Respiration/Heart/Lungs (Bio) Flashcards
aerobic respiration
glucose + oxygen -> carbon dioxide + water
C6H12O6 + 6O2 -> 6CO2 + 6H2O
- exothermic
- 38 ATP released
where to get reactants for aerobic respiration
glucose from digestion of food (stored in muscles and liver as glycogen)
oxygen from blood
where does aerobic respiration take place
in mitochondria
- more mitochondria in a cell = more metabolically active
why do boys need to eat more than girls
more muscle mass/respiration/glucose needed
5 uses of energy in body
anabolic reactions: synthesis of larger molecules from smaller ones (protein synthesis)
catabolic reactions: break down larger molecules into smaller ones (digestion)
muscle contraction (movement, peristalsis, breathing)
maintain stable body temp. (shivering, sweating)
active transport (moving mineral ions from soil into root hair cells)
aerobic respiration during exercise
heart rate increases - increase blood supply to and from muscles
arteries supplying active muscles dilate (get wider) - for same reasons
breathing rate and depth increase - increase grass exchange at lungs
muscles convert stored glycogen-> glucose
anaerobic respiration (animals)
glucose -> lactic acid
C6H12O6 -> 2C3H6O3
- exothermic
- 2ATP released
- v fast- less bonds broken
where does anaerobic respiration take place
cytoplasm
lactic acid causes…
muscle fatigue (tire and stop contracting as efficiently)
pain (soreness due to reduced pH)
oxygen debt
waste lactic acid needs to be removed from the body and oxygen is needed for this to happen
- lactic acid from anaerobically respiring muscles diffuses into the blood
- converted back to glucose in the liver (using ATP)
anaerobic respiration in plants (and why is this needed? and other uses?)
fermentation:
glucose -> ethanol + carbon dioxide
C6H12O6 -> 2C2H6O + 2CO2
- used when plants are flooded so there is very low oxygen concentration in soil
- used in manufacture of alcoholic drinks / bread
aerobic vs anaerobic respiration:
diffusion
NET movement of particles
down a concentration gradient
through a partially/selectively permeable membrane
until an equilibrium is reached
side length vs SA:V ratio
as side length increases, SA:V ratio decreases
diffusuion in unicellular organisms
- relatively large SA:V ratio
- relatively low distance between cell membrane and centre of cell (substances do not have to travel very far)
- can enter directly from environment, waste products leave the same way
diffusion in multicellular organisms
small SA:V
large distance
exchange cannot happen fast enough
so have exchange surfaces and transport systems to accommodate this
how small intestine is adapted for exchange
highly folded surface and cells with highly folded cell membrane (increase SA)
1 layer of epithelial cells on the surface (decrease diffusion distance)
good blood supply (maintain concentration gradient)
how gills adapted
each gill has lots of smaller filaments (increases SA)
good blood supply
how are roots adapted
highly branched root network
surface covered with root hair cells
(both increase SA)
how are leaves adapted
little hairs (SA)
stomata allow gases in and out (Dd)
spongy mesophyll layer allows air to circulate inside the leaf (Dd)
Ficks Law
rate of diffusion proportional to:
surface area x concentration difference / diffusion distance
so
rd prop to surface area
to concentration difference
to 1 / diffusion distance
function of lungs
enable breathing
move air in and out of lungs (ventilation)
provide a surface area for gas exchange
inhalation
diaphragm contracts and moves down
- increase volume of chest cavity
- decreases pressure of chest cavity
- air moves in and fills lungs
+ intercostal muscles contract - ribs move up and out
exhalation
diaphragm relaxes and moves up
- decrease volume of chest cavity
- increase pressure of chest cavity
- air moves out and empties lungs
thorax
chest cavity
intercostal muscles
external and internal intercostal muscles
- are an antagonistic pair (work against each other)
externals contract
- ribs move up and out (inhalation)
internals contract
- ribs moves down and in (exhalation)
composition of inhaled and exhaled air
what is heart?
walls made of?
