Human Physiology II - Vocab (For Final)

Ant-Diuretic Hormone

Hormone that allows reabsorption back into the blood

Oxytocin

Hormone that causes uterine contraction and milk release

Tropic Hormones

A hormone that triggers the release of another hormone

Luteinizing hormone

Hormone the synthesis and secrete estrogen and progesterone, follicle maturation, and ovulation

Follicle-stimulating hormone

synthesis, preparation, and secretion of testosterone

Thyroid Gland

Located in the anterior neck, superficial to the trachea

Parathyroid Gland

Within the posterior surface of the thyroid

Fibrous Pericardium

Outer layer of connective tissue; it is tough and fused to the diaphragm

Serous pericardium

Inner membrane that folds 2 layers

Layers of the pericardium

* parietal layer
* visceral layer (epicardium)
* pericardial layer

Parietal Layer

Fused to the inner surface of the fibrous pericardium (Outer layer)

Visceral Layer (Epicardium)

Inner layer closest to the heart wall

Pericardial Layer

Between the parietal & visceral layer, filled with serous fluid (pericardial fluid)

Layers of the Heart Wall

* Visceral Pericardium
* Myocardium
* Endocardium

Visceral Pericardium (Epicardium)

Includes a thin layer of connective tissue containing fat tissue

Myocardium

The main component that makes up the wall of the heart; mostly cardiac muscle cell (myocytes) also contains specialized pacemaker cells and connective

Endocardium

Innermost layer of the heart wall, faces the lumen of the heart chambers; simple squamous epithelium (endothelium) and layers of connective tissue containing collagen and fibers

Interventricular Septum

Separates right and left side of heart

Heart Valves

* Atrioventricular (AV)
* Tricuspid
* Bicuspid (Mitral)
* Semilunar
* Pulmonary
* Aortic

Atrioventricular (AV) Valves

Between the atria and ventricles

Tricuspid Valves

Between the right atrium and right ventricle; contains 3 cusps

Bicuspid (Mitral) Valves

Between the left atrium and left ventricle

Semilunar Valves

Between the ventricles and the pulmonary artery and aorta

Pulmonary Valves

Between right ventricle and pulmonary trunk

Aortic

Between left ventricle and aorta

Myocytes

99% of cells; striated muscle fibers; generate action potential when membrane is depolarized to threshold; the source of force - production of the heart muscle

Pacemaker Cells

1% of cells; generate spontaneous, rhythmic action potentials (signal for myocyte contraction); cells do not contribute to the contractile force of the heart

Intercalated Discs

Join myocytes together & connect pacemaker cells to contractile cells

Desmosomes

Hold cells together

Gap Junctions

Allow ions to pass rapidly from one cell to another

Systole

One period of contraction in Cardiac Cycle for each chamber of the heart

Diastole

One period of relaxation in the Cardiac Cycle for each chamber of the heart

End-Diastolic Volume

The total amount of blood in the ventricle at the end of ventricular diastole

Isometric

When the pressure in the ventricles is not yet high enough to push open the semilunar valves

Heart Rate

The number of cardiac cycles or ‘beats’ per minute (BPM)

Stroke Volume

The volume of blood pumped out of the left ventricle in one heart beat (Units: mL)

Cardiac Output

The volume of blood pumped out of the left ventricle in 1 minute (Units: L/min)

Venous Return

The volume of blood in the ventricle coming back into the heart in 1 minute (at rest VR = CO)

Preload

The amount of stretch of the sarcomeres in ventricular myocytes before the contract

* mainly determined by EDV
* relationship between stretch and force

Contractility

The heart’s intrinsic ability to contract (generate force to pump)

Afterload

The force that the ventricles must overcome in order to eject blood into their arteries overcome

Inotropic Agents

Agents that affect contractility

Tunica Intima

The innermost lining of the veins and arteries /endothelial cells (simple squamous epithelia) & layer of connective tissue and elastic laminae

Tunica Media

Middle layer consists of smooth muscle & elastic laminae

Tunica Externa

Outer layer of dense irregular collagenous connective tissue

Blood pressure

Outward force that the blood exerts on the walls of blood vessel

Systolic pressure

The pressure of blood against the artery walls during systole

diastolic pressure

The pressure of the blood against the artery walls during diastole

Peripheral Resistance

Caused by anything that hinders blood flow through the vascular periphery

* as peripheral resistance increases; blood pressure increases

Ventricular Filling Phase

* Step 1 of the Cardiac Cycle
* Ventricles fill with blood and are in diastole
* Atrioventricular (tricuspid and mitral) valvews are open
* Atrial systole occurs
* Semilunar valves are closed

