Anatomy and Physiology Exam #2

tunica intima

tunica intima

• the innermost layer of blood vessels

• composed of epithelial cells

systolic blood pressure

• peak arterial pressure during ventricular systole

• top number of a blood pressure reading

baroreceptors

• sense changes in blood pressure

precapillary sphincter

• segments of smooth muscle that help direct blood flow into capillaries

hypotension

• low blood pressure

chemoreceptor

• sense organ that responds to chemical stimuli

ANP & BNP

• ANP: Atrial Natriuretic Peptide

  • released by cells in the right atrium in response to increased blood volume and stretching of atrial walls

  • main function is to promote vasodilation

• BNP: Brain Natriuretic Peptide

  • released by cells in the ventricles in response to increased ventricular wall stress an pressure overload

  • promotes vasodilation

venule

• a very small vein

• collects blood from the capillaries

arteriole

• a very small blood vessel

• branches off of the arteries

• carry blood away from the heart to tissues and organs

muscular artery (+example)

• play a crucial role in regulating blood flow to specific tissues and organs

• adjust their diameter in response to various stimuli

• example: femoral artery

vasodilator (+example)

• causes a blood vessel to widen

• leads to increased blood flow

• example: histamine

elastic artery (+example)

• large arteries

• bring blood away from the heart to various organs and tissues

• elastic

• example: the aorta

medium vein (+example)

• size lies between small venules and large veins

• collect blood from smaller veins and bring it back to the heart

• example: brachial vein

large vein (+example)

• carry blood directly back into the heart

• large lumens

• example: superior vena cava

explain how the nervous system senses and responds to adjusts to disturbances in blood pressure

the nervous system sense disturbances in blood pressure through baroreceptors and respond by adjusting heart rate, and hormone secretion to maintain blood pressure

explain how capillary hydrostatic pressure and blood colloid osmotic pressure contribute to gas exchange

capillary hydrostatic pressure and blood colloid osmotic pressure create a dynamic balance that regulate fluid movement and facilitate gas exchange across capillary walls

explain how the precapillary sphincter regulates blood flow through a local capillary bed

the sphincter can open and close the entrance of the capillary, by which contraction causes blood flow in a capillary to change as vasomotion occurs

explain how veins are able to return blood to the heart under low pressure

the one way valves allow veins to efficiently return blood back to the heart under low pressure conditions, ensuring proper circulation and oxygenation

explain how the kidneys can increase blood pressure

the kidneys sense that the body needs more blood and oxygen, so it produces hormones that increase blood pressure

explain the relationship between blood flow, pressure, and resistance

if blood pressure increases, blood flow increases; if resistance increases blood flow decreases

the 3 layers of a blood vessel wall

1. tunica externa

2. tunica media

3. tunica intima

factors that determine resistance

• diameter of vessel

• vessel length

• turbulence of blood flow

• blood pressure

veins vs. arteries vs. capillaries

• veins:

  • carry blood back to the heart

  • thinner walls compared to arteries

  • smooth muscle

  • large lumens

  • example: superior and inferior vena cava

• arteries:

  • carry blood away from the heart

  • thicker walls

  • thick tunica media

  • example: aorta

• capillaries:

  • smallest vessels

  • most numerous

  • exchange gases, nutrients and waste products

  • thin, single layer walls

  • work through a network called capillary beds

continuous vs. sinusoidal capillaries

• continuous:

  • most common

  • connected by tight junctions

  • no gaps between cells

• sinusoidal:

  • large gaps between cells

lymphedema

• swelling in arms or legs

• caused by a lymphatic blockage

thoracic duct

• drains most of the lymph from body

• drains into the left subclavian vein

right lymphatic duct

• drains into the right subclavian vein

tonsilitis

• inflammation of the tonsils

peyer’s patches

• a group of lymphoid follicles

• line small intestine

• prevent infections

dendritic cell

• type of immune cell

• found in tissues

• boosts immune responses

• showing antigens on its surface to other cells of the immune system

mucous membrane

• moist, inner lining of organs and body cavities

interferons

• chemical messengers

• coordinate the defenses against viral infections

complement

• system of plasma proteins

• interact with pathogens to mark them for destruction of phagocytes

• in early phases of infection

neutralization

• stopping entry into host cells

opsonization

• increased activity of phagocytes

interleukins

• one group of related proteins

• made by leukocytes and other cells in the body

autoimmune disorder

• condition where the body’s immune system mistakes its own healthy tissues as foreign and attacks them

MALT (+example)

• Mucosa - Associated Lymphoid Tissue

• lymphoid tissues associated with mucosal membranes

• respiratory, digestive, and respiratory tracts

  • peyer’s patches

  • appendix

  • tonsils

cytokine (+example)

• small proteins

• secreted by various cells of the immune system

• play a key role in cell signaling, immune responses and inflammation

• example: interleukins and interferons

explain where lymph comes from

lymph originates from interstitial fluid that is collected by lymphatic capillaries and transported through lymphatic vessels back to the bloodstream

explain how lymph nodes filter the lymph

lymph nodes filter lymph by trapping and removing pathogen, foreign particles and debris that is present in the lymphex

explain the function of the tonsils

tonsils fight infections and help kill germs

explain where lymphocytopoiesis occurs

lymphocytopoiesis occurs in bone marrow, the thymus and the peripheral lymphoid tissue

explain how mast cells mediate inflammation

mast cells release various inflammatory mediators upon activation.

