Cells Cell Organelles The Building Blocks of Life
Cells & Cell Organelles The Building Blocks of Life AP Biology 2008 -2009
Big Questions § What is the relationship between matter § § § and energy Why does life require matter? Why does life require energy? How do the interactions of cellular components allow the cell to process matter and energy? Regents Biology
Life of the Cell must do to stay alive § Process matter: molecules need to be § § acquired, synthesized and digest Process energy: in order to process matter, energy must be provided Process information: instructions that enable the cell to process matter and energy must be interpreted by cellular system. Signals from the environment must also be interpreted Regents Biology
Many cell will also § Reproduce: the information that runs § the cell must be passed onto new generation of cells Communicate: cells respond to/direct other cells § CELLS HAVE SYSTEMS TO DO ALL OF THESE THINGS Regents Biology
Organelles § Organelles do the work of cells u each structure has a job to do § keeps the cell alive; keeps you alive Regents Biology Model Animal Cell
Energy Processing, cells need power! § Energy - ability to do work. Stored in § § chemical bonds. Means: ability to move matter around Examples that required matter movement § § § § take in nutrients (food and O 2) make ATP Breaking molecules down ATP remove waste Reproduction Regulation All life processes Regents Biology
Energy is processed NOT Made. . u Where do cells get energy? § Food and sun (few exceptions) u ATP organelles that do this work… § § Regents Biology lysosomes Vacuoles Mitochondria Chloroplast (plants)
nucleus control cell protects DNA endoplasmic reticulum processes proteins makes membranes ribosomes make proteins cytoplasm central vacuole storage: food, water or waste Golgi apparatus finish & ship proteins cell wall support mitochondria make ATP in cellular respiration cell membrane cell boundary controls movement of materials in & out recognizes signals Regents Biology chloroplast make ATP & sugars in photosynthesis lysosome digestion & clean up
Cells convert incoming energy to forms used using 2 major organelles Mitochondria § Chloroplast and Mitochondria Energy process: & O 2 Respiration From food (glucose) to ATP Heat Chloroplast Energy process: photosynthesis From sunlight to carbohydrates & Regents Biology ATP= contains easily broken bonds (quick energy usage) Adenosine Triphosphate
LYSOSOMES STRUCTURE § Sac of hydrolytic digestive § enzymes low p. H 5 (cytosol p. H 7) FUNCTION (JOB) § Break down food & bacteria § Digestion of damaged cell § § Nucleus parts Apoptosis (Programmed cell death (Think= “Lysol” cleaner Regents Biology 1 µm Lysosome contains active hydrolytic enzymes Food vacuole fuses with lysosome Hydrolytic enzymes digest food particles Digestive enzymes Lysosome Plasma membrane Digestion Food vacuole (a) Phagocytosis: lysosome digesting food
§ Some types of cell can engulf another § § cell by phagocytosis (cells ingest materials); this forms a food vacuole A lysosome fuses with the food vacuole and digests the molecules Lysosomes also use enzymes to recycle the cell’s own organelles and macromolecules, a process called autophagy Regents Biology
Can you guess which of these two white blood cells has bone apoptopic? Hint: an apoptopic cell breaks apart into vesicles called “blebs”. The blebs are AP Biology absorbed by neighboring cells
Apoptosis is responsible for the space between your fingers, nostrils, eyelids, mouth and generally every hole in your body (that’s supposed to be there) AP Biology
AP Biology
A Job for Lysosomes 6 weeks 15 weeks Regents Biology
Lysosomes lysosomes digesting broken organelles small food particle vacuole digesting food Regents Biology
Lysosomal Diseases § Often fatal § Digestive enzyme don’t work § Lysosomal “Storage” disease Lysosome picks up molecules but can’t digest them u Lysosomes fill up, grow larger & larger until disrupts cell & organ function u More than 40 known diseases u Regents Biology
Tay-Sachs Disease § A recessive genetic disease § Undigested fat builds up in brain cells § Mental retardation and death at an early at (by 4) Regents Biology
Peroxisomes: Oxidation § Structure: specialized metabolic § compartments bounded by a single membrane Functions: produce hydrogen peroxide (H 2 O 2 dangerous molecule) u Detoxifies cell, alcohol & other poisons u Breakdown fatty acids to sugars u Regents Biology
VACUOLES- Food & water storage food vacuoles plant cells central vacuole PROTIST animal cells Regents Biology contractile vacuole
Food Vacuoles (animals) § Structure membrane sac u Small u Formed by phagocytosis u § Function small food particle vacuole Food vacuoles: contain undigested food. u Fuse with lysosomes. u digesting food inside cel Regents Biology
CONTRACTILE VACUOLE STRUCTURE § Usually spherical found in FRESHWATER protist Ex: paramecia FUNCTION (JOB) § Pump excess water out of the cell § Regulate water (homeostasis) § Keeps the cell from Regents Biology (bursting) lysing
