How Cells Gain Energy From Food

Transcription

1 How Cells Gain Energy From Food

2 Aerobic Cellular Respiration How cells harvest energy (ATP) from organic molecules (food) using oxygen

3 Cellular respiration requires cells to take in oxygen & glucose & release wastes in the form of carbon dioxide & water This is why we breathe & eat!!

4 Strokes and heart attacks occur when brain and heart cells are deprived of energy and oxygen

5 Why is oxygen important to aerobic cellular respiration? Where did the hydrogens (electrons) in glucose go?

6 These electrons (hydrogens) hold energy (high energy electrons) What type of energy are they holding? When electrons (hydrogens) change partners, from sugar to oxygen, energy is released Electrons (hydrogens) are strongly attracted to oxygen

7 When electrons (hydrogens) change partners, from sugar to oxygen, energy is released Electrons (hydrogens) are strongly attracted to oxygen

8 Why is oxygen important to aerobic cellular respiration?

9 How do high energy electrons (hydrogens) make their way from glucose to oxygen? Electrons (hydrogens) are carried to oxygen by electron carriers called NAD+ and FAD NAD+ accepts electron (hydrogen) and becomes NADH. FAD accepts electrons (hydrogens) and becomes FADH2 Electrons carried by electron carriers are taken to the electron transport chain

10 Cristae inner membrane Matrix inner space Mitochondria Anatomy

11 4 Steps of Aerobic Cellular Respiration

12 4 Steps of Aerobic Cellular Respiration Glycolysis = more ancient; least efficient step (found in all organisms) Other steps = evolved later; are more efficient (not found in all organisms)

13 Glycolysis Sugar Splitting Location of this step?

14 Glycolysis Sugar Splitting INPUTS? OUTPUTS?

15 Glycolysis Sugar Splitting Does this step require oxygen? Supplies energy for short bursts of activity This is the sole source of energy for some bacteria & one-celled eukaryotes

16 Location of this step? Intermediate Step

17 Intermediate Step INPUTS? OUTPUTS?

18 Krebs (Citric Acid) Cycle Location of this step?

19 Krebs (Citric Acid) Cycle INPUTS? OUTPUTS?

20 Electron Transport Chain Location of this step?

21 Electron Transport Chain INPUTS? OUTPUTS?

22 What is the final electron acceptor? What does it produce once it accepts the electrons?

23 Strokes and heart attacks occur when brain and heart cells are deprived of energy and oxygen

24 It takes about 10 million ATP molecules per second to power an active muscle cell!

25 Aerobic Cellular Respiration Review

26 Energy from Food

27 Anaerobic Cellular Respiration (Fermentation) The harvesting of chemical energy (ATP) from organic fuel molecules (food) without using oxygen What step in aerobic cellular respiration is the most ancient, occurs outside the mitochondria, and does not require oxygen? How much ATP does this step produce, a little or a lot? What kind of organisms can do this and why would they do this?

28 Fermentation in Microbes (Ex. Yeast) What waste products are produced when yeasts only use glycolysis to produce their ATP? How do we take advantage of these waste products?

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30 Fermentation in Muscle Cells lactate During quick bursts of energy use, oxygen cannot be delivered into muscle cells fast enough, so they turn to glycolysis to supply ATP. What waste product is produced when muscle cells only use glycolysis to produce their ATP?

31 Energy & Exercise

32 Cellular Respiration & Metabolic Rates Ectothermic animals internal body temp. is controlled by temp. of environment Examples??

33 Are they able to internally regulate their body temperature? Do they exist at same temperature as their surroundings? How do they obtain their body heat? How is metabolic rate (activity level) affected when environmental temperature changes?

34 How will the process of cellular respiration be affected when it is in a warm environment? When in a cold environment?

35 Cellular Respiration & Metabolic Rates Endothermic internal temp. is controlled by internal metabolism Examples??

36 Are they able to internally regulate their body temperature? Do they exist at same temperature as their surroundings? How do they obtain their body heat? How is metabolic rate (activity level) affected when environmental temperature changes?

37 How will the process of cellular respiration be affected when it is in a warm environment? When in a cold environment?

38 Advantages & Disadvantages of Being Ecto & Endothermic Being Ectothermic? Being Endothermic?

39 Characteristics and activities that ectotherms have and use to help them increase their activity levels?

40 Characteristics and activities that endotherms have and use so that they don t have to use so much energy all of the time?