ya i slept out, then u crept out, ur in the west now, now im stressed out, im on the east side, im w my gs like, u know she cheating, ur on some weak ting, should be a g ting gyalis on a free ting champs and a weed ting enemies leaking,

uncle on the ital diet like marley moving like a rasta in the markey garvey

diffusion is rapid only over small distances

two solutions to this?

thin surfaces decrease diffusion distance

circulatory system to move substances

Cnidarians, which include the hydras and jellyfish, do not have a distinct circulatory system. How have they solved the problem of exchange?

Thin body wall allow oxy to diffuse in and co2 out easily

gastrovascular cavity extends through body, nutrient are close to cells

Flatworms (phylum Platyhelminthes) such as planaria have a slightly different solution to this diffusion problem. What is it?

dorsoventrally flattened body allows nutrient from outside to diffuse in easily

Why do large animals need a circulatory system instead of relying on diffusion alone?

cells are too far from outside environment=diffusion slow over long distances

What is the main function of the circulatory system in animals?

move nutrients quickly between exchange organs

Contrast open circulatory systems with closed circulatory systems.

open=fluid is hemolymph, pumped by heart into body spaces that directly surround organ

closed=fluid is blood, contained in vessels, exchange through capillary walls

closed circulatory system benefit

higher bp (efficiency)

Identify and Define

Aorta, largest artery in the body carrying oxy-rich blood from left ventricle to body

Identify and Define

pulmonary artery, artery carrying oxy-poor blood from right ventricle to lung

identify and define

left lung, receives oxy poor blood from pulmonary artery, allows gas exchange, sends oxy rich blood back to heart through pulmonary vein

identify and define

right lung, receives oxy poor blood from pulmonary artery, allows gas exchange, sends oxy rich blood back to heart through pulmonary vein

identify and define

left atrium, upper chamber of heart receiving oxy rich blood from lungs through pulmonary veins

identify and define

left ventricle, lower chamber of heart pumping oxy rich blood into aorta (strongest chamber)

identify and define

inferior vena cava, vein pumping oxy poor blood from lower body to right atrium

identify and define

superior vena cava, vein pumping oxy poor blood from upper body to right atrium

which vena cava functions in bringing oxy poor blood from lower body to right atrium

inferior

what is systemic circulation +pathway

pathway between heart and body tissues

left ventricle aorta body capillaries vena cava right atrium

what is pulmonary circulation + pathway

pathway between heart and lungs

right ventricle pulmonary arteries lung capillaries pulmonary vein left atrium

#1

right ventricle containing oxy poor blood is pumped outward to lungs

#2

pulmonary artery carrying oxy poor away from heart to lung

#3

gas exchange, Blood enters oxy poor leave oxy rich as co2 out blood o2 in blood

#4

Freshly oxygenated blood from the lungs enters the left atrium.

#5

left ventricle carrying oxy rich to whole body

#6

Oxygenated blood leaves the heart and gets distributed to body tissues through aorta

#7

systemic capillaries delivers o2 and nutrients to upper body cells while taking in co2 and waste

#8

systemic capillaries deliver o2 and nutrients to lower body cells while taking in co2 and waste

the status of #7 and #8 blood goes from ___ to ____

oxy rich to oxy poor

#9

superior vena cava carries oxy poor blood from upper body into right atrium

#10

inferior vena cava carries oxy poor blood from lower body into right atrium

#11

oxy poor blood enters right atrium then moves into right ventricle

What are the four chambers of the heart

right atrium

right ventricle

left atrium

left ventricle

What is the function of the atria? + left and right

receive blood returning to heart

right takes oxy poor from body

left takes oxy rich from lung

What is the function of the ventricles? + left and right

ventricle pump blood out heart

right pumps oxy poor blood to lungs

left pumps oxy rich to body

Which side of the heart sends blood to the lungs?

right

Which chamber pumps blood to the body?

left ventricle

Which vessel carries oxygen-poor blood to the lungs?

pulmonary artery

Which vessel carries oxygen-rich blood to the body?

aorta

what dis

fish

two chambered heart with single circulation

blood flows from heart gills body heart

top is gills, oxy poor area where exchange makes oxy rich

bottom is body

what dis

amphibian

3 chambered heart with double circulation

-pulmocutaneous circuit goes heart lung/skin heart (exchange by lung/skin)

-systemic heart body heart

what dis

reptile

3 chambered heart (crocs have 4)

double circulation

-pulmonary circuit

-systemic circuit

what is the difference between mammal and reptile in this picture

reptile has 3 chambers with 1 ventricle partially divided

Why is a four-chambered heart a key adaptation required for endothermy?

keeps oxy rich and poor separate, allowing delivery of oxy rich to tissue at high pressure