Central VACUOLES § Fluid filled sacks for storage Plant cells STRUCTURE § large Central Vacuole Surrounded by a membrane called a TONOPLAST § No vacuoles in bacterial cells u Regents Biology
Central VACUOLES (CON’T) FUNCTION (JOB) § In plants, vacuoles store Cell Sap u Includes storage of sugars, proteins, minerals, lipids, wastes, salts, water, and enzymes Regents Biology 24
Mitochondria (produce independently of the cell) § Structure Bean shape u double membrane u Cristae-folded inner membrane u Membrane- contain copies of enzymes needed to produce ATP, with maximized surface area u Matrix- fluid filled inner cavity § Contains DNA, free ribosomes& enzymes in both animal & Regentscells Biology plant ATP
MITOCHONDRION (CON’T) Function Aerobic Cellular Respiration • Digestion (catabolism) of macromolecules to produce ATP, CO 2, and H 2 O • Sugar +O 2 ATP • Fuels the work of life “Powerhouse” of cell More active cells like muscle cells have MORE mitochondria Regents Biology 26
Membrane bound enzymes Regents Biology
CHLOROPLASTS (plants) STRUCTURE § DOUBLE membrane § Thylakoid membrane-contains many copies of enzymes and chlorophyll needed to produce chemical energy from solar radiation § Stroma- internal fluid. Contains DNA, ribosomes& enzymes. Sugar is made § Thylakoids- sacs (“coins”) inside inner membrane. ATP is made. § Granum -Thylakoids stack (pl. =grana) FUNCTION: § Photosynthesis u Building (anabolism) of sugar from ATP, CO 2, & light. u Produces O 2 as waste Regents Biology
Membrane bound enzymes Regents Biology
Chlorophyll § Is a light absorbing pigment molecule that drives § photosynthesis and give plants their green color Chlorophyll needed to produce chemical energy from solar radiation located in thylakoid membrane. Regents Biology
Plants make energy two ways! Mitochondria Chloroplast autotrophs & heterotrophs § autotrophs only make energy from sugar + O 2 § make energy + sugar from Cellular respiration sugar + O 2 ATP + CO 2 + H 2 O § sunlight Photosynthesis § sunlight + H 2 O+ CO 2 ATP + glucose + O 2 u glucose = stored energy u build leaves & roots & fruit out of the sugars Chlorophyll-green pigment that traps light u Regents Biology § ATP = active energy
Mitochondria and Chloroplast contain their own circular DNA and their own ribosomes Regents Biology
Mitochondria and Chloroplast, both: • • • Transform energy generate ATP have double membranes Are semi-autonomous organelles Move, change shape, divide on their own Have small internal ribosomes, circular DNA and make their own protein enzymes • How can we explain these facts? AP Biology
§ The chloroplast is a plastids (class of plant structures) § All plastids are the products of endosymbiosis (DNA § sequence analysis puts plastid ancestors near modern cyanobacteria Plastid is a pigment producing organelle in cells (chloroplast- store chlorophyll, amyloplast- stores starch in roots and chromoplasts- stores pigments for fruits and flowers) Regents Biology
Similar patterns of plastid evolution and diversification are seen in algae too Protists birth of eukaryotes? Primary vs secondary endosymbiosis Regents Biology
§ The endosymbiont theory suggests that an early ancestor of eukaryotes engulfed an oxygen-using non photosynthetic prokaryotic cell § The engulfed cell formed a relationship with the host cell, becoming an endosymbiont § The endosymbionts evolved into mitochondria § At least one of these cells may have then taken up a photosynthetic prokaryote, which evolved into a Regents Biology chloroplast
Endosymbiosis Theory § Mitochondria and chloroplasts were once free living bacteria u Engulfed by ancestral eukaryote § Endosymbiont u Cell that lives within another cell (host) § Partnership § Evolutionary advantage for both w Supplies energy, raw material protection Regents Biology
Endosymbiosis Theory § Endo means within, Symbiosis- relationship § How does endosymbiosis play a role in evolution of prokaryotes to eukaryotes and how is mitochondria impt to evolution? Regents Biology
Endosymbiosis Theory § Endo means within, Symbiosis- relationship § How does endosymbiosis play a role in evolution of prokaryotes to eukaryotes and how is mitochondria impt to evolution? Scientist believe that long ago two separate bacteria (prokaryotes evolved to become eukaryotes. There were free living bacteria that are similar to today’s mitochonderion. Another prokaryote bacteria digested or engulfed the mitochondrion like bacteria and instead of destroying it, it stayed within the bacteria and helped it get energy. After a long time, the two evolved into one leading to the eukaryotic cell. Regents Biology
Endosymbiosis Theory § Endo means within, Symbiosis- relationship § What is the eviden. CE scientist have to support endosymbiosis and the evolution of prokaryotes to eukaryotes? Regents Biology
