Honors Bio: Cytology 3 Pt. 1

Mitochondria

“powerhouse” of the cell

number of mitochondria depends upon energy requirements (function of cell)

Structure of Mitochondria

double membrane

cristae

matrix

ribosomes

mitochondria DNA

Cristae

infolding of the inner membrane, holds enzymes needed by the cell to produce energy

Matrix

soup-like mixture of chemicals needed for energy production

Why is mitochondria folded?

to increase the surface area and hold more enzymes to produce more energy

Function of Mitochondria

to produce the energy needed for all cellular activities through cellular respiration

Cellular Respiration

a biochemical process used to extract energy found in the chemical bonds of food (C-C and C-H bonds) and convert it into an energy storage molecule that can be used for all cellular activity

ATP

adenosine triphosphate

“universal energy storage molecule”

High Energy Bonds

can store more energy than normal covalent bonds

Anaerobic Respiration

doesn’t use oxygen to break down food bonds to get energy

Alcohol Fermentation

enzymes in yeasts/bacteria convert sugars (glucose) to ethanol, carbon dioxide, and a small amount of ATP

Why can’t you “burn” bonds without oxygen?

inefficient breakdown of sugar to ethyl alcohol still has unbroken C-C and C-H bonds

energy production is sufficient for simple organisms

Lactic Acid Fermentation

used by some bacteria and fungi in fermented dairy products and vegetables, produces sharp/sour flavor

when muscle cells try to supply more energy for strenuous activity than your oxygen supply will allow

“Soreness/fatigue”

lactic acid builds up in muscle cells

Oxygen Debt

lactic acid must be burned off by continued “heavy breathing”

Aerobic Respiration

uses oxygen to “burn” food bonds to release energy

6CO2 + 6H2O (products/waste)

complete breakdown of “energy-containing” C-C and C-H bonds

the more energy produced, the more active an organism can be

more energy can be devoted to facing environmental change (warm blooded animals)

Glycolysis

“destruction/splitting of sugar”

initial breakdown of glucose without use of oxygen

occurs in cytosol

2 APT net gain

NAD+/NADH

Nicotinamide Adenine Dinucleotide

Kreb Cycle (Citric Acid Cycle)

occurs in the matrix of the mitochondria

produces CO2

2 ATP net gain

FAD

Flavin Adenine Dinucleotide

Electron Transport Chain (ETC)

occurs on the inner membrane of mitochondria

four protein complexes in membrane use energy from electrons to pump H⁺  (obtained from the electron/hydrogen carriers)  into outer compartment of mitochondria to establish a concentration gradient of H+

32 ATP net gain

ATP synthase

H+ between the inner and outer membrane of the mitochondria fall back into the matrix from “high” to “low”

charges up ADP to ATP

Ribosomes and Mitochondria DNA

have the ability to self replicate

ADP

adenosine diphosphate

AMP

adenosine monophosphate

NAD/FAD

electron/hydrogen carrier molecules

Cellular respiration Equation (→)

C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP

Lactic Acid Formula →

Glucose → (enzymes) Lactic Acid + 2CO2 + 2 ATP

Alcohol Fermentation Equation →

glucose → 2 ethyl alcohol + 2CO2 + 2 ATP

Aerobic Respiration →

C6H12O6 + 6O2 → 6CO2 + 6H2O + 36 ATP

What do some of the H+ and electrons combined with oxygen in the matrix produce? (happens in ETC)

Water