CHAPTER 30CIRCULATORY & RESPIRATORY SYSTEMSMr. TaylorBiologyRainier Jr/Sr High School

CIRCULATORY SYSTEM Blood vessels and a muscular pump (heart) Transports

1. Nutrients from digested food2. Oxygen (O2) to all cells3. Metabolic wastes (CO2, urea, creatinine, etc.) to

excretory organs4. Hormones5. Distributes heat (both conserving and radiating)

BLOOD VESSELS (VASCULAR ORGANS)1. Arteries carry blood away from the heart.

a) Endothelium; inner liningb) Elastic fibers to absorb pumping forces

2. Capillaries connect arteries to veinsa) Exchange of gases and nutrients

3. Veins carry blood back toward hearta) Low pressureb) Large diameter minimizes resistance to flow.

LYMPH SYSTEM This system collects the fluid that leaks out

into the spaces between the cells and returns it to blood vessels.

This system is also involved in immune functions Foreign or defective cells (like bacteria, viruses,

and cancer cells) are removed in lymph nodes.

PLASMA AND CELLS: THE TWO MAJOR COMPONENTS OF BLOOD Blood Plasma is the liquid component of

blood Accounts for 60% of blood volume.1. Water makes 90% of the plasma2. Dissolved glucose, hormones, and urea (a waste

product of protein metabolism).3. Ions and salts such as Sodium, Potassium,

Chloride, and Bicarbonate.4. Proteins

a) Help keep water in the blood vesselsb) Helps transport some substancesc) Aids in blood clottingd) Antibodies eliminate foreign or defective cells.

PLASMA AND CELLS: THE TWO MAJOR COMPONENTS OF BLOOD Cells make up about 40% of the blood

volume.1. Red Blood Cells (erythrocytes) carry Oxygen on

hemoglobin (contain iron) molecules. a) Anemia: too few Red Blood Cells

2. White Blood Cells: also called leukocytes, aid in immune functions.

Lymphocytes, Monocytes, Neutrophils, Basophils, and Eosinophils

3. Platelets are fragments of megakaryocytes that are critical in blood clotting.

CIRCULATORY SYSTEM The human circulatory system is a two-loop

system1. Heart to lungs to heart (Pulmonary circulation)2. Heart to body to heart (Systemic circulation)

This system allows for maximum Oxygen delivery to the cells.

HEART The human heart is a 4-chambered heart

1. Atria/atrium: receive blood into the heart2. Ventricles: pump blood out of the heart3. Valves are present to allow only one-way flow

HEART Blood flow

1. From body via superior and inferior vena cava into the right atrium

2. Right atrium to Right ventricle3. Right ventricle to lungs via

pulmonary arteries4. From lungs to left atrium via

pulmonary veins5. From left atrium to left ventricle6. From left ventricle to body via aorta

ELECTRICAL CONDUCTION SYSTEM The cardiac muscle is triggered to contract

rhythmically1. An impulse is generated in the sino-atrial node

(SA node)2. This impulse ripples over the two atria3. The impulse then travels across the ventricles

pumping the blood out of the heart.

MEASUREMENTS OF CARDIAC FUNCTION1. Blood Pressure:

1. Systole is when the ventricles pump2. Diastole is when the ventricles fill3. Pressure is usually reported as systolic/diastolic

1. “normal” is about 120/802. EKG/ECG monitors and measures the

electrical activity of the heart.3. Pulse is counted in several areas of the

body1. “normal” is about 72/minute

4. Ultrasound is used to take a moving image of the heart and blood as the heart beats.

BLOOD TYPES There are many factors in blood typing, but

there are only 2 that we are concerned with:1. ABO Blood Types: Surface proteins A or B (co-

dominant) may be present resulting in Blood Type A, or B, or AB. If neither is present, the Blood Type is O.

2. Rh factor: The protein is either present (+) or not (-).

This is the factor that can cause problems between mothers and their unborn children.

RESPIRATORY SYSTEM The respiratory system is responsible for the

exchange of gases between the body and the atmosphere.

The respiratory system consists of the lungs plus all the airways and alveoli Oral cavity/nasal cavity pharynx larynx

trachea bronchi bronchioles alveoli Alveoli are sacs of epithelium covered with

capillaries and are the site of all gas exchanges.

The millions of alveoli give a surface area > 40 times greater than your body surface area.

RESPIRATORY EPITHELIUM Most airways are lined by a ciliated

epithelium and have cells that produce a lot of mucus. The mucus traps bacteria and viruses and

airborne particles (smoke, dust, etc.) that would cause trouble in the alveoli.

The cilia move this mucus and trapped junk to the larynx where it is swallowed.

The bacteria and viruses (and some of the particles) are digested/destroyed in the stomach.

NEGATIVE PRESSURE BREATHING The lungs are inside a closed thoracic cavity

bounded by the ribs and the diaphragm. Lifting the ribs and contracting the diaphragm

makes the cavity larger and reducing the pressure inside it (creates a partial vacuum).

Air is “sucked” into the lungs to equalize this vacuum.

The respiratory rate is controlled mostly by the concentration of CO2, but O2 concentration, pain, and emotional factors also influence the rate.

TRANSPORT OF OXYGEN Oxygen (O2) is carried by molecules of

hemoglobin in Red Blood Cells. It moves by simple diffusion from areas of high concentration to areas of low concentration. In lungs, O2 concentration is high in the alveoli

and low in the blood … oxygen diffuses into the blood.

In the tissues O2 concentration is high in the blood and low in the cells … oxygen diffuses into the cells.

TRANSPORT OF CARBON DIOXIDE (CO2) Carbon dioxide (CO2) is carried:

Dissolved in the plasma as CO2, about 5% On hemoglobin molecules on RBC’s, about 30% As part of the bicarbonate ion (HCO3

-) which acts as a buffer to maintain pH balance, about 65%

RESPIRATORY DISEASES1. Pneumonia: Inflammation and disease of the lung

tissue. May be due to viruses, bacteria, or allergy.

2. Chronic Obstructive Pulmonary Diseases (COPD)1. Asthma: airways constrict and reduce airway

diameter. Usually and allergic/immune system problem

2. Emphysema: loss of elastic fibers in lungs makes it hard to get air out of lungs so the person must “squeeze” his/her chest to get the air out. Smoking is the most common reason for this disease.

3. Lung Cancer: abnormal cell reproduction. Very deadly even with treatment. Smoking is the most common cause of this disease.