17 terms

Bio Ch. 6

Slow Fibers
- sustain repeated contractions but don't generate a lot of quick power for body
- long distance running
- aerobically= using oxygen
Fast Fibers
- contract more quickly and powerfully
- fatigue easily
- function with short bursts of energy such as sprints and weights
- anaerobically= WITHOUT using oxygen
- thicker
Cellular Respiration
- the aerobic harvesting of energy by muscle cells (or other cells)
- yields O2, H20, and large amounts of ATP
- perfect for long term muscle contraction
- exergonic
- banks energy in ATP molecules
- 38 ATP
-40% of a glucose molecules potential energy
- 3 main stages (glycolysis, citric acid cycle, oxidative phosphorylation)
- water and CO2 also produces
Energy Necessary for Life
1. growth, transport
2. manufacture, movement
3. reproduction, and others
- Energy that supports life on Earth is captured from sun rays reaching Earth through plant, algae, protist, and bacterial photosynthesis
- Energy in sunlight is used in photosynthesis to make glucose from CO2 and H2O with release of O2
- Cellular respiration uses O2 and energy in sugar and releases CO2 and H20
Breathing and Cellular Respiration
- breathing supplies O2 to our cells for use in cellular respiration and removes CO2
- provides an exchange
kilocalories (kcal)
- is the quantity of heat required to raise the temperature of 1 kilogram (kg) of water by 1 degree C
- used for body maintenance and voluntary activities
- adult needs about 2,200 kcal per day
Redox reaction
- movement of electrons from one molecule to another
- oxidation= loss of electrons from one substance
- reduction= addition of electrons to anothher substance
- cellular respiration
Cells tap energy from electrons "falling" from organic fuels to oxygen
- The energy necessary for life is contained in the arrangement of electrons in chemical bonds in organic molecules
- When the carbon-hydrogen bonds of glucose are broken, electrons are transferred to oxygen
- oxygen is a strong attraction to electrons (lose potential enegry)
- dehydrogenase removes electrons in H atoms from fuel molecules (oxidation) and transfers them to NAD+
- NADH passes electrons to an electron transport chain
- electrons fall from carrier to carrier and finally to O2, releasing energy in small quantities
- if energy released by being burnt, it dissipated as heat and light which is unavaliable
- occurs in cytoplasm
- begins respiration by breaking glucose, a six-carbon molecule, into two molecules of a three-carbon compound called pyruvate
- yields 2 ATP and 2 NADH
- small amounts of ATP
Citric Acid Cycle
- occurs in mitochondria
- breaks down pyruvate into carbon dioxide and supplies the third stage with electrons
- 2 carbons enter the cycle through acetyl CoA,
- 2 CO3, 3 NADH, 1 FADH2, and 1 ATP exit the cycle
- turning of cycle repeats
- small amounts of ATP
Oxidative Phosphorylation
- occurs in the inner mitochondrion membrane
- During this stage, electrons (NADH and FADH2) are shuttled through the electron transport chain
- picks up H+ to form water
- energy released by these redox reactions is used to pump H+ into the space between the membranes of mitochondrion
- As a result, ATP is generated through oxidative phosphorylation associated with chemiosmosis (H diffuses back across inner membrane down its concentration gradient, leading to ATP synthesis)
- large amounts of ATP
- uses oxygen ti extract chemical energy from organic compounds
- potential energy of this concentration gradient( of H+) is used to make ATP
ATP synthases
- protein complexes built into the inner membrane that synthesis ATP
- concentration gradient drices the diffusion of H+
Substrate-level phosphorylation
- an enzyme transfers a phosphate group from a substrate molecule directly to ADP forming ATP
- prduces small amounts of ATP in glycolysis and citric acid cycle
Acetyl CoA
- high-energy fuel molecule for the citric acid cycle
- pyruvate is chemically groomed for the citric acid cycle, what its converted to
- enables cells to produce ATP without oxygen
- anaerobic(without oxygen) energy generating process
- muscle cells, cheeses, yeasts, yogurt, alcohol
- NAD+ is recycled from NADH as pryvate is converted to lactate or alcohol/CO2
- lactic= muscles
- alcohol= winemaking, brewing, baking
*yeasts= single celled fungi normally use aerobic respiration
* CO2 provides bubbles in champaigne
Three other sources for generation of ATP
1. carbs
2. proteins
3. fats
- use some food molecules and intermediates from glycolysis and citric acid cycle as raw matierals