biomes
Biosphere: all parts of the earth where organisms live
Biome: divisions of a biosphere
-Desert, grassland, shrubland, temperate deciduous forest, tropical forest, tundra
Temperature: Latitudinal variation in the intensity of sunlight
-Sun’s rays arrive almost perpendicular near the equator; more heat is delivered
-Sun’s rays are spread out near the poles; less heat is delivered there
Precipitation:
High temperature= hot air rise
Hot air cools as it moves upward
Cold air holds less water vapor= Rain
Climograph: a graphical representation of mean annual temperature and precipitation (these are based on averages).
Temperature and precipitation are a correlation, not a causation. Precipitation and temperature are not the only factors which affect the distribution of a species
Biome: divisions of a biosphere
-Desert, grassland, shrubland, temperate deciduous forest, tropical forest, tundra
Temperature: Latitudinal variation in the intensity of sunlight
-Sun’s rays arrive almost perpendicular near the equator; more heat is delivered
-Sun’s rays are spread out near the poles; less heat is delivered there
Precipitation:
High temperature= hot air rise
Hot air cools as it moves upward
Cold air holds less water vapor= Rain
Climograph: a graphical representation of mean annual temperature and precipitation (these are based on averages).
Temperature and precipitation are a correlation, not a causation. Precipitation and temperature are not the only factors which affect the distribution of a species
4.2 Energy Flow
Food Chains: show the flow of energy through the trophic levels of a feeding relationship.
Trophic level: feeding position of an organism in a food chain. Food Web: diagram that shows how food webs are linked together in a complex relationship. -The food web has a number of advantages over a food chains including: More than one producer supporting a community A single producer being a food source for a number of primary consumers A consumer may have a number of different food sources on the same or different trophic levels A consumer can be an omnivore, feeding as a primary consumer and as a consumer at higher trophic level Decomposition: process by which organic matter is broken down into simpler forms. -Allows for the formation of soil, the recycling of nutrients stored in the organic materials Saprotrophs: secrete digestive enzymes into dead organism, which hydrolyze biological molecules of which the dead organism is composed -Saprotrophs are essential in the flow of nutrients through ecosystem, which would otherwise accumulate in debris |
Most ecosystems rely on a supply of energy from sunlight. Autotrophs (producers) such as plants, eukaryotic algae and cyanobacteria, can harvest their energy through photosynthesis. Heterotrophs also use the energy in sunlight indirectly, when consuming other producers and obtaining their energy. The amount of energy supplied by sunlight, depends on the location of the organism.
Light energy is covered to chemical energy in carbon compound by photosynthesis. Producers absorb the sunlight by using chlorophyll and other pigments. This is then produced into chemical energy, which is then released though cell respiration as a waste heat (most of this energy is maintained inside the cells and tissues of the producer).
Chemical energy in carbon compounds flows through food chains by means of feeding. A food chain is a sequence of organisms on which each feeds on the previous one. Consumers gain energy from the carbon compounds in the organisms that they ingest.
-Primary consumers feed on producers
-Secondary consumers feed on primary consumers
-Tertiary consumers feed on secondary consumers
-Primary consumers feed on producers
-Secondary consumers feed on primary consumers
-Tertiary consumers feed on secondary consumers
Energy released by respiration is used in living organisms and converted to heat. Through cell respiration, all cells have the ability to produce ATP, by the process of oxidation of compounds such as carbohydrates and lipids. Despite the use of cell respiration, not all the energy provided by the oxidation of carbon compounds is transformed into ATP . Living organisms need energy for cell activities such as:
-Syntesis of large molecules such as DNA, RNA, and proteins.
-Pumping molecules or ions across membranes by active transport
-Moving things around inside the cell, such as chromosomes or vesicles, or in muscle cells the protein fibers that cause muscle contractions.
-Syntesis of large molecules such as DNA, RNA, and proteins.
-Pumping molecules or ions across membranes by active transport
-Moving things around inside the cell, such as chromosomes or vesicles, or in muscle cells the protein fibers that cause muscle contractions.
Living organisms cannot convert heat to other forms of energy. Some energy conventions that living organisms can perform are:
-Light energy to chemical energy in photosynthesis.
-Chemical energy to kinetic energy in muscle contraction.
-Chemical energy to electrical energy in nerve cells.
-Chemical energy to heat energy in heat-generating adipose tissue.
-Light energy to chemical energy in photosynthesis.
-Chemical energy to kinetic energy in muscle contraction.
-Chemical energy to electrical energy in nerve cells.
-Chemical energy to heat energy in heat-generating adipose tissue.