Explain why the four-chambered hearts of birds and mammals are considered an example of

convergent evolution

both groups needed to separate oxy rich and oxy poor to support high metabolic rates

cardiac cycle meaning

one complete heartbeat where heart fills with blood, then pumps blood out

systole explained

contraction phase where heart squeezes and pumps blood out

diastole explained

relaxation phase where heart relaxes and the chambers fill with blood

cardiac output explained

amount of blood the heart pumps per minute

(hr * stroke volume)

heart electrical system explained

specialized cell in wall of right atrium called sa node sets heart rhythms through electrical signals

what this (no func needed)

sa node

what this (no func needed)

av node

What is the function of the sinoatrial (SA) node?

create electrical signal that causes atria to contract and pus blood intro ventricles

Why is the SA node called the pacemaker of the heart?

sets rhythm of heartbeat

What is the function of the atrioventricular (AV) node

delay signal from sa node to allow blood movement from atria to ventricle

send contraction signal to ventricle

Why is there a delay at the AV node important?

ensures ventricles have enough time to fill with blood before contractions

Electrical impulses from the SA node cause the atria to contract and are conducted to a relay

station, the atrioventricular (AV) node. When an impulse is generated by the AV node, what contracts?

ventricles

What does the P wave represent in an ECG?

atrial depolarization

What happens in the heart during the QRS complex?

ventricular depolarization, electrical signal spreads through ventricles causing contraction

What happens during the T wave?

ventricular repolarization, reset of ventricles causing relaxation

Which part of the ECG shows ventricular contraction?

qrs complex, shows electrical signal that causes ventricular contraction

What is the main function of arteries? + 1 exception

carry blood away from heart mainly oxy rich

pulmonary artery is an exception that carries oxy poor from right ventricle to lung

What is the main function of veins? + 1 exception

carry blood back to heart, mainly oxy poor

pulmonary vein carry oxy rich from lung to left atrium

Why do veins have valves?

prevent backflow ensuring one direction

What is the function of capillaries?

exchange of oxy nutrients co2 and waste

Which blood vessels have the thinnest walls

capillaries

What factors help blood flow in veins against gravity?

valves

skeletal muscle contraction

breathing

How do skeletal muscles help blood return to the heart

squeeze veins, pushing blood back to heart

What is the role of blood pressure in arteries vs veins?

arteries high bp to receive blood directly from heart and push to body

vein low bp as already passed through capillaries,

What are precapillary sphincters

tiny rings of smooth muscle at entrance of capillary beds controlling whether blood flow into capillary bed or bypasses

what are capillary beds

network of tiny capillaries where exchange happens between blood and tissue

how do precapillary sphincters control blood flow?

when relax = more blood into capillary bed

when contract = less

what type of muscle and precapillary sphincters

smooth

What type of vessel is responsible for exchange between blood and tissues?

capillaries

What is plasma?

liquid solution of blood carrying

blood cell

nutrient

hormone

waste

protein

two parts of plasma

liquid

formed element

What percentage of blood is made of cells?

45 cells

55 plasma

What are the main components of blood?

plasma

rbc

wbc

platelets

what platelets and function

cell fragments that help blood clot

neutrophils are ___ that function in

wbc, first reponse to bacteria

lymphocytes are ___ that function in

wbc, immune memory / antibody

monocytes are ___ that function in

wbc, macrophage

eosinophile are ___ that function in

wbc, fight parasites

basophils are ___ that function in

wbc, release histamine

Blood separates into two components, a liquid matrix called ______________________ and the cellular

elements

plasma

four major constitutents of plasma + funcs

water-regulate temp

ions-maintain ph

plasma protein-maintain blood osmo pressure

transported substance-nutrients

Describe three ways in which the structure of an erythrocyte enhances its function, which is to transport

oxygen.

biconcave - increase surface area for oxy diffuse

no nucleus - more space for hemoglobins

packed with hemoglobin- more oxy binded

What is the main function of red blood cells?

Allow oxy to bind using hemoglobin

Why do mature RBCs not have a nucleus

more hemoglobin = more oxy bind

What is hemoglobin + where found

oxy binding protein in rbcs

what helps oxy bind to hemoglobin

iron

Where are red blood cells produced

red bone marrow

How long do red blood cells live

120 days

damaged vessel exposes collagen fibers

platelets from a plug creating a temporary seal

clotting factors form

platelets

damaged cells

plasma

starting an enzymatic cascade

enzymatic cascade converts plasma protein from inactive prothrombin to active thrombin

thrombin enzyme converts fibrinogen to fibrin

fibrinogen vs fibrin

fibrinogen is soluble plasma protein

fibrin is insoluble thread like protein

fibrin clot forms creating a mesh that traps rbc and platelets reinforcing a plug

platelet role in blood clotting

stick to damaged blood vessel forming temporary plug

what protein forms a clot

fibrin