4 functions of lymphatic system

1. immune defense

2. fluid balance and circulation

3. absorption of dietary lipids

4. transport immune cells and antigens

2 functions of the spleen

1. immune function

2. blood filtration and storage

3 signs of inflammation

1. redness (erythema)

2. swelling (edema)

3. heat (increased temperature)

innate vs. adaptive immunity

• innate:

  • block or attack any foreign substance or pathogen

  • cannot distinguish one pathogen from another

  • born with

  • nonspecific

• adaptive:

  • specific

  • respond to specific pathogens

  • protects against future attack from same pathogen

  • ability to develop immunological memory

  • built over time

  • B-cells and T-cells

B cells vs. T cells

• B-cells:

  • make proteins (antibodies)

  • fight pathogens

• T-cells:

  • protect you by destroying harmful pathogens

  • send signals that help control your immune system’s response to threats

naturally acquired active immunity vs. artificially acquired active immunity

• naturally acquired active immunity:

  • when individual is exposed to pathogen

  • exposure can occur during infection

  • example: flu season

• artificially acquired active immunity:

  • vaccinations

  • the immune system will then recognize the antigen present in the vaccine

naturally acquired passive immunity vs. artificially acquired passive immunity

• naturally acquired passive immunity:

  • when antibodies transfer from mother to baby

  • these antibodies help protect the infant from infection

  • temporary

• artificially acquired passive immunity:

  • when antibodies are transferred from one individual to another through medical intervention

  • short-term protection

  • example: donor and recipient

respiratory mucosa

• mucous membrane lining the respiratory tract

• epithelium: barrier, secretion, absorption

cilia

• hairlike structure

• move mucus up

nasal conchae

• bony plates located on the lateral wall of the nasal cavity

• increase surface area of these cavities

meatus

• narrow passageways through conchae in the nasal cavity

• produce air turbulence

• slows down air movement

laryngitis

• inflammation of the larynx

hilum

• where pulmonary vessels, nerves and lymphatics enter lung

• groove in lungs

pleura

• a thin layer of tissue that covers the lungs and lines the interior wall of the chest cavity

• protects and cushions the lungs

surfactant

• oily fluid lubricates alveoli

• inadequate surfactant leads to respiratory distress syndrome

hypoxia

• low levels of oxygen to tissues

elastic rebound

• muscles of inhalation relax

• diaphragm and rib cage return to original positions

forceful breathing

• required muscle contractions during inspiration and expiration

• use of accessory muscles

intrapulmonary pressure

• the force exerted by gases within the alveoli

carbonic acid

• maintains the acid-base balance of the body

tidal volume

• the amount of air that moves in or out of the lungs with each respiratory cycle

respiratory rate

• the rate at which breathing occurs

• number of breaths taken in one minute

inspiratory capacity

• volume of air inhaled after a normal exhale

primary respiratory muscles involved in inhalation

• muscles that are responsible for expanding the thoracic cavity to allow air to enter the lungs

• example: diaphragm

sinus (+example)

• air spaces within the bones surrounding the nose

• example: frontal sinus

explain how food is prevented from entering the trachea

the epiglottis is a flap of cartilage that seals off the trachea when eating to prevent food from entering the trachea

explain how the autonomic nervous system regulated airflow through the respiratory system

• the sympathetic nervous system promotes bronchodilation

• the parasympathetic nervous system promotes bronchoconstriction

• these opposing actions help maintain airflow and ensure efficient gas exchange in the lungs

explain how gases are exchanged at the blood air barrier

• the blood air barrier provides an efficient interface for gas exchange between the respiratory system and the circulatory system

• oxygen is delivered to tissues and carbon dioxide is removed from the body

explain how structures within the nasal cavity condition the inhaled air

the conchae swirl the air around to allow the air time to humidify, warm and be cleaned before it enters the lungs

explain Boyle’s law to describe the relationship between pressure and volume

• as volumes increases, pressure decreases

• as pressure increases, volume decreases

explain what major factor prevents the lungs from collapsing

the surfactant prevents the collapse of the lungs by reducing surface tension. this allows for the maintenance of proper lung function and ensures efficient gas exchange during breathing

explain how increasing oxygen concentrations affect Hb saturation

when oxygen concentration increases, it leads to an increase in the saturation of hemoglobin with oxygen

explain how rising temperature affects Hb saturation

The raise in temperature will decrease the hemoglobin saturation

explain how pressure changes in the thoracic cavity during the respiratory cycle

• inhalation: the pressure inside the lungs decreases as air rushes in

• exhalation: the increase of pressure within the thoracic cavity forces air out of the lungs

list sinuses

1. frontal sinuses

2. maxillary sinuses

3. ethmoid sinuses

4. sphenoid sinuses

4 respiratory defenses

1. mucociliary clearance

2. cough reflex

3. immunological defenses

4. reflexive bronchoconstriction

left versus right lung anatomy

• right lung:

  • three lobes

  • shorter than left due to the liver

• left lung:

  • two lobes due to the heart

  • longer than right

external versus internal respiration

• internal respiration:

  • occurs in body tissues

  • cells release carbon dioxide and take in oxygen from the blood

• external respiration:

  • occurs in the lungs

  • occurs when the body takes in oxygen from the atmosphere and releases carbon dioxide