Heat lost from ecosystems: according to the laws of thermodynamics in physics, heat passes from hotter to cooler bodies, so heat produced in living organisms is all eventually lost to the abiotic environment. Energy losses between trophic levels, restrict the length of food chains and the biomass of higher trophic levels. The biomass makes up the cells and tissues of organisms, including the carbohydrates and other carbon compounds. Ecologists can measure how much energy is added per year by groups of organisms to their biomass. these are calculated per square meter of ecosystem so that different trophic levels are compared. For secondary consumers, the amount of energy is always less per year per square meter of ecosystem than in primary consumers. Reasons for loss of energy is ecosystems are:
-Organisms in a trophic level are not usually entirely consumed by organisms in the next trophic level.
-Not all parts of food ingested by the organisms in a trophic level are digested and absorbed.
-Most of the energy in food that is digested and absorbed by organisms in a trophic level is released by them in respiration for use in cell activities.
-Organisms in a trophic level are not usually entirely consumed by organisms in the next trophic level.
-Not all parts of food ingested by the organisms in a trophic level are digested and absorbed.
-Most of the energy in food that is digested and absorbed by organisms in a trophic level is released by them in respiration for use in cell activities.
I=input, A=assimilation, R=respiration, NU=not utilized, P=production, B=biomass
-Biomass total dry mass of organic matter in organisms of ecosystems
Organic matter = carbon compounds such as carbohydrates, lipids and proteins
Most matter usually includes water (not organic) so the matter has to be dried
-Biomass total dry mass of organic matter in organisms of ecosystems
Organic matter = carbon compounds such as carbohydrates, lipids and proteins
Most matter usually includes water (not organic) so the matter has to be dried
-Gersmehel Nutrient Cycle:
Model of nutrient storage and flow for terrestrial ecosystems
Three storage compartments: biomass, litter, soil
Arrows represent nutrient flows
Thickness of arrow represent rates of nutrient flow
Model of nutrient storage and flow for terrestrial ecosystems
Three storage compartments: biomass, litter, soil
Arrows represent nutrient flows
Thickness of arrow represent rates of nutrient flow
Biomagnification:
Process in which chemical substances become more concentrated at each trophic level
As each individual eats contaminated food, it builds up these chemical substances
When large number of contaminated individuals are eaten, they pass on a high concentration of chemicals to the predator
Process in which chemical substances become more concentrated at each trophic level
As each individual eats contaminated food, it builds up these chemical substances
When large number of contaminated individuals are eaten, they pass on a high concentration of chemicals to the predator
C.2 Communities and ecosystems
Most species occupy different trophic levels in multiple food chains. The trophic level of an organism is its feeding position on the food chain. Feeding relationships are mostly like a we, meaning that they can vary depending on the situation, when describing the trophic level of an organism, there has to be reference to a specific food chain.
A food web show all the possible food chains in a community. Consumers usually feed on more than one species, but they are also fed by more than one species, making the food web and trophic levels complex for understanding.
The type of stable ecosystem that will emerge in an area is predictable based on climate. Climate s a property that is developed by the interactions of a number of variables which include temperature and precipitation.
-Temperature influences rates of cell respiration, photosynthesis, decomposition, and transpiration and ultimately impacts productivity.
-Photosynthesis also impacts productivity by influencing rates of photosynthesis and rates of decomposition.
-Temperature influences rates of cell respiration, photosynthesis, decomposition, and transpiration and ultimately impacts productivity.
-Photosynthesis also impacts productivity by influencing rates of photosynthesis and rates of decomposition.
The percentage of ingested energy converted to biomass is dependent on the respiration rate. Production in plants occur once organic matter is synthesized through photosynthesis. In animals, production occurs when food is absorbed after digestion. Gross production is the total number of organic matter produced per unit area per unit time by a trophic level in an ecosystem. Net production is the amount of is the amount of gross production remaining after subtraction of the amount used by respiration in the trophic level.
Gross and net production values are calculated through this equation:
net production= gross production- respiration
Gross and net production values are calculated through this equation:
net production= gross production- respiration
Disturbance influences the structure and rate of change within ecosystems. Secondary succession occurs in an area where there is already, or has been an ecosystem. Close to the time of disturbance, rates of system respiration and productivity increase rapidly as there is an accumulation of biomass.
In closed ecosystems, energy but not matter is exchanged with the surroundings. In open systems, both matter and energy are exchanged with the surroundings. Three different models can be created.
-Isolated systems: exchange neither matter nor energy.
-Natural systems: exchange both matter and energy
-Ecological systems: exist along continuum.
Data- based questions
photosynthesis 2.9
Photosynthesis is the production of carbon compounds in cell using light energy. The carbon compounds produced are lipids, proteins and carbohydrates. Living organisms require the carbon compounds in order to build the structure of their cells and carry out processes of life.
