystm
what is thee role of decomposers in a food web
they break down undigested material
what are the two differnt ways that the transfer of energy can be increased
- energy lost to other organisms e.g pests is reduced
- the energy lost through respiration is reduced
what happens when we use insectides on pests
kills insects and pests that eat crops. so less biomass is lost from crops so NPP is greater
what is the role of using herbicides in order to increase the transfer of enrgy
killing weeds removes direct competition with the crop for energy from the sun
how do farmers incrrease the net production of their livestock
by controlling their conditions
so more energy is used for growth and less is used for respiration
e.g. placing them in pens so movement is restricted
- keeping them indoors to less energy is wastedd by heat loss
what are saprobiants
type of decomposer which breaks down dead plants and animals
what is the role of saprobionts
they secrete enzymes and digest their food externally
