Anatomy Exam 3: Cardiovascular System ( part 3)

cardiovascular system

• blood

• blood vessels

• heart

blood

transports materials throughout the body

• plasma

• erythrocytes

• leukocytes

• thrombocytes

plasma

• apart of blood

  • water

  • small solutes

  • proteins

erythrocytes

• apart of blood

• transports oxygen

• hemoglobin

• limited lifespan; regularly replaced

mammals (erythrocytes)

• biconcave disks

• no nucleus or organelles

leukocytes

defense functions

thrombocytes (platelets)

• blood clotting

• vessel repair

blood vessels

• passages for blood

• moves along pressure gradient

• veins

• capillaries

• arteries

• arterioles

• venules

heart pressurizes blood…

sends pulses of blood into vessels

blood pressure decreases as…

blood moves through small vessels

arteries

• carry blood away from heart

• high pressure

• fluctuations in blood pressure

• high elasticity

• thick smooth muscle layer

• thick connective tissue layer

arterioles

• small artery leading to capillaries

• low pressure

• inelastic

• small diameter

• connect arteries to capillaries

• thin smooth muscle layer

• constrict and dilate to  regulate arterial blood pressure

blood vessels layers

• tunica interna

  • endothelium

  • basement membrane

  • elastic fibers

• tunica media

• tunica externa

• vasa vasorum

• nervi vasorum

tunica interna

• inner layer

  • endothelium

  • basement membrane

  • elastic fibers

endothelium

• apart of tunica interna

• flattened epithelial cells

basement membrane (blood vessels)

• apart of tunica interna

• collagen fibers

elastic fibers

• apart of tunica interna

• prominent in arteries

tunica media

• blood vessel middle layer

• smooth muscle

tunica externa

• bloodvessel outer layer

• connective tissue

• elastic fibers

vasa vasorum

• blood vessels delivering blood to large vessels

nervi vasorum

nerves innervating blood vessels

capillaries

• exchange between blood and body

• filtration

• reabsorption

• slower blood flow

filtration

• capillaries

• at arterial end

• materials leave capillaries

reabsorption

• capillaries

• at venous end

• materials enter capillaries

endothelium (capillaries)

• single layer flattened epithelial cells

pericytes

• capillaries

• regulatory cells

large number of capillaries…

increases the size

precapillary sphincters

• regulate flow through capillaries

  • not enough blood in body to fill all capillaries

metarterioles

• allow blood to bypass capillaries

continuous capillaries

• form continuous tube

• tight junctions

• ex) brain

fenestrated capillaries

• pores in endothelial cell membranes

• ex) kidneys, small intenstine

Sinusoids

• gaps between endothelial cell and in basement membrane

• ex) liver, spleen

veins

• apart of blood vessels

• carry blood toward heart

• low pressure

• may have one way valves

• respiratory pump

one-way valves

prevent backflow

skeletal muscle pump

muscle contraction moves blood toward heart

respiratory pump

inspiration draws blood toward the heart

lymphatic system

associated with the circulatory system that picks up the extra fluid that doesn’t get reabsorbed and carries it through the vessels back to the big veins near the heart

lymphatic vessels

• returns fluid and proteins to system

• transport fat from digestive to circulatory system

lymphatic structures

• defense; lymphocytes and macrophages

• lymph nodes tonsils, appendix, spleen, Peyer’s patches, thymus, bone marrow

lymphatic vessels

• lympgh pass through lymph nodes: filtration

• one-way flo; one-way valves prevent backflow

lymph moved by (lymphatic vessels

• contraction of vessel walls (myoepithelial cells)

• skeletal muscle pumps; respiratory pump

• myoepithelial cells 

  • act like muscle cells

hepatic portal system

• set of vessels that carry blood from one set of capillaries to another set of capillaries

• carries blood between capillary beds

  • digestive tract

  • pancreas

  • spleen

    • carries to liver then return back to heart 

digestive tract (hepatic portal system)

• within the hepatic portal system

• picks up glucose, amino acids, toxins

pancreas (hepatic portal system)

• within hepatic portal system

• picks up insulin and glucagon

spleen (hepatic portal system)

• within hepatic portal system

• bilirubin (breakdown of hemoglobin)

cardiac cycle (heart)

• contracts and pumps blood

• left and right sides of ___ contract at same time

• systole

• diastole

ventricles

atria contract to fill ___ to capacity, then ___ contract

systole

• contraction of heart

• pulse of blood enters arteries —» pressure increases

• blood out

diastole

• relaxation of heart

• pulse passes through arteries —» pressure decreases

• blood in, chambers expand

layers of heart

• epicardium

• myocardium

• endocaridum

• pericardium

epicardium

• layer of heart

• outer serosal membrane

  • produces fluid

myocardium

• layer of heart

• middle layer

• muscle layer

endocardium

• heart layer

• epithelial tissue; continuous with endothelium of vessels

pericardium

• fluid filled sac within which heart is located

double loop circuit

• blood flow of heart

  • pulmonary loop

  • systemic loop

systemic loop

heart —» head and body —» heart

pulmonary loop

heart —» lungs —» heart

Pulmonary Arteries

• high pressure

• low oxygen (picks up oxygen at lungs)

• heart to lungs

Pulmonary Veins

• low pressure

• high oxygen

• lungs to heart

systemic arteries

• high pressure

• high oxygen

• heart to head and body

systemic veins

• low pressure

• low oxygen'

• head and body to heart

coordination of heart contractions

electrical conducting system

• sinoartrial node

• fibrous skeleton

• artioventricular node

• bundle of His, Purkinje fibers

• ventricle contraction

sinoatrial node

• in right atrium

• initiates electrical signals

• paces contraction

• pacemaker of the heart

fibrous skeleton

• prevents electrical signals from spreading to ventricles

atrioventricular node

• conveys signals to ventricles after delay

Bundle of His, Purkinje fibers

• deliver signals to ventricles

Ventricular Contraction

• apex to base

fetal circulation (before birth)

• getting oxygen and nutrients from placenta

• need to send blood to placenta

• don’t need to send much blood to lungs

fetal circulation (after birth)

• ductus venosus

• ductus arteriosus

• foramen ovale

ductus venosus becomes…

ligamentum venosum

ductus arteriosus becomes…

ligamentum arteriosum

foramen ovale closes, becomes…

fossa ovalis

hepatic portal vein

carries blood from umbilical vein to liver

ductus venosus

carries blood from umbilical vein to inferior vena vaca

foramen ovale

directs blood from right atrium to left atrium

ductus arteriosus

directs blood from pulmonary trunk to aorta