Isovolumetric Contraction Phase

* Step 2 of the Cardiac Cycle
* Ventricular systole begins
* AV and semilunar (aortic and pulmonary) valves close when enough pressure builds in the ventricles
* Atrial diastole begins

Ventricular Ejection Phase

* Step 3 of the Cardiac Cycle
* Ventricular systole continues
* AV valves are still closed
* Atrial diastole continues
* Pressure opens SL valves, and blood is ejected into the pulmonary artery and aorta

Isovolumetric Relaxation

* Step 4 of the Cardiac Cycle
* Ventricular diastole begins
* AV valves are still closed
* Atrial diastole continues
* SL valves close

Blood pressure

Outward force that the blood exerts on the walls of blood vessels (Units: mmHg)

Peripheral Resistance

Caused by anything that hinders blood flow through the vasculature periphery

Skeletal Muscle Pumps

The skeletal muscles surrounding the deeper veins of the limbs squeeze blood in the veins to help propel it toward the heart

Upper Respiratory Tract

Airways from the nasal cavity to the larynx

Lower Respiratory Tract

Airways from trachea → lungs (Bronchi → bronchioles → alveoli)

Nasal Cavity

Inside of the nose

3 sections of the Pharynx (Throat)

* nasopharynx
* Oropharynx
* Laryngopharynx

Nasopharynx

Lined with pseudostratified columnar epithelium and important for warming, humidifying, and filtering inspired air

Oropharynx

Passageway for both air and food

Laryngopharynx

Also a common passageway for both air and food: anterior portion opens into larynx and posterior opens into esophagus

Larynx

AKA the voice box. Important passageway for keeping food and liquids out of the respiratory tract.

Glottis

Opening to the larynx

Epiglottis

Blocks the entryway into the larynx

Smooth Muscle lining

The small airways can change diameter to control air flow into specific bronchioles and alveoli

Type I Aveolar Cells

Form in the innermost layer of the respiratory membrane. O2 and CO2 diffuse across these cells

* Simple Squamous cells
* (0% of cells in the alveoli

Type II alveolar cells

* Small cuboidal cells
* Account for 10% of alveolar wall
* Responsible for making and secreting surfacant
* Alveolar Macrophages

Surfacant

A chemical that reduces the surface tension of inner alveolar wall

Parietal Pleura

Encases the lung

* Outer layer
* Fused to rib cage and diaphragm
* Turns over itself

Visceral Pleura

Encases each lung

* Inner layer
* Continuous with the surface of the lungs
* Divides into fissure to form the lobes

The 2 main pressures that determine air flow into and out of the lungs

Atmospheric pressure and Intrapulmonary Pressure

Atmospheric Pressure

Pressure of the air outside of the body (determined by sea level)

Intrapulmonary Pressure

Pressure within all the alveoli

Intrapleural Pressure

Pressure within the pleural cavity and it changes a small amount during pulmonary ventilation

Factors that influence Pulmonary Ventilation

* Airway resistance
* Alveolar Surface Tension
* Pulmonary Compliance

Airway Resistance

Anything that impedes airflow at any point along the respiratory tract. Largely determined by the airway diameter

Bronchodilation

Relaxation - increase the diamater of bronchioles; decreases airway resistance; and increases air flow

Bronchoconstriction

Contraction - Decreases the diameter of bronchioles; increases the airway resistance; and decreases airflow

Alveolar Surface Tension

The tension set up at the gas-water boundary

Pulmonary Compliance

The ease of the lungs and chest wall to stretch

3 factors that determine Pulmonary Compliance

* Degree of alveolar surface tension
* Distensibility of elastic tissue
* The ability of the chest wall to move or stretch during inspiration

Degree of alveolar Surface tension

Surfactant decreases surface tension so that the alveoli can inflate more easily

Distensibility of Elastic Tissue

Give lungs the ability to stretch during inflation

Tidal Volume

Amount of air inspired or expired during ventilation at rest

Inspiratory Reserve Volume

Amount of air that can be forcibly inspired after normal inspiration

Expiratory Reserve Volume

Amount of air that can be forcibly expired after normal expiration

Residual Volume

The air remaining in the lungs after max expiration

Inspiratory Capacity

Total amount of air that a person can inspire

Functional Residual Capacity

Amount of air left in the lungs after tidal expiration

Vital Capacity

Total amount of exchangeable air

Total lung capacity

Total amount of air that can fill the lungs

Hyperventilation

More CO2 expired

Respiratory Alkalosis

Too low of a pH

Hypoventilation

Less CO2 expired

Respiratory Acidosis

Too low of a pH

Eupnea

Normal breathing

Plasma

One of two major components of blood; liquid extracellular matrix of blood

Eythrocytes

Red Blood Cells