-Conversion of light energy into chemical energy
-Chlorophyll is the main photosynthetic pigment
-Conversion of light energy into chemical energy
-Chlorophyll is the main photosynthetic pigment
Wavelengths of light: visible light has a rage of wavelengths with violet being the shortest and red the longest. Sunlight is made up of all the wavelengths of electromagnetic radiation that our eyes can detect. Wave lengths that are detected by the eye, are those used in photosynthesis.
-The shortest wave lengths such as x-rays and ultra violets have high energy, while longer wavelengths such as infrared and radio waves have low energy.
Wavelengths- Photosynthesis
-Chlorophyll A and B absorb both red (650 -750 nm) and blue (450 - 500 nm) wavelengths
-Green (500 -550 nm) light is transmitted or reflected by chlorophyll.
-The shortest wave lengths such as x-rays and ultra violets have high energy, while longer wavelengths such as infrared and radio waves have low energy.
Wavelengths- Photosynthesis
-Chlorophyll A and B absorb both red (650 -750 nm) and blue (450 - 500 nm) wavelengths
-Green (500 -550 nm) light is transmitted or reflected by chlorophyll.
Light Absorption by Chlorophyll: it absorbs red and blue light most effectively, and reflects mostly green light
-The absorption of sunlight is caused by pigments, which are substances that appeared colored to us since they absorb the waves (non-colored objects don't absorb light). All plants use different photosynthetic pigment, but the most common is chlorophyll.
-The absorption of sunlight is caused by pigments, which are substances that appeared colored to us since they absorb the waves (non-colored objects don't absorb light). All plants use different photosynthetic pigment, but the most common is chlorophyll.
-Absorption spectrum: shows the quantity of each wavelength of light absorbed by a specific pigment
-Action spectrum: the summation the individual absorption spectra of the various pigments
The graph above illustrates:
-Y axis as the rate of photosynthesis
-The maximum absorption rate are at the blue end and red end of the visible spectrum, therefore it emits green light.
-Action spectrum: the summation the individual absorption spectra of the various pigments
The graph above illustrates:
-Y axis as the rate of photosynthesis
-The maximum absorption rate are at the blue end and red end of the visible spectrum, therefore it emits green light.
Photosynthesis:
Light dependent reaction:
-Energy absorbed by chlorophyll/protein complex and is used to produce ATP
-Oxygen is produced in photosynthesis from photolysis of water. This process only occurs in the light (photo) and lysis means disintegration. Photolysis of water: Energy absorbed by chlorophyll is used to split water molecules, forming oxygen and hydrogen
Light independent reaction:
-Carbon dioxide absorbed for use in photosynthesis
-Inorganic carbon dioxide molecules transform organic carbon dioxide molecules via fixation.
-Use hydrogen (from photolysis) and ATP.
Light dependent reaction:
-Energy absorbed by chlorophyll/protein complex and is used to produce ATP
-Oxygen is produced in photosynthesis from photolysis of water. This process only occurs in the light (photo) and lysis means disintegration. Photolysis of water: Energy absorbed by chlorophyll is used to split water molecules, forming oxygen and hydrogen
Light independent reaction:
-Carbon dioxide absorbed for use in photosynthesis
-Inorganic carbon dioxide molecules transform organic carbon dioxide molecules via fixation.
-Use hydrogen (from photolysis) and ATP.
Effects of Photosynthesis on the Earth: changes on the earths atmosphere, ocean and rock deposition due to photosynthesis. Rise in oxygen concentration for 2%, this is known as the Great Oxidation Event. First glaciation due to green house effect, probably due to photosynthesis.
Energy is needed to produce carbohydrates and other carbon compounds from carbon dioxide. Plants use photosynthesis to convert carbon dioxide and water into oxygen and water. The chemical process that involves putting energy is known as endothermic.
Energy is needed to produce carbohydrates and other carbon compounds from carbon dioxide. Plants use photosynthesis to convert carbon dioxide and water into oxygen and water. The chemical process that involves putting energy is known as endothermic.
Limiting Factors of Photosynthesis:
-Temperature:
Increased molecular collisions
Enzymes denature
-Light intensity:
Visible light (especially red and blue) is essential for activity of chlorophyll during the light-dependent reactions
Positive correlation between light intensity and photosynthesis
Enzymes already working at max rate
-Carbon dioxide concentration:
CO2 is essential for Calving cycle for the production of carbohydrates
Positive correlation between CO2 concentration and photosynthetic rate
-Temperature:
Increased molecular collisions
Enzymes denature
-Light intensity:
Visible light (especially red and blue) is essential for activity of chlorophyll during the light-dependent reactions
Positive correlation between light intensity and photosynthesis
Enzymes already working at max rate
-Carbon dioxide concentration:
CO2 is essential for Calving cycle for the production of carbohydrates
Positive correlation between CO2 concentration and photosynthetic rate