Ch. 4 Cells and Energy Photosynthesis and Cellular Respiration 1
2 4.1 Chemical Energy and ATP Living organisms need energy Most comes indirectly from sun! Some change sunlight into organic compounds Others use organic compounds as food
Food Chain Energy flow between organisms 3
4 ATP Adenosine triphosphate Energy Currency Made in mitochondria Useable energy Glucose ATP
5 Components of ATP - Adenosine - Includes ribose (sugar) - adenine - Three phosphate groups
6 ADP Adenosine diphosphate Lower energy than ATP Made when Phosphate group released from ATP Can be converted back to ATP Complex process
7 Cell Energy All cells need energy Plant Animal Fungi Protists Bacteria Use energy to: Grow Live Reproduce
8 Carbon-based Molecules Food is broken down Digestion Useable molecules Different food = different # ATP
9 Carbohydrates Not stored in large amounts in body Broken down to glucose 1molecule can yield ~36 ATP If not used, stored as glycogen
10 Calories per Gram Calorie = unit for energy from food Carbohydrate 4 calories Protein 4 calories Lipid 9 calories
11 Lipids Store the most energy ~80% of energy in body Provide most ATP 1 triglyceride = ~146 ATP molecules!
12 Protein Same amount of energy as carbs Not likely to be used as ATP Need aa for protein making in body
13 Autotrophs Producers Use sunlight or inorganic compounds to make own food Make organic compounds Most use photosynthesis Ex: Plants
14 Heterotrophs Consumers Cannot make food Eat other organisms
15 Autotrophs and Heterotrophs
16 Chemosynthesis Process by which some organisms use chemical energy rather than sunlight to make food Ex: organisms by hydrothermal vents Use sulfides for energy source Still need ATP
17 4.2 Photosynthesis Photo = light Synthesis = putting together Chemical rx occurs in chloroplasts Chloroplasts contain chlorophyll
18 Photosynthesis Sunlight used to make sugar used to store chemical energy Sunlight Ex: Plants Sugar Algae (Protists) Some bacteria
19 Photosynthesis sunlight 6 H 2 O + 6 CO 2 ----------> C 6 H 12 O 6 + 6 O 2 Reactants: Water Carbon dioxide Products: Glucose Oxygen
20 Chlorophyll Molecules that absorb light energy Absorbs blue and red Reflects green and yellow Why plants look green 2 types: Chlorophyll a Chlorophyll b In chloroplasts
21 Carotenoids Pigments that produce yellow and orange leaf colors Absorb different wavelengths than chlorophyll
22 Photosynthesis occurs in Chloroplasts Light dependent reactions Light Independent reactions
23 4.3 Photosynthesis Stages 1) Absorption of light energy Chloroplasts Light dependent Light independent 2) Conversion of light energy e - transport chain 3) Storage of energy Calvin cycle dark rx ; CO 2 fixation
25 Factors that affect photosynthesis Sunlight CO 2 Concentration Temperature Growing plants in space ~3 min http://www.teachersdo main.org/asset/npe11_ vid_plants/
26 Getting Energy from Food Cellular respiration Uses oxygen = aerobic Releases energy from food Fermentation Does NOT use oxygen = anaerobic Releases energy from food
27 4.4 Cellular Respiration Chemical rx Occurs in mitochondria Converts glucose into ATP Occurs in ALL organisms
28 Respiration Equation Review Requires O 2 and glucose Gives off CO 2 and H 2 O Useable cell energy Forms ATP
Cellular Respiration Eukaryotic Cells: Occurs in the mitochondria Prokaryotic Cells: Occurs in cell membrane 29
4.5 Before Cellular Respiration Glycolysis Breakdown of Glucose Anaerobic In cytoplasm Ongoing Net yield: 2 ATP molecules
31 Stages of Cellular Respiration o 1) Krebs Cycle o Citric Acid Cycle o Follows glycolysis o Produces CO 2 o In Mitochondria o Net 2 ATP o 2) e- transport chain o Net 34 ATP
Net ATP Yield 1 molecule of Glucose can yield UPTO 38 ATP - 2 from glycolysis - 36 from cellular respiration * 2 from Krebs cycle * 34 from e- transport chain
33 4.6 Fermentation Does NOT make ATP Allows glycolysis to continue Anaerobic
34 Fermentation in Muscle Cells Cells can t get enough oxygen for cellular respiration Use fermentation Produces lactic acid = C 3 H 6 O 3 Causes muscle fatigue Burning sensation
35 Fermentation in Yeasts Alcoholic fermentation Gives off CO2 Causes bread to rise Leaves small holes Produces ethanol in wine and beer
36 Photosynthesis and Cellular Respiration