Topic 1- lyfestyle health and risk Flashcards
(25 cards)
why does water have a high specific heat capacity
due to the hydrogen bonds between its molecules.
why does water need a great amount of energy to increse its temprature and loses energy to decrese the temperature?
it helps livitng organisms to have a constant temperature which is essential for metabloic processes
how do animals and plants lose water?
they lose water by sweating and transpiraton processes
what are the 5 main properties of water
-metallic importance
-high specific heat capacity
-high heat of vaporization
-cohesive properties
-useful solvent
what are the 3 main uses of water?
-used as a reactant in cells
-provides structure in cells
-keeps organisms cool to maintain an optimum body temperature
what happens to the energy when water gets heated up?
the energy is used up which cools the environment where the evaporation is taking place
why does water have a high heat of vaporization
as water heats heats up, the hydrogen bonding makes it difficult to sepperate the water molecules from each other
why is water a good solvent?
the polarity and ability to form hydrogen bonds which allows ions and polar molecules to be dissolved in it
what is cohesion?
the strong attraction between water molecules due to hydrogen bonds
why does water form droplets when placed on a dry surface?
due to waters cohesion properties in which cohesion produces surface tention where water meets air
why is water adhesive?
due to its polar nature and its ability to form hydrogen bonds with other surfaces. the dipoles are attracted to oppositely charged ions. This attraction allows water to stick to materials
how and why is water dense
density prevents water from freezing from the bottom up. water is most dense at 4 degrees.
what is a double circulatory system?
where blood passes through the heart twice in one complete circuit in the body
where in the body is deoxygenated blood pumped to?
the lungs
what are coronary arteries
blood vessels that supply oxygen rich blood to the heart muscle
true or false? oxygenated blood flows into the heart from the lungs via the pulmonary artery
false. oxygenated blood flows into the heart from the lungs via the pulmonary artery
how does blood become deoxygenated
oxygen dissociates from the blood at respiring cells in the body
what is an open circulatory system?
a system where blood isnt always contained in vessels and mixes with the interstitial fluid
what happens during atrial systole
atria contract and ventricles remain relaxed. The atria contract to push any remaining blood into the ventricles
what happens during ventricular systole
the atria relaxes and the ventricles contract. the ventricles contract after a certain amount of blood is filled, increasng the pressure, closing the atrioventricular valves.
are the semilunar valves closed or open during atrial systole?
closed
what happens during diastole
both the atria and ventricles relax
