IB ESS Topic 2.2

Productivity

Photosynthesis

cellular process where CO2 and water are used w/ sunlight to form glucose and oxygen

What type of reaction is photosynthesis

chemical reaction that turns sun’s light energy into consumable chemical energy for organisms

who can perform photosynthesis

only autotrophs

aerobic respiration

uses oxygen and glucose to create ATP, CO2 and water

what organisms use cellular respiration to turn glucose into ATP

heterotrophs and autotrophs

what is released as extra in cellular respiration

heat energy

what is ATP

cellular energy

what do photosynthesis and cellular respiration have in common?

both are chemical reactions that transfer energy between trophic levels

what are trophic levels

represent the transfer of energy through an ecosystem or food chain from one level to next

what is the basic order of trophic levels

sun to autotrophs to heterotrophs

autrophs

auto=automatic, troph=energy. make their own food/energy. producers in an ecosystem

what do autotrophs eat

food made of glucose molecules broken down to release energy. 1st trophic level

photoautotrophs

use sunlight to make energy (plants, algae, etc). contain highest level of energy of all organisms in an ecosystem

chemoautotrophs

use chemical to make energy (all are bacteria). live in guts of organisms or in deep sea waters around ocean vents with no light

heterotrophs

hetero=other, troph=energy. obtain energy from source other than themselves. eat other organisms (auto and heterotrophs). make up all trophic levels other than first level. consumers that do aerobic respiration

photoheterotrophs

use carbon-based organic molecules from other organisms to make food. small % of living organisms. normally only secondary consumers. live in oxygen rich environments w/ little carbon dioxide (rely on other organisms). Ex: carnivorous plants

chemoheterotrophs

majority of heterotrophs and consumers. obtains both its energy and carbon from organic compounds. must eat other organisms. Ex: animals, protists, decomposers, etc

sun as trophic level

provides energy for nearly all organisms on earth. energy flow of life starts w/ sun (solar energy) which is combo of light and radiation energy

producers as trophic level

1st trophic level. organisms that harness sun’s energy via photosynthesis

primary consumers as trophic level

2nd level. organisms that eat producers (herbivores and detritivores). detritivores eat decaying plant material. use aerobic respiration to break down food to release energy

secondary consumers as trophic level

third level. eat primary consumers. small carnivores and some omnivores. use aerobic respiration

tertiary consumers as trophic level

4th level. eat secondary consumers. large carnivores and scavengers. use aerobic respiration

quaternary consumers as trophic level

5th level. eat tertiary consumers. large carnivores or scavengers. ex: humans

decomposers as trophic level

final trophic level that can affect everything at same time. break down dead organisms into biomolecules that can be further broken down to release energy and nutrients into soil. use aerobic respiration. help in nutrient cycling. ex: fungus, mold, bacteria

energy pyramid

simple schematic that visually represents how much energy (biomass), population and productivity levels exist at each trophic level

10% rule

moving from one trophic level to next loses 90% of energy as heat and kinetic energy (respiration) and feces too. kinetic energy used for hunting, hiding, reproduction, etc. Each trophic level only has 10% roughly stored energy from the level before. Causes a decrease in population too. DONT USE 10% RULE IF ACTUAL PERCENT IS GIVEN

food chain

linear depiction of how producers are consumed and how consumers are consumed. small part of giant food web. arrows always go to organism receiving energy from eating

food web

collection of food chains showing different pathways in which energy flows from one organism to the next

what should you do when naming organisms

UNDERLINE SCIENTIFIC NAMES

gross productivity

gain in all biomass of an organism before losses

Net productivity

gross productivity - losses. the actual amount of biomass after respiration

where is gross productivity greatest

coral reefs (shallow water close to land)

where is gross productivity lowest

deserts and deep ocean (little water and high heat)

ecological efficiency equation

(energy used in growth / energy supplied) X 100

Primary productivity is highest where

in areas where conditions for growth are the highest. high levels of insolation, good water supply, warm temperature, high nutrients, constant grow seasons

what are the levels of the ocean and where grows best

photic (top 200 m) has most light and plants grow here (most life), disphotic has less light (twilight), and aphotic (no light). There is a conveyor belt for the oceans to move water around

how does agricultural land connect to productivity

highly maintained and modified ecosystems. goal is to increase npp and biomass of crops. add water and nutrients. nitrogen and phosphorus are most limiting to plant growth. npp in agricultural land is less than other ecosystems despite modifications

total primary productivity

it is gross primary productivity. amount of light energy converted to chemical energy by photosynthesis per unit time (J m^-2 yr^-1)

net primary productivity

GPP - R. R is respiration. energy storage available for whole community of consumers

standing crop

total live material at a trophic level

consumer GSP

food eaten - fecal losses

consumer NSP

change in mass over time. GSP - R

efficiency of assimilation

(gross productivity / food eaten) X 100

efficiency of biomass productivity

(net productivity / gross productivity) X 100

photosynthesis equation

cellular respiration equation

primary productivity

gain in biomass for producers

secondary productivity

gain in biomass by consumers using carbon compounds absorbed and assimilated from ingested food

biomass

total mass of a living organism/amount of living material. always dry weight

respiration

breaking down food often in the form of glucose to release energy which is used in living processes

chemosynthesis

a process where microorganisms use chemical energy from inorganic molecules instead of sunlight to create food

1st law of thermodynamics

principle of conservation of energy. as energy flows through ecosystems, it can be transformed from one form to another but cannot be created nor destroyed

2nd law of thermodynamics

as energy is transferred or transformed in a system, it’s degraded to a less useful form of energy such as heat energy. entropy (disorder) also increases

productivity

the conversion of energy into biomass over time. it’s the rate of growth or biomass increase in plants and animals. measured for plants as mass per unit area per unit time (g m^-2 yr^-1)

biocides

substances or microorganisms that destroy, deter or render harmless living things (ex: disinfectants, pesticides (can include DDT) and don’t break down quickly/at all)