Bio Lab II Respiratory/Cardiovascular Body Systems

Closed circulatory system

network of blood vessels (arteries, veins, capillaries) where blood is confined, enabling high-pressure, efficient transport of oxygen and nutrients to tissues

Main function of the Cardiovascular system

to deliver oxygen and nutrients and to remove carbon dioxide and other waste products

Blood Vessel Layers

1. Tunic intima (inner lining)

2. Tunic media (middle muscle layer)

3. Tunic externa (outer supportive layer)

Tunica Intima

provides a smooth, frictionless surface for blood flow and acts as a barrier that prevents clotting and regulates vessel diameter; endothelium

Tunic Media

thickest layer, containing smooth muscle cells and elastic fibers; controlled by sympathetic nervous system

Tunic Externa

outermost layer composed of connective tissue, primarily collagen fibers, which anchors the vessels to surrounding tissues and provides structural support

Arteries

muscular, elastic blood vessels that transport blood away from the heart, typically carrying oxygen-rich blood to tissues and organs

Arterioles

small-diameter blood vessels in the microcirculation that branch off from arteries and lead into capillaries

Capillaries

the smallest and most numerous blood vessels in the human body, acting as the crucial link between the arterial and venous systems

Venules

small, thin-walled blood vessels that collect deoxygenated blood from capillaries and transport it toward larger veins

Veins

blood vessels in the cardiovascular system that carry blood toward the heart

Lumens

the inner, open space or cavity within a tubular structure, organ, or cell organelle

Lumens of arteries vs veins

Arteries have a narrow, small lumen designed to maintain high blood pressure, while veins have a large, wide lumen to accommodate high-volume, low-pressure blood flow

arteries < veins

Arterial blood

the bright red, highly oxygenated blood transported by arteries from the heart to tissues, representing the oxygenated side of the circulatory system

Blood

specialized circulating connective tissue composed of cells suspended in plasma, responsible for transporting oxygen, nutrients, and waste throughout the body

Heart

fist-sized, muscular organ that serves as the primary pump in the cardiovascular system, continuously circulating blood throughout the body to deliver oxygen and nutrients while removing waste

Myocardium

the thick, middle muscular layer of the heart wall, responsible for the involuntary contraction and relaxation that pumps blood throughout the body

Heart Anatomy

Coronary arteries

the blood vessels that branch from the aorta to supply oxygen-rich blood and nutrients specifically to the heart muscle (myocardium)

Cardiac veins

specialized blood vessels that remove deoxygenated blood and metabolic waste from the myocardium (heart muscle), returning it to the right atrium

Coronary sinus

the largest vein of the heart, located on its posterior aspect between the left atrium and ventricle

The 4 heart chambers

1. Right Atrium — receives deoxygenated blood from the body

2. Right Ventricle — pumps deoxygenated blood to the lungs for oxygen

3. Left Atrium — receives oxygen-rich blood back from the lungs

4. Left Ventricle — pumps oxygen-rich blood to the rest of the body

Pathway of Blood

1. Venae cavae

2. Right atrium

3. Tricuspid valve

4. Right ventricle

5. Pulmonary semilunar valve

6. Pulmonary artery/Lungs

7. Pulmonary veins

8. Left atrium

9. Bicuspid valve

10. Left ventricle

11. Aortic valve

12. Aorta Body

Intrinsic conduction system

network of specialized, non-contractile cardiac cells that initiate and distribute electrical impulses, setting the heart's rhythm and coordinating contraction

Sinoatrial (SA) node

the heart's primary pacemaker, a specialized bundle of myocytes located in the right atrium near the superior vena cava

Atrioventricular (AV) node

a critical component of the heart's electrical conduction system, located in the right atrium near the interatrial septum

Atrioventricular bundle

a specialized group of cardiac muscle fibers responsible for conducting electrical impulses from the atrioventricular (AV) node to the ventricles

Bundle Branches

specialized cardiac muscle fibers that conduct electrical impulses from the bundle of His to the Purkinje fibers, causing the ventricles to contract and pump blood

Purkinje fibers

specialized, fast-conducting cardiac muscle cells located in the inner ventricular walls (subendocardium) of the heart

Systole (contraction/top number)

the heart muscle contracts, forcing blood out of the ventricles into the aorta and pulmonary artery

Diastole (relaxation/bottom number)

the heart muscle relaxes, allowing the ventricles to fill with blood from the atria

Pulse

the rhythmic, palpable expansion and contraction of an artery caused by the ejection of blood from the heart's left ventricle during each cardiac cycle

Brachial artery

the primary blood vessel supplying oxygen-rich blood to the upper arm

measurements by health professionals are made on the pressure in large arteries like this one

Sphygmomanometer

medical device used to measure blood pressure by temporarily restricting blood flow, composed of an inflatable cuff, inflation bulb, and manometer; measures systolic and diastolic pressure

Renin

hormonal control

Factors that effect blood pressure

1. Temperature

2. Chemicals

3. Diet

Variations in Blood Pressure

1. normal

2. hypotension

3. hypertension

Normal blood pressure

140—110mm Hg systolic

80—75mm Hg diastolic

Hypotension

Low systolic (below 110mm Hg)

Often associated with illness

Hypertension

High systolic (above 140mm Hg)

Can be dangerous if it’s chronic

Lungs

the primary, paired sponge-like respiratory organs in air-breathing vertebrates, situated within the thoracic cavity

Alveoli

microscopic, balloon-like air sacs located at the end of the bronchioles in the lungs

Inspiration

the active physiological process of drawing air into the lungs, driven by the contraction of the diaphragm and external intercostal muscles

Expiration

the passive process of breathing out, where air containing carbon dioxide is expelled from the lungs

Spirometer

scientific instrument used in biology and medicine to measure the volume and speed of air inspired and expired by the lungs

Tidal volume (TV)

the normal amount of air that moves into and out of lungs with normal breath

Inspiratory reserve volume (IRV)

the amount of air that can be forcibly inhaled after a normal breath

Expiratory reserve volume (ERV)

the amount of air that can be forcibly exhaled after a normal breath

Vital capacity (VC)

the volume of air that can be forcibly exhaled after forcibly inhaling