Cell structure and function

Prokaryotic cells lack nucleus and are the kind of cells that bacteria and archea have.

Eukaryotic cells have organelles including a nucleus where DNA is located. Protist, fungi, plants, & animals are made from eukaryotic cells…

ATP is used by all types of cells as their basic energy source

Cellular respiration Cellular respiration is the process that release energy by breaking down glucose and other food molecules in the presence of oxygen. There are three steps: –Glycolysis –Kreb’s cycle –Electron transport chain

Cellular respiration How much energy is present in food? –Quite a lot. One gram of the sugar glucose, when burned in the presence of oxygen, releases 3811 calories of heat energy. –Calorie is the amount of energy needed to raise the temperature of one gram of water one degree celcius. –This process begins with a pathway called glycolysis (Greek: sugar splitting). If oxygen is present, then two more steps follow. If NO oxygen is present, then lactic acid is made –This is why muscles hurt during extraneous workouts.

How efficient is cellular respiration? The 36 ATP molecules the cell makes per glucose represent about 38% of the total energy of glucose. That might not seem like much, but it means that the cell is actually more efficient at using food than the engine of a typical automobile. What happens to the remaining 62%? –It is released as heat, which is one of the main reasons why we are warm to the tough – especially after working-out.

Questions?