organ (group of tissues working together) that pumps blood around the body
- walls are almost entirely muscle (need oxygen to function which is supplied by coronary arteries)
movement of blood through the heart (order)
vena cava
right atrium
right ventricle
pulmonary artery
lungs (becomes oxygenated)
pulmonary vein
left atrium
left ventricle
aorta
body (becomes deoxygenated)
arteries VS veins
carry blood away from VS to the heart
high pressure VS low pressure
thick walls & lots of muscluar tissue VS thin walls and not much muscular tissue
narrow lumen VS wide lumen
thick elastic wall VS thin elastic wall
no valves VS valves
valves
in veins
- prevent back flow of blood
- maintain unidirectional travel of blood
endothelial cells
line blood vessels
- v smooth
capillaries
allow the exchange of molecules between the blood and the body’s cells - molecules can diffuse
- 8-10 micrometers lumen (same as RBCs)
- have fenestrations (like windows that WBCs can fit through)
- one cell thick walls
what is respiration
The process by which organisms RELEASE energy from food
what is blood
(BROKEN)
tissue (group of similar cells working together to perform a particular function
role of blood
transport useful substances to every cell of the body
remove harmful waste substances
transfer heat from ‘active’ organs to cooler parts of the body (so enzymes don’t denature)
composition of blood
55% plasma
45% RBC
<1% WBC & platelets
RBCs
WBCs
platelets
no nucleus
small fragments of cells
help blood to clot at the site of the wound (prevent infection & blood loss)
plasma
mostly water
It carries all the platelets and red and white blood cells around the human body.
It also carries hormones, dissolved glucose for respiration, dissolved salts and enzymes around the body.
Waste products like carbon dioxide are also transported in the plasma
CHD
when (walls of) coronary arteries supplying the heart muscle become narrowed or blocked by a build up of cholesterol (fatty material)
atheroma / plaque (not the same thing)
build up of cholesterol and narrowing of lumen
types of cholesterol
HDL which transport cholesterol from blood vessels to liver for elimination (good)
LDL lead to deposition of plaque in blood vessels (bad)
from liver and dietary sources
statins
stents
remember to say CLOGGED artery
and that it increases/maintains blood flow
5 ways heart is adapted
valves prevent back flow of blood
septum prevent mixing of oxygenated and deoxygenated blood
large no. coronary arteries supply blood and remove waste products
thick ventricular walls to pump blood out of heart (contrasted with atria which only pump to ventricles)
wall of left ventricle thicker than wall of right to pump blood around entire body (right ventricle only pumps to lungs)
SA node (sinoatrial node)
where is it?
hearts natural pacemaker:
- controls pumping of heart
- located in right atrium
- sends out electrical impulse which spreads to surrounding cells, causing them to contract
problems with beating of heart
too slow- not enough oxygen
too fast- can’t pump efficxticely
irregular- body doesn’t get regular/constant supply of oxygen
artificial pacemaker
small battery operated electrical device implanted in patient’s chest, just under skin with wires that send out electrical impulse which stimulate heart to contract
Pros enable normal function
Cons: surgery, short lasting
problems with valves
can’t close- backflow of blood
can’t open- restrict flow of blood
both put extra strain on heart
solutions for valves
heart transplant
artificial heart
nasal cavity
includes nose and mouth
produce mucus and hair to catch debris
ribs
protect lungs
trachea
connect nasal cavity with lungs
produce mucus and traps debris
lined with cilia (tiny hairs that waft mucus up lung)
bronchus
connects trachea with lungs
left and right branching into each lung
lined with goblet cells (produce mucus) and cilia
bronchiole
connect bronchus with alveoli
don’t say diffusion distance, say …
diffusion distance of the exchange surface
how are alveoli adapted
lots of them - increase SA - quicker diffusion and more GE
thin walls - low Dd
constant supply of blood - maintain CG - constant rate of diffusion
constant air flow - same thing
where does gas exchange occur
alveoli
atherosclerosis
build up/hardening of fatty material in the WALLS of the coronary arteries
Explain the effect of a partly blocked coronary artery on the human body. (6)