Endosymbiosis Theory § Endo means within, Symbiosis- relationship § What is the evident scientist have to support endosymbiosis and the evoluton of prokaryotes to eukaryotes? § Mitochondrion has it own membrane, just like prokaryotes has a cell membrane. Mitochondrion has its own DNA, like prokaryotes but smaller. When a cell replicated, the mitochondrion passes on the it DNA separately from the cell’s DNA that is in the nucleus. Mitochondrion reproduce by pinching in half, which is the same way prokaryotes reproduce. Each new mitochondrion must come form another mitochondrion. If a cell were to have all its mitochondria removed, the cell could not make any more Regents Biology
Mitochondria are in both cells!! animal cells plant cells mitochondria Regents Biology chloroplast
Cell Summary § Cells have 3 main jobs u make energy § need food + O 2 § cellular respiration & photosynthesis Our § need to remove wastes u make proteins organelles do all those jobs! § need instructions from DNA § need to chain together amino acids & “finish” & “ship” the protein u make more cells § need to copy DNA & divide it up Regents Biology
cytoplasm jelly-like material holding organelles in place vacuole & vesicles transport inside cells storage mitochondria make ATP energy from sugar + O 2 cell membrane cell boundary controls movement of materials in & out Regents Biology recognizes signals lysosome food digestion garbage disposal & recycling Peroxisome hydrogen peroxide and detoxifies
cytoplasm jelly-like material holding organelles in place vacuole & vesicles transport inside cells storage centrioles cell division lysosome food digestion garbage disposal & recycling chromosomes DNA mitochondria make ATP energy from sugar + O 2 ribosomes builds proteins Peroxisome hydrogen peroxide and detoxifies cell membrane cell boundary controls movement of materials in & out Regents Biology recognizes signals nucleus protects DNA controls cell ER helps finish proteins makes membranes Golgi apparatus finishes, packages & ships proteins
nucleus control cell protects DNA endoplasmic reticulum processes proteins makes membranes ribosomes make proteins cytoplasm central vacuole storage: food, water or waste Golgi apparatus finish & ship proteins cell wall support mitochondria make ATP in cellular respiration cell membrane cell boundary controls movement of materials in & out recognizes signals Regents Biology chloroplast make ATP & sugars in photosynthesis lysosome digestion & clean up
cytoplasm jelly-like material holding organelles in place vacuole & vesicles transport inside cells storage lysosome food digestion garbage disposal & recycling nucleus protects DNA controls cell chromosomes DNA mitochondria make ATP energy from sugar + O 2 cell membrane cell boundary controls movement of materials in & out Regents Biology recognizes signals
cytoplasm jelly-like material holding organelles in place vacuole & vesicles transport inside cells storage mitochondria make ATP energy from sugar + O 2 cell membrane cell boundary controls movement of materials in & out Regents Biology recognizes signals lysosome food digestion garbage disposal & recycling nucleus protects DNA controls cell ribosomes builds proteins
cytoplasm jelly-like material holding organelles in place vacuole & vesicles transport inside cells storage cell membrane cell boundary controls movement of materials in & out Regents Biology recognizes signals
cytoplasm jelly-like material holding organelles in place vacuole & vesicles transport inside cells storage lysosome food digestion garbage disposal & recycling ribosomes builds proteins mitochondria make ATP energy from sugar + O 2 cell membrane cell boundary controls movement of materials in & out Regents Biology recognizes signals nucleus protects DNA controls cell ER helps finish proteins makes membranes
cytoplasm jelly-like material holding organelles in place vacuole & vesicles transport inside cells storage lysosome food digestion garbage disposal & recycling ribosomes builds proteins mitochondria make ATP energy from sugar + O 2 cell membrane cell boundary controls movement of materials in & out Regents Biology recognizes signals nucleus protects DNA controls cell ER helps finish proteins makes membranes Golgi apparatus finishes, packages & ships proteins
nucleolus ribosomal RNA are synthesized and ribosomal subunits are made vacuole & vesicles transport inside cells storage nucleus protects DNA controls cell chromosomes DNA centrioles cell division ribosomes builds proteins cell membrane cell boundary controls movement of materials in & out Regents Biology recognizes signals ER helps finish proteins makes membranes Golgi apparatus finishes, packages & ships proteins
cytoplasm central vacuole storage: food, water or waste cell wall support mitochondria make ATP in cellular respiration cell membrane cell boundary controls movement of materials in & out recognizes signals Regents Biology chloroplast make ATP & sugars in photosynthesis lysosome digestion & clean up
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