Bio exam 2, last 2 slide shows

digestion breaks food down to basic monomers

1. monosacharides
2. fatty acids
3. amino acids
4. nucleotides


dont require oxygen
completed in cytoplasm
ex. fermentation


require oxygen
completed in mitochondria


starts from a simple Glucose "sugar"
breaking of the covalent bonds releases energy
occurs in cytoplasm

two types of glycosis

energy requiring 2 atp needed
non requiring
2 nahd formed
4 atp created

What is Acetyl-CoA

A two-carbon acetyl group linked to coenzyme A (a derivative of the B vitamin Pantothenic Acid

krebs cycle

occurs in the mitochondria
Pyruvate is broken down to CO2
More ATP is formed
More NADH and FADH2 are produced

Electron Transport Phosphorylation

Occurs in the mitochondria
NADH & FADH2 deliver electrons to electron transport systems
O2 receives the electrons to make H2O
Electron transport sets up H+ ion gradients
Flow of H+ down gradients powers ATP formation

Importance of Oxygen

Electron transport phosphorylation requires the presence of oxygen
Oxygen withdraws spent electrons from the electron transport system, then combines with H+ to form water

Fermentation Pathways

type of anerobic pathway
Begin with glycolysis
Do not break glucose down completely to carbon dioxide and water
Yield only the 2 ATP from glycolysis
Steps that follow glycolysis serve only to regenerate NAD+

Anaerobic Electron Transport

Carried out by certain bacteria
Electron transport system is in bacterial plasma membrane
Final electron acceptor is compound from environment (such as nitrogen), NOT oxygen (NOTE - Not the Same as Respiration!!!)
ATP yield is low

Functions of Blood

Transports oxygen and nutrients to cells
Carries carbon dioxide and wastes away from cells
Helps stabilize internal pH
Carries infection-fighting cells
Helps equalize temperature

Composition of Blood

Plasma (50-60% by vol.)
Water 91-92%
Proteins: albumin, antibodies, etc.
Solutes: ions, sugars, fats, amino acids, hormones, vitamins, gasses
Cellular portion (40-50%)
RBC's: O2 and CO2 exchange
WBC's: immune responses
Platelets: blood clotting

A. Human Heart

Double Pump:
Partition separates heart into left and right sides
atrium: receive blood from veins
ventricles: push blood into arteries
Each pumps blood through a different circuit

Each side has two chambers

upper atrium and lower ventricle

Cardiac Cycle

blood enters atria then ventricles
1st atria
2nd ventricle
pushes blood out

Pulmonary Circuit

Short loop that oxygenates blood

Systemic Circuit

Longer loop that carries blood to and from body tissues

Hepatic Portal System

Carries blood from capillaries in digestive organs to capillaries in the liver
Allows liver to detoxify substances from digestive tract before they are carried to the body

Out-flow vessels

Arteries: main transporters of oxygenated blood
Arterioles: diameter is adjusted to regulate blood flow
Capillaries: diffusion occurs across thin walls

Lymphatic System

Absorb water and plasma proteins from tissues and return it to the heart (leaked out from blood capillaries)
Absorbs fats from small intestines and transfer to general circulation
Carries pathogens and foreign cells to lymph nodes (disposal cen

Lymphoid Organs

Central to the body's defense
Thymus gland


Movement of fluid or air around gas exchanging tissues
Removes low O2/high CO2 fluid or air; replaces with high O2/low CO2 fluid or air
Maintains steep gradient so concentration differences are high

Respiratory Cycle

Diaphragm constricts
External intercostal muscles contract
Volume of thoracic cavity increases; pressure decreases
Lungs expand
Air flows down pressure gradient into lungs