Blood
Chapter 2.2
Blood
• Blood is a connective tissue
• Consists of plasma, red blood cells, platelets, and white
blood cells.
• Blood carries oxygen and nutrients to the body.
Plasma
• Plasma is the fluid part of the blood.
• Water, minerals, nutrients, sugars, and
other things
Red Blood Cells (RBC’s)
• Erythrocytes
• Take oxygen to every cell in the
body
• Contains Hemoglobin
• Oxygen-carrying protein
There are about one billion red blood cells
in two to three drops of blood. For every
600 red blood cells, there are about 40
platelets and one white cell
Platelets
• Platelets are fragments of larger cells found in the bone
marrow.
• Platelets last 5-10 days, but are extremely important.
• Platelets help stop bleeding by clumping together at the
site of a wound.
White Blood Cells... WBC’s (Most are made in the
bone marrow. Some mature in the lymphatic system)
White blood cells are a line of defense. They
destroy pathogens.
• What is a pathogen?
A pathogen is an infectious agent, or more commonly germ, such as
a virus, bacteria, or fungus that causes disease to its host.
Fighting Pathogens
• White blood cells destroy in various ways:
• Some engulf the invaders
• Some produce antibodies that destroy certain
pathogens
• Some clean up dead body cells.
Body Temperature Regulation
• When your body temperature goes up, blood vessels
enlarge. Why?
• Heat can be transferred to your skin and evaporates.
This cools you down!
Blood Pressure
• Blood pressure is the force
exerted by blood on the walls of arteries.
(Why not veins?)
• Veins are returning blood to the heart. The pressure is
not near as great.
What are the Two numbers in BP?
• BP is usually given in two numbers. EX: 110/70mmHg
• Systolic: Is the pressure exerted in large arteries when
the ventricle contracts.
• Diastolic: Is the pressure exerted on the arteries when
the ventricle is relaxed.
Microscopic
Views
Fish Blood
Bird Blood
Horse Blood
Frog Blood
Cat Blood
Dog Blood
Human Blood
Snake Blood
HIV/ADIS
• HIV is the Human Immunodeficiency Virus.
• Can lead to Acquired Immune Deficiency Syndrome,
or AIDS.
• damages a person’s body by destroying specific blood
cells
• AIDS is the late stage of HIV infection
• when a person’s immune system is severely
damaged and has difficulty fighting diseases and
certain cancers
Toddler Cured of HIV