Module 4: Circulation, Exchange, and Reproduction

Tunica intima

flattened, smooth layer of cells called endothelial cells

Tunica media

smooth muscle or elastic fibers

Tunica adventitia

 fibrous connective tissue

Arteries

Thick-walled, elastic vessels carrying blood away from the heart. Most carry oxygen-rich blood 

Veins

Thin-walled, less elastic, carrying blood to the heart. Most carry oxygen-poor blood

Pulmonary artery

carries low O2 blood to the lungs

Pulmonary vein

carries blood high in oxygen

Capillaries

Tiny, one-cell-thick vessels where exchange happens (oxygen, nutrients, waste)

Systemic Circulation

delivers blood to all body cells and carries away waste

Pulmonary Circulation

eliminates carbon dioxide and oxygenates blood

Fibrous Pericardium

encloses the heart (like a bag) and is the tough, outermost layer of your pericardium; made of connective tissue that prevents your heart from expanding too much

Visceral pericardium

inner layer of the serous pericardium

Parietal pericardium

outer layer of the serous pericardium

Serous pericardium

This is the inner layer of your pericardium. It’s actually made of two layers. 

Pericardial cavity

contains fluid reducing friction

Epicardium

outer layer of the heart wall, protects the heart and reduces friction using a slippery, serous membrane

Myocardium

middle layer of the heart; thick, muscular layer responsible for pumping action

Endocardium

 inner layer of the heart; smooth surface minimizing resistance to blood flow

Lymph

 interstitial fluid (fills the spaces between cells in tissues) in the lymphatic system

Lymphatic vessels

transport lymph from the tissues to the bloodstream

Cells

immune system cells including phagocytic cells and, more importantly, lymphocytes 

Lymph nodes

act as filters for the body, removing harmful substances like bacteria and viruses

Thymus

produce and mature T-lymphocytes (T-cells), which are a type of white blood cell crucial for the immune system

Spleen

filters the blood, removes old blood cells, recycles iron,  makes antibodies

Cooley’s anemia

 an inherited disorder that interferes with the blood’s ability to carry oxygen

Cooley’s anemia symptoms

Swollen abdomen, enlarged spleen, tiredness, and weakness 

Cooley’s anemia relationship to blood

Blood has hypochromia, meaning that the red blood cells having less color than normal due to a reduced amount of hemoglobin, the oxygen-carrying pigment

Atrial septal defect

a hole in the atrial septum, which is the wall that separates your heart’s two upper chambers (atria)

Atrial septal defect symptoms

a heart murmur 

Atrial septal defect relationship to the heart

The hole increases the amount of blood going through the lung. It also causes oxygenated blood to mix with deoxygenated blood. 

Internal respiration

gas exchange between blood and deep body tissues

External respiration

gas exchange between the environment and blood

Inhalation/inspiration

breathing IN

Exhalation/expiration

breathing OUT

Ventilation

the movement of air into and out of the lungs

Surface area

Greater SA = greater efficiency of gas exchange

Distance

Shorter distance = greater efficiency of gas exchange

Resistance

Moist surfaces = less resistance = greater efficiency of gas exchange

Nasal cavity

The hollow space inside the nose that serves as the entrance to the respiratory system 

Pharynx

a passageway for both air and food and connects the nasal and oral cavities to the larynx and esophagus

3 Sections of Pharynx

Nasopharynx, Oropharynx, Laryngopharynx

Larynx

enlargement at the top of the trachea, houses vocal cords

Epiglottis

flap that closes when you swallow, preventing food from going into the airway 

Trachea

cylinder with stiff cartilage to keep it from collapsing - leads to the BRONCHIAL TREE

Bronchi

 are larger airways supported by cartilage, which keeps them open, and they branch off from the trachea into the right and left lungs

Bronchioles

are smaller, thinner airways that lack cartilage and lead to the alveoli, where gas exchange occurs

Lungs

spongy tissue that sit within the pleural cavity

Right lungs

3 Lobes

Left lungs

2 Lobes

Cardiac Notch

space for the heart

Serous fluid

lubricates lungs during breathing

List, in order, the respiratory structures that air passes through during inhalation

nose, pharynx, larynx, trachea, bronchi, bronchioles, alveoli

List, in order, the respiratory structures that air passes through during exhalation

Diaphragm, Alveoli, Lungs and Bronchi, Trachea, Larynx, Pharynx, and nose

Ventricular septal defect

a hole between the 2 bottom pumping chambers of the heart (ventricles)

Ventricular hypertrophy

Walls of the right ventricle get thicker due to the right part of the heart has to work harder

Pulmonary stenosis

The pulmonary valve is more narrow than normal making it harder for the right ventricle to pump blood to the lungs  

Enlarged aortic valve

Aorta is shifted to the right and sits directly above the hole in the heart wall

Vivien Thomas

developed a method of arterial shunting that helped to save the lives of thousands of children with congenital "blue baby"  heart defects, including tetralogy of Fallot

Cystic fibrosis

 a genetic, progressive disease that causes sticky mucus to build up primarily in the lungs, but also in the digestive tract and sinuses 

Cystic fibrosis symptoms

low energy, frequent lung infections, trouble breathing, inability to gain weight 

Cystic fibrosis causes

Caused by a mutation to the CFTR gene. Mutated CFTR channels are broken causing chlorine to build up which attracts water (osmosis!). This causes a thick mucus to build up extracellular space, restricting air flow

What direction does air move in?

Air moves from high pressure → low pressure.

The effects of injury to the thoracic cavity on ventilation

Intrapleural pressure equal to or possibly greater than intrapulmonary pressure, and subsequent lung collapse.