Applied Anatomy And Physiology Flashcards
What is the impact of physical activity on health and fitness
Health - the state of complete mental, physical and social wellbeing
Physical
Heart disease - occur when the coronary arteries become blocked or narrow because of the build up of fatty deposits (atherosclerosis) causing a restriction in blood flow to the heart. Regular exercise keeps the heart healthy meaning it can pump more blood around the body more efficiently
Cholesterol - LDL (low density lipoproteins) transport cholesterol in the blood. This is bad cholesterol as it is linked to an increased risk of heart disease. HDL (high density lipoproteins) transport cholesterol in the blood back to the liver to be broken down. This is good cholesterol as it lowers the risk. Regular exercise lowers LDL and increases HDL.
Social
Develop teamwork, leadership, communication and build friendships
Emotional
Release endorphins in the brain that boost mood, relieve stress and relieve anxiety
Mental
Improve decision making and problem solving
Describe the cardiac conduction system
The beat starts in the heart muscle with an electrical signal in the sinoatrial node. The impulse then passes through the atrioventricular node. The electrical impulse then passes down through some specialised fibres which form the bundle of his. The bundle branches then transport the signal to the purkinje fibres which spread throughout the ventricles causing the contraction
SAN AVN Bundle of his Bundle branches Purjinke fibres
What do chemoreceptors do
Detect an increase in carbon dioxide
What do baroreceptors do
Detect and changes in blood pressure
What do Proprioceptors do
Detect changes in muscle movement
Blood redistribution
The redirection of blood flow to working muscles (vascular shunting). Ensures that the right muscles receive adequate amounts of oxygen and co2 removal at the right time to avoid fatigue and allow continued performance in an activity.
What is venous return and the three mechanisms
The return of blood to the right side of the heart via the vena cava. This increases during exercise
Skeletal muscle pump - Muscles change shape when contracting which puts pressure on the mains creating a squeeze/pump action of blood towards the heart
Respiratory pump - As we breathe in and out pressure is put on our stomach and chest leading to pressure on nearby veins which pump blood towards the heart
Pocket valves - Ensures blood flows in the correct one way with no backflow
Starlings law
The more blood being pumped back to the heart, the more blood being pumped out, so stroke volume increases
3 types of muscle fibre
Type 1 (slow twitch) Type 2a (fast oxidative glycotic) Type 2b (fast glycotic)
Characteristics of type 1 slow twitch muscle fibres
Slow to fatigue Low force production High fat stores High levels of mitochondrial Eg. Marathon runner
Characteristics of type 2a fast oxidative glycolytic muscle fibres
High force production
Fast contraction
Quick to fatigue
Eg. Speed endurance events like 400m sprint
Characteristics of type 2b fast glycolytic muscle fibres
Very quick to fatigue
Very high force production
Very fast contraction
Eg. Weightlifting, shotput
Gaseous exchange
The exchange of gases between the alveoli and capillary via diffusion. This occurs as the gas moves from an area of high concentration to an area of low concentration.
Oxygen travels in from the alveoli and diffuses into the blood.
Carbon dioxide travels from the blood into the alveoli to be exhaled.
Huge surface area allowing for greater uptake of oxygen
Lots of capillaries surrounding alveoli for high blood supply
Very thin walls (one cell thick) so shorter diffusion pathway
Tidal volume
Volume inspired or expired per breath
Inspiratory reserve volume
Volume of air that can be forcibly inspired after a normal breath
Expiratory reserve volume
Volume of air that can be forcibly expired after a normal breath