Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
34 Cards in this Set
- Front
- Back
|
cellular respiration
|
O2 is taken up by breathing and transported to the cells by blood flow
CO2 is removed by blood flow food and wastes are also transported by blood flow |
|
|
what is needed for MOST cellular metabolism
|
oxygen
|
|
|
efficiency of energy use
|
ratio of energy actually used to the total amount available at start
|
|
|
efficiency of cellular respiration
|
Some energy is always lost during conversion from one form to another
|
|
|
gasoline engines efficiency
|
25%
|
|
|
energy available in glucose is used to make ATP
|
40%
|
|
|
energy in glucose molecule is lost as heat
|
60%
|
|
|
cell use energy..
|
Just to stay alive
To change shape (e.g.,muscle cells) And to grow, heal, etc. |
|
|
where energy comes from
|
Food is broken down to glucose and other molecules
Energy from these molecules is used to make ATP molecules in every cell During metabolism, ATP molecules are broken down to release energy (then ADP gets recycled) |
|
|
how cells harvest energy
|
Cells tap the energy stored in chemical bonds,but energy stored in chemical bonds of glucose is too much for cellular functions so cells need to harvest the energy in small steps. Each step involves electrons being transferred from one molecule to another with a slightly lower energy level
|
|
|
energy in electron transfer
|
A small amount of energy is released in each electron transfer
Some energy is lost as heat in each step. The energy released is used to make ATP molecules |
|
|
1st stage of respiration (exergonic)
|
Glycolysis (anaerobic, in cell cytosol)
Glucose breakdown into pyruvic acid Occurs in cytoplasm |
|
|
2nd stage of respiration (exergonic)
|
Krebs cycle (aerobic, in mitochondria)
Further breakdown of pyruvic acid derivative Occurs in mitochondria |
|
|
3rd stage of respiration (endergonic)
|
Electron transport chain (anaerobic in mitochondria)
|
|
|
slide 31 and 32 ch 7
|
glucose metabolism picture
|
|
|
slide 33 ch 7
|
chart
|
|
|
glycolysis (sugar-splitting)
|
Occurs in cytoplasm in all living cells
Starts with 1 molecule of glucose 9 intermediate steps 4 are endergonic 5 are exergonic Ends with 2 molecules of ATP (5% of useable energy from glucose) 2 molecules of NADH (16% of energy) 2 molecules of pyruvic acid (79% of energy—later used for electron transport chain) |
|
|
slide 35 ch 7
|
another picture
|
|
|
glycolysis to krebs cycle
(picture on slide 36 ch 7) |
2 molecules of pyruvic acid from glycolysis- Diffuse into mitochondria then are broken down further and the energy harvested from this breakdown is used to fuel Krebs cycle
|
|
|
slide 37 ch 7
|
kreb's cycle diagram
|
|
|
Kreb's cycle completes
|
glucose breakdown but not ATP synthesis
|
|
|
Kreb's cycle
|
named after Hans Krebs
Occurs in mitochondria only in eukaryotes Starts with 2 molecules of pyruvic acid derivative (2 molecules of Acetyl CoA) 5 major intermediate steps Ends with 2 ATPs from substrate-level phosphorylation(5% of useable energy from glucose molecule) 6 NADH (48% of energy—later used in electron transport chain) 2 FADH2 (10% of energy—later used in electron transport chain) |
|
|
slide 30 ch 7
|
another diagram of Kreb's cycle
|
|
|
Electron transport chain completes
|
respiration and ATP synthesis
|
|
|
electron transport chain
|
Last step of cellular respiration
Occurs in mitochondria Starts with NADH – from glycolysis & Krebs cycle FADH2 – from Krebs cycle Ends with about 32/34 ATPs (17 times as many as glycolysis alone) |
|
|
slide 41 ch 7
|
diagram of electron transport chain
|
|
|
chemiosmosis
|
Major mechanism of ATP production
|
|
|
Summary of cellular respiration
|
-glycolysis breaks down glucose in cytoplasm
-Pyruvic Acid from glycolysis diffuses into mitochondria (gets broken down further) -Krebs cycle occurs in mitochondria Starts with pyruvic acid derivative (Acetyl CoA) and produces some ATP and lots of NADH & FADH2 -Electron transport chain occurs in mitochondria -Uses NADH & FADH2 and produces CO2, H2O, and lots of ATP |
|
|
anaerobic metabolism
|
metabolism without oxygen
|
|
|
oxygen requirement
|
Glycolysis (in cytosol) does not require oxygen
But Krebs cycle (in mitochondria) requires oxygen |
|
|
fermentation produces
|
alcohol (by yeasts: wine, beer, breads)
lactic acid (by many kinds of cells: muscle fatigue) |
|
|
When oxygen not available for Krebs cycle
|
cells use anaerobic metabolism
|
|
|
organic molecules used for energy
|
-Polysaccharides broken down into glucose for starch in plants and glycogen in animals
-Fats broken down into glycerol for intermediate step of glycolysis and fatty acids which are used to make Acetyl CoA -Proteins are broken down into amino acids which are used in Krebs cycle |
|
|
biosynthesis
|
making of new organic molecules
|
