Fluids Pressure and Circulation Chapter 11
Fluids • Fluids are part of your body • Fluid is a material that can easily flow , such as a gas or a liquid. • Fluids flow to fit the shape of containers
Fluids • Examples: • Cytoplasm • Blood • Liquid in joints
Fluids • Fluids push in all directions • This pushing means that there is a force that is exerted • This force is not applied in just one place but is spread over an area
Pressure • Pressure is a measure of how much force is acting on a certain area • Air moves from areas of higher to lower pressure when you breathe • In what directions do fluids push?
Pressure • All
Pressure • When you breathe out the volume of the lungs becomes smaller so the air is compressed and the air in your lungs is at a higher pressure. • Explain this.
Pressure • To fill your lungs you inhale using a muscle called the diaphragm
Pressure • How to measure pressure • Pressure is measured in Pa (Pascal) • Force is measured in N (newton) • Area is measured in m2 (square meters) • P= F/A
Pressure • Questions
Fluids and Pressure • Fluids spread out. So the pressure is greater next to the force, but is less greater away from the force.
Section 2 Blood: Circulatory System • Pressure and Fluids in the Circulatory System
Circulatory System • Blood moved around the body
Blood • A fluid that circulates the body • Blood is made of Red and White cells • These cells are carried in liquid called plasma • Plasma is made of water, proteins, and glucose
Blood and the Heart • There are two circuits that the heart pumps • Pulmonary Circuit • Systemic Circuit
Pulmonary Circuit • Blood goes to the lungs and back to the heart
Systemic Circuit • Blood goes to the body and back to the heart
How the heart pumps • The heart pumps using • Arteries • Capillaries • Veins
Arteries • Blood leaving the heart is at high pressure so the artery wall must be thick
Capillaries • Smallest blood vessels
Veins • The blood pressure is lower than in arteries
How the heart pumps • See diagram
Functions of Fluids • Divert and Spread forces • Support • Transport materials • Lubricate • Block Materials
Functions of Fluids • Divert and spread forces • Fluid in a blister spreads a damaging force to a larger area and so reduces further damage
Functions of Fluids • Support • Fluid pressure inside cells makes the cells firm
Functions of Fluids • Transports materials • Flowing blood carries nutrients to cells and waste away from cells
Functions of Fluids • Lubricate • Tears help the eyelids glide more easily
Functions of Fluids • Block materials • Tears help keep dust from reaching the eye’s surface and also keep the surface from drying out
Our Senses and Fluids • Mouth- Saliva moves materials from your taste buds • Nose- Mucus helps move materials to cells to detect smells • Ear- helps us with our balance • Eye- sight
The Ear • Three ear cavities help you with position and motion • Semicircular Canals
The Ear • The outer and middle part of the ear is filled with air • The innermost ear and semicircular cannals have liquids.
The Eye • Tears: Flow outside the cornea • Aqueous humor: is a fluid that transports nutrients to the lens and cornea and carries away wastes
Organ Systems and Fluids • Circulatory and Lymphatic System • Respiratory System • Digestive and Urinary System • Nervous System • Reproductive System • Muscular and Skeletal Systems