central organelle using gene;c instruc;ons as a control center strands of an organism s gene;c material (DNA) during most of the life cycle

Transcription

1 Cell structure and func.on Cell Theory The cell is the smallest unit of life. All living things are made of cells. All cells come from pre- exis;ng cells. nucleus central organelle using gene;c instruc;ons as a control center chroma;n strands of an organism s gene;c material (DNA) during most of the life cycle chromosome the shape of an organism s gene;c material aber it is copied and before it is split to produce new cells mitochondrion (plural: mitochondria) organelle where cellular respira;on takes place, providing energy to the cell Interna;onal School of Tanganyika MYP Science 1

2 Golgi complex organelle which modifies molecules from the E.R. and transports them to other sites within the cell centriole organelle found in animal cells, which organizes chromosomes during cell reproduc;on ribosomes small organelle which builds proteins from amino acids smooth endoplasmic re;culum tube- like organelle involved in the produc;on of lipids, carbohydrates, enzymes, and hormones rough endoplasmic re;culum organelle shaped like flawened sacs, which manufactures membranes, an;bodies, and insulin Interna;onal School of Tanganyika MYP Science 2

3 vacuole fluid- filled organelle, which stores various materials within the cell Similari;es between plant and animal cells cell membrane, nucleus & nuclear membrane, mitochondria, rough and smooth ER Differences between plant and animal cells cell wall, chloroplasts, vacuole size, centrioles Interna;onal School of Tanganyika MYP Science 3

4 Biological Molecules water the universal solvent and a requirement for all life on Earth carbon dioxide product of cellular respira;on, but also a building block of glucose during photosynthesis glucose sugar molecule made of 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms; the basic source of energy for most cells through the process of cellular respira;on nucleic acids the building block of gene;c material such as DNA and RNA; made of nitrogen bases and phosphates carbohydrates large molecules made of carbon, hydrogen, and oxygen, which provide short- term energy for living organisms Interna;onal School of Tanganyika MYP Science 4

5 lipids fawy acids such as oils, waxes, and steroids; insoluble in water proteins DNA large molecules made of long chains of amino acids; an essen;al part of all living organisms, especially as building blocks muscle, hair, collagen, etc., and as enzymes and an;bodies. deoxyribonucleic acid; a long chain of nucleo;des, which contains all the gene;c informa;on about an organism RNA a messenger molecule, which carries instruc;ons from DNA for protein synthesis Interna;onal School of Tanganyika MYP Science 5

6 Levels of Organiza.on molecules groups of atoms covalently bonded together organelles structures within cells which perform specialized func;ons cells smallest single unit of life ;ssues groups of similar cells working together to perform specialized func;ons organs groups of related ;ssues coopera;ng to perform specialized func;ons organ systems groups of related organs coopera;ng to perform one of the MRS GREN func;ons Interna;onal School of Tanganyika MYP Science 6

7 organisms complete living beings, which exhibit all of the MRS GREN characteris;cs popula;ons communi;es ecosystems groups of the same species living in the same place at the same ;me and interac;ng within the groups collec;ons of popula;ons of different species living in the same place at the same ;me and interac;ng with one another living organisms interac;ng with one another and their physical environment terrestrial land- based ecosystems and biomes aqua;c freshwater ecosystems and biomes Interna;onal School of Tanganyika MYP Science 7

8 marine saltwater ecosystems and biomes biomes large geographic areas characterized by similar clima;c pawerns and vegeta;on types tropical temperate polar global biosphere climate zone nearest Earth s equator, characterized by steady day- length and warm temperatures climate zone mid- way between the equator and the poles, characterized by 4 dis;nct seasons climate zone farthest from Earth s equator, characterized by cold temperatures and extremes of day and night all the living organisms on Earth Interna;onal School of Tanganyika MYP Science 8

9 Energy and Nutrient Flows Through Ecosystems Open systems ecosystems have inputs and outputs of energy and mawer transfer movement of energy or mawer from one part of a system to another transforma;on energy or mawer changes state movement of energy enters, passes through, and exits the ecosystem movement of mawer and nutrients cycle repeatedly within the system Interna;onal School of Tanganyika MYP Science 9

10 Thermodynamics Every energy conversion is <100% efficient (some energy is lost) Each trophic level uses some energy for respira;on Higher trophic levels must have less total energy than lower levels Ecological pyramids common structure of all ecosystems Pyramids of numbers tendency of ecosystems to have fewer organisms at each subsequent trophic level Pyramids of biomass tendency of ecosystems to have less living mass at each subsequent trophic level Ecological niches specialized role (func;on) an organism plays within an ecosystem Interna;onal School of Tanganyika MYP Science 10

11 autotrophs (producers) able to make their own food and energy heterotrophs (consumers and decomposers) must get all food and energy from other organisms herbivores (primary consumers) the first trophic level above producers; they eat only producers omnivores (secondary consumers) the second trophic level above producers; they may eat producers and some consumers carnivores (ter;ary consumers) the third trophic level above producers; they generally eat only consumers Interna;onal School of Tanganyika MYP Science 11

12 apex predators (quaternary consumers) the fourth trophic level above producers; they eat only consumers and are not prey to other organisms water cycle precipita;on > infiltra;on and runoff > absorp;on > evapotranspira;on > condensa;on > precipita;on carbon cycle diffusion > fixa;on > respira;on > sedimenta;on > combus;on nitrogen cycle fixa;on > mineraliza;on > nitrifica;on > consump;on and absorp;on > combus;on and denitrifica;on Interna;onal School of Tanganyika MYP Science 12