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)