Cellular Respiration

The transfer of stored energy in food molecules to a form usable by the organism Involves the exchange of gases between the organism and the environment

Process Through the process of respiration, the organism produces adenosine triphosphate (ATP) which will be used for energy

1. Cellular Respiration Involves a series of enzyme-controlled reactions in which energy in food is broken down into energy that the organism can use (ATP)

a) When ATP is broken down, energy is released and ADP is formed ADP = adenosine diphosphate H 2 O + ATP  ADP + P + energy This is the energy used by the body to carry out the functions of life

Types of Respiration 1. Aerobic Respiration -involves the use of oxygen 2. Anaerobic Respiration -oxygen is not used

Anaerobic Respiration Also known as Fermentation Does not require oxygen Takes place in the cytoplasm of cell Glucose is either broken down into lactic acid or alcohol and CO 2 As a result of anaerobic respiration, there is a net gain of 2 ATP’s

Equations for Anaerobic Respiration glucose  2 lactic acids + 2 ATP’s glucose  2 alcohol + 2 CO ATP’s In each equation, enzymes are used and a net gain of 2 ATP’s are produced

Anaerobic Respiration Glucose Pyruvic acid +2 ATP Lactic Acid 4 ATP “Lactic Acid Fermentation” “Lactic Acid Fermentation

Anaerobic Respiration Glucose Pyruvic acid +2 ATP Alcohol + CO 2 4 ATP “Alcoholic Fermentation”

Aerobic Respiration Requires oxygen Takes place in the mitochondria When we say that glucose is oxidized, we say that it is broken down with the help of oxygen molecules

Equation for Aerobic Respiration glucose + O 2  H 2 O + CO ATP’s Again, enzymes are used and a net of 36 ATP’s are produced

Aerobic Respiration Glucose Pyruvic acid -2 ATP +4 ATP + O2O2 Water + CO ATP ***Net Gain = 36 ATPs***

Summary Anaerobic Respiration = 2 ATP’s Aerobic Respiration = 36 ATP’s Therefore, Aerobic respiration is more efficient than anaerobic respiration

Adaptations for taking in gases and materials for Cellular Respiration

Monera, Protista, and Fungi Gas exchange occurs by diffusion through a thin, moist cell membrane

Plants Leaves- have stomates for gas exchange Stems- have lenticels for gas exchange, and xylem and phloem for transport of materials. Roots- gas exchange occurs across a moist membrane of root hairs (diffusion)

Hydra Each cell of the hydra is in contact with the watery environment and gas exchange occurs by diffusion

Earthworm Secretes mucus on skin to keep it moist The moist surface allows the diffusion of gases through the skin and into and out of the blood (capillaries) Blood in the capillaries “pick up” the oxygen and transport it to the cells of the organism. Hemoglobin aids in the transport of oxygen to body cells.

Grasshopper Blood does not play a role in the transport of oxygen or carbon dioxide (no hemoglobin) Gas exchange and transport is accomplished by tracheal tubes. Access to tracheal tubes is through the spiracles. Spiracles are openings located on the tracheal tubes that allow for gas exchange between the organism and the environment. Once oxygen is in the tracheal tubes, it diffuses through the moist membrane of the tube and into the cells.

Human Respiratory and Circulatory Systems