biology module 3 Flashcards
cartilage
involved in supporting trachea and Bronchi, prevents lungs from collapsing when there is a drop in pressure
ciliated epithelium
present in bronchi , bronchioles, trachea involved in wafting mucus secreted by goblet cells to the throat
Goblet cells
cells present in the trachea, bronchi and bronchioles involved in mucus secretion to trap bacteria and dust to reduce the risk of infection with the help of lysozyme which digests bacteria
smooth muscle
their ability to contract enables them to play a role in constricting
the airway, thus controlling its diameter as a result and thus controlling the flow of
air to and from alveoli
Elastic fibers
– stretch when we inhale and recoil when we exhale thus controlling
the flow of air
Vital capacity
– the maximum volume of air that can be inhaled or exhaled in a single
breath. Varies depending on gender, age, size as well as height
Tidal volume –
– the volume of air we breathe in and out at each breath at rest
Breathing rate
the number of breaths per minute, can be calculated from the spirometer
trace by counting the number of peaks or troughs in a minute
residual volume
The volume of air which is always present in the lungs
what is hydrostatic pressure and oncotic pressure
hydrostatic pressure - pressure that a fluid exerts when pushing against a side of a vessel
Oncotic pressure- pressure created by osmotic effects of the solutes
cardiac output
fibiliration
myogenic
amount of blood pumped around the body
beating out of order
heart can beat w/0 brain sending impulses
describe the cardiac cycle
the pacemaker cells start on the right side of the heart spreading an electric wave, the electric wave spreads over the atria walls causing the muscle to contract, at AV valves impulses are held briefly to allow blood to move into ventricles, the wave then spreads through purkinje fibres and across the walls pushing the blood up + out
describe systole cycle
Diastole- all muscles relax , volume increases, pressure drops in chambers, SL valves shut
Atrial systole- atria contract volume decreases , pressure increases to be highest in the atria , AV valves open
ventricular systole- sv valves open , ventricles contract, pressure increases in ventricles as volume decreases , valves snap shut
Cardiac muscles consist of…
fibres that branch to form cross ridges which help transport stimulus around the heart - ensures muscles can squeeze rather than a simple reduction in length , numerous mitochondria , muscle cells are separated by intercalated discs - synchronised contraction