BMS 108 lecture #4 H. Rose
Ch 4 Enzymes
that speed up chemical reactions
Act by lowering energy of activation
Amount of energy that must be absorbed to start a chemical
Energy must be absorbed to weaken bonds in reactant
We will learn the mechanisms
by which the body maintains
In science how do we determine How Things Work?
In science how do we determine: How Things Work
Homeostasis: The Foundation of Physiology
Physiology is the study of body functions. There are two processes to explain body functions. They are:
teleological - Or WHY-this explanations are in terms of meeting a bodily need. mechanistic - Or HO
Energy Balance and Temperature Regulation
Energy balance is the concept that states: Body weight will remain constant if energy in (calories consumed) = energy out (calories expended). This is also called neutral energy balance.
Fluid and Acid-Base Balance
Cells exist in a tightly controlled environment the ECF
Maintaining the homeostasis of the ECF also maintains the life support fluid of the cells. Both the fluids & the substances in it must be tightly controlled. A
The Urinary System
The Urinary System is important in helping to maintain internal homeostasis.
It helps maintain:
Water, plasma, & ECF volume Electrolyte composition pH Balance Eliminates wastes from the body
The kidneys (controlled by neura
The Endocrine System
The Central & Peripheral Endocrine Glands
The Endocrine System: An Overview
The endocrine system consists of a number of specialized tissues called: Endocrine Glands. The endocrine glands form a system designed for homeost
The Respiratory System
The Respiratory System has two Major Responsibilities
Supply the blood (and ultimately the tissues) with O2. Remove CO2 Simply stated: Respiration involving breathing O2 in and expelling CO2. However, it's more complicate
The blood is the medium for the transport of substances around the body.
The blood is composed of:
Mostly water-plasma 54-58% Red blood cells (41-45% Everything else (WBC's, plateletes, proteins, etc) 1%
Plasma = 55% of whole blood
The Circulatory System
Three main parts/components 1. A pump The heart 2. Blood The medium for carrying nutrient, gases and wastes. 3. Delivery, exchange and return system The arteries, capillaries and veins
The heart e
There are three kinds of muscle tissue: skeletal, cardiac, and smooth.
These three kinds of muscle tissue compose about 50 percent of a human's body (nonwater) weight. Skeletal muscle tissue is striated (lined) and subject to
The Peripheral Nervous System: Efferent Division
Send signals from (Exit) the CNS out to effector organs (muscles & glands) Two branches of the Efferent Division The Autonomic Branch The Somatic Branch
THE AUTONOMIC NS
The Peripheral Nervous System
The Peripheral Nervous System is divided into two divisions: Afferent & Efferent
The Afferent Division is also called the: Sensory Division Remember: Afferent signals are sent At (towards) the CNS
The PNS nerve fibe
The Central Nervous System
DIVISIONS OF THE NERVOUS SYSTEM
2 PARTS OF THE NERVOUS SYSTEM
THE CENTRAL NERVOUS SYSTEM
THE PERIPHERAL N.S.
2 PARTS OF THE PERIPHERAL N.S.
THE AFFERENT DIVISION (INFO TO [AT] THE CNS)
THE EFFERENT DIVISION (INFO
Nerve and muscle tissues are excitable.
They can undergo rapid changes in their membrane potentials. They can change their resting potentials into electrical signals.
NERVE CELLS USE THESE SIGNALS TO:
INITIATE RECEIVE PROCES
The Plasma Membrane and Membrane Potential
The Plasma Membrane is a Bi-layer structure
The membrane has a phosphate head & tail with a lipid center. The gives the membrane its distinctive appearance.
Head (polar, hydrophilic
The cell theory has six principles.
The cell is the smallest structural and functional unit capable of carrying out life processes. The functional activities of each cell depend on the specific structural properties of the c