biology gas exchange and circulation Flashcards
raspitory surfaces
must be thin and moist for quicker diffusion of O2 and CO2
gills
žiaunos
gill filaments bearing many platelike lamellae
gills absorb O2 dissolved in water
countercurrent exchange
the transfer of a substance such as oxygen between two fluids flowing in opposite directions
operculum
gill cover
advantages of breathing air
air contains a much higher concentration of O2
air is much lighter and easier to move our body within (less energy is used)
diaphragm
separates the abdominal cavity from the thoracic cavity
helps ventilate the lungs
mucus and cilia
in the raspitory passeges protect the lungs from contaminants and dust
inhalation
the contraction of rib muscles and the diaphragm expands the thoracic cavity, reducing air pressure in the alveoli and drawing air into the lungs
exhalation
the relaxation of rib muscle and the diaphragm contract the thoracic cavity, increasing air pressure in alveoli, leading to exhalation
vital capacity
the maximum volume of air that can be inhaled and exhaled with each breath
normal blood pH
about 7.4
CO2 + H2O <–> H2CO3 <–> H+ + HCO3-
how our brain indicates the amount of CO2 in our blood?
MEDULLA by sensing the pH of our cerebrospinal fluid
Medulla oblongata - the bottom-most part of your brain
why molluscs blood is blue?
oxygen is bound to copper-containing pigment, which is blue
fish heart
two-chambered
heart pumps blood in a single circulation
land vertebrates
double circulation
pulmonary (heart and lungs) and systematic circuit (heart and the rest of the body)
blood flow through the double circulatory system in humans
- drains from the superior vena cava (from the head and arms) or inferior vena cava (from the lower trunk and legs) into the right atrium
- moves out to the lungs via the pulmonary artery
- returns from the lungs to the left atrium through the pulmonary vein
- leaves the heart through the aorta
diastole
blood flows from the veins into the heart chambers
systole
contractions of the atria push blood into the ventricles, and then stronger contractions of the ventricles propel blood into the large arteries
valves
vožtuvai
semilunar valve
AV valve
cardiac output
the volume of blood that each ventricle pumps per minute
heart rate
number of heartbeats per minute
AV valve
between atrium and ventricle
semilunar valve
between ventricle and pulmonary artery / aorta
SA node
sinoatrial node
generates electrical impulses in atria
set the rate of heart contractions
AV node
atrioventricular node
relays signals from AV node to the ventricles
trigger ventricular contractions
ECG
electrocardiogram
stroke
death of the brain tissue due to lack of O2
atherosclerosis
During the course of this disease, fatty deposits called plaques develop in the inner walls of arteries, narrowing the blood vessel through which blood can flow
blood consists of
plasma
red blood cells
white blood celss
platelets
amenia
low number of red blood cells
hormone erytropoietin (EPO)
stimulates the bone marrow to produce
more red blood cells
fibrin inactive form
fibrinogen
leukemia
cancer of white blood cells
