Explain the role of neurotransmitters in stimulating skeletal muscle contraction.
The chemicals that are used for communication between a neuron at the synapse and another cell.
Acetylcholine transfers the action potential from the motor unit to the muscle cells, allowing for contraction. It changes the electrical impulse to a chemical stimulus, as well as allowing calcium to be released.
Cholinesterase breaks down acetylcholine which allows the muscle to stop contracting.
Explain how skeletal muscle contracts by the sliding filament theory?
Myosin filaments have myosin heads which are prevented from binding to the actin due to tropomyosin.
Troponin neutralizes tropomyosin when calcium is present, which is stimulated by a nerve impulse
This allows the myosin heads to bind to the actin, which stimulates the breakdown of ATP and releases energy
This binding shortens the muscles causing muscle contraction
This stops when the calcium ions are removed
List characteristics of type 1 (slow twitch) muscle fibres
slow contraction speed
small size of motor neuron
high fatigue resistance
used for aerobic activity
low force production
highly efficient
high mitochondrial density
high capillarization
high oxidative capacity
List the functions of the skeleton.
Protection of organs
Attachment for muscles
Support of organs and tissues
Movement for muscles
Store minerals
Produce blood cells
State the four types of bone.
Long (humerus)
Short (carpals)
Flat (ribs)
Irregular (vertebrae)
State the common anatomical positions.
proximal - closer to center
distal - further away
medial - closer to midline
lateral - further from midline
inferior - below/further away from head
superior - above/closer to head
posterior - behind
anterior - in front
List the types of connective tissue.
Tendons (MTB muscle to bone)
Ligaments (BTB bone to bone)
Cartilage (reduces frictions and creates cushion)
List the different types of joint
Fibrous (fixed), no movement allowed
Cartilaginous, limited movement allowed
Synovial, most common and allows most movement
List the different types of synovial joint
Hinge, elbow
Pivot, neck
Ball and Socket, shoulder
Condyloid, wrist
Saddle, thumb
Gliding, tarsals
List the types of movement within the body.
Adduction, towards midline
Abduction, away from midline
Flexion, make angle smaller
Extension, make angle larger
Pronation, palm down
Supination, palm up
elevation, shrug (up)
depression, down
rotation, turning on a long axis
circumduction, turn wrist
eversion, pointing outwards
inversion, pointing inwards
plantar flexion, stand on toes
dorsi flexion, stand on heels
Outline blood supply to the brain.
Left and Right carotid arteries
Left and Right vertebral arteries
BBB (blood brain barrier)
State the principal sources of energy for brain cells.
Glucose and Oxygen
ATP
State the function of the principal parts of the brain.
Brain Stem - respiratory and cardiovascular control
Thalamus - sensations
Hypothalamus - autonomic nervous system, BP, heart rate
Cerebrum - thinking, language, emotion, motivation
Frontal lobe - reasoning, planning, speech, movement
Parietal lobe - somatic and motor
Occipital lobe - visual and association
Temporal lobe - auditory and memory
List the functions of the skin.
Regulation of Body Temperature
Protection and immunity
Sensation
Excretion
Synthesis of Vitamin D
Define the types of muscle contraction.
Isotonic - change in muscle length
Concentric (shorter)
Eccentric (longer)
Isometric - no change in length
Isokinetic - produce movement at constant speed (rare)
Explain reciprocal inhibition.
Agonist and Antagonist pairs, agonist move the muscle and antagonist bring it back to resting.
What is the composition of blood?
Erythrocytes (red blood cells) (44%)
Leukocytes (white blood cells) (0.5%)
Platelets (0.5%)
Plasma (55%)
Describe intrinsic and extrinsic regulation of heart rate.
Intrinsic (pacemaker system)
Extrinsic (autonomic nervous system)
What is venous return?
The amount of blood returned to the right side of the heart.
What is stroke volume?
The amount of blood pumped by each ventricle per beat (liters)
Explain cardiovascular drift.
Where heart rate increases, stroke volume decreases but cardiac output remains the same. This is due to heat and prolonged endurance exercise. It can be minimized by hydration.
Define systolic and diastolic blood pressure.
Systolic - contract and spill (higher then Di during exercise)
Diastolic - relax and fill
Describe the cardiovascular adaptations resulting from endurance exercise training.
resting heart rate decreases
stroke volume increases
increased capillarization
arterio-venous oxygen difference increases