Bio 38 (pt2) and 39

O2 is ____ to tissues from ____ and CO2 is ____ from tissues

delivered, blood, removed from

open circulation

when blood flows through vessel with areas of muscles contracting to pump and move blood through the vessel (found in insects, smaller/less active animals bc there is limited control of fluid movement)

closed circulation

blood flows through connected vessel and stay in its own compartment, pumped by muscular hearts (humans or animals that are larger and more active because closed CS deliver o2 at high rates to exercising tissues)

arteries

(carry blood AWAY from heart) have thick, muscular wall and large lumen

capillary

one layered, thin-walled cell wall that is ideal for exchange bc its very easy for o2 and co2 to get in or out

veins

(brings blood back to the heart) large lumen and elastic wall (not as thick as arterie)

where does pressure come from

comes from beating heart/blood flow. pressure decreases as blood flows further through the vessels and gets farther away. this creates pressure gradient (high pressure in the arteries since blood is going awafrom the heart and low pressure in the veins since the blood is going toward the heart)

blood flows fastest in the ____ because it has ____ area and ___ pressure

aorta, less, high pressure

blood flows slowest in the ____ because it has ____ area and ___ pressure

capillaries, more, low

true or false: vessels contraction doesn’t effect speed of BF

false: as vessels becomes smaller but branch more-area increases so the total area causes a decrease in BF speed and decrease in pressure

explain the usefulness of the capillaries large area

since it has a large area, it has slow speed and low pressure which gives lots of time for gas exchange

structure of fish hearts

has 2 chambers (atrium and ventricle) contains deoxy blood that pumped to gills and lamelle. the oxy blood goes directly from gills to body tissues through aorta. heat creates pressure to drive blood flow

amphibian heart structure

3 chambers (right atrium, left atrium, and ventricle) RA has deoxy blood from tissues and LA has oxy blood from lungs. blood from both atriums gets pumped into the ventricle so it has partial oxy. there is separation of circulation to lungs and body tissues but the ventricle pumps patrial oxy blood to both systems under higher pressure compared to fishes for better o2 delivery/exchange

3 points of organization of CS in land animals

1. separation circulation to gas exchange organs (pulmonary-lungs) and circulation to body tissues (systematic-body)

2. More efficient gas exchange and increased o2 delivery

3. higher metabolic/activity rates

Mammalian CS (and birds)

Right side circuit: pulmonary—heart-lungs-heart (has low o2 blood)

Left side circuit: systematic—heart-body-heart (has high o2 blood)

what does double circulation and four chambered heart mean?

double circulation means that blood goes through the heart twice in one full trip through the body (heart-lungs-heart-body-back to heart). four chambered heart means it has 2 atria (top) and 2 ventricles (bottom)

right side is ____ blood

deoxy

left side is ____ blood

oxy

receiving chambers

atrium at the top (1st chamber set)

right atrium: receives blood returning from systemic circuit

left atrium: receives blood returning from pulmonary circuit

pumping chambers

ventricles at the bottom (2nd chamber set)

right ventricle: pumps blood through pulmonary circuit (to lungs, has thin wall bc lungs don’t need as much blood)

left ventricle: pumps blood thru systemic circuit (to body, has thick walls to transport lots of blood to whole body)

Atrioventricular valves

prevent backflow of blood into atria when ventricles contract to pump blood forward

Right AV valve

in between right atrium and right ventricle

left av valve

in between left atrium and ventricle

true or false: atria contract and then ventricles contract

true

blood enters the atria from the ____. blood is pumped from the atria into the ____ through the ____ ____.

veins, ventricles, AV valves.

blood is pumped from the ventricles into the _____ to enter either the ____ (right side) or _____ (left side) circulation

arteries, pulmonary (deoxy), systematic (oxy)

cardiac muscle cells

excitable cells that can depolarizes spontaneously to create action potentials (adjacent cells connected by gap junctions allow for quick spread of APs)

Contraction requires

stimulation

SA node/SA pacemaker cells

bundles of neurons that influence and control rhythm by generating APs based on autonomic NS (sympathetic increases rate and parasympathetic decreases rate)

____ stimulate first and then the ____. then the ____ contract and after the _____ also contract.

atria, ventricles. atria, ventricles.

3 main components of metabolic rate

activity energy expenditure (calories burned from intentional, physical activity, takes up 10-30% of energy)

thermic effect of food (calories burned through digestion and storage of food eaten, takes up 10%)

resting metabolic rate (calories burned at rest, just body keeping you alive/at homeostasis, different for every person, takes up 60-70%)

true or false: its a perfect, positive, linear relationship between RMR and body size

false: its positive but not perfectly linear. rate in which tissue consumes energy is less in larger animals compared to smaller ones

endotherm

animal that produces it own body heat as a by product of metabolic reactions to maintain steady body temp. (birds and mammals)

when its cold: shivering, increasing metabolic rate, peripheral vasoconstriction (blood vessels contract and shrink so blood stops flowing) to warm up

when its hot: panting, decrease in metabolic rate, peripheral vasodilation (blood vessels get larger and blood flows through body which releases heat) to cool down

ectotherm

animals that gets heat for warmth from the environment (fishes, amphibians, reptiles)

when its cold: burrowing, seeking sunlight for warmth (change in behavior)

when its warm: lying on cool ground, seeking shade, decreasing activity, peripheral vasodilation to cool down

ectotherms have a ____ metabolic rate endotherms

lower

true or false: endotherms can be active longer over period of time and in larger range of external, environmental factors

true

ectotherm activity regulation

as temp increases, so does metabolic activity. Ectotherms can't sustain a long period of activity so, they must follow activity with long periods of inactivity (comas)

energy imbalances

intake>use: intake of energy through food—energy is stored (fat deposits)

intake<use: energy is used through activity—stored energy is used, but is storage is fully used up it can lead to starvation

things we get from food

energy, carbon, nitrogen, essential nutrient we cant make on our own

animals are

chemoheterotrophs and omnivores

3 ways of feeding

filter feeding: in aquatic animals feeding on suspended particles (sponges)

suction feeding: sucking food into mouth (fishes, whales)

active pursuit to feed: having jaws/teeth supports energetically demanding lifestyle (sharks, humans)

true or false: smaller animals have much higher metabolic rates per gram to maintain their body temp and support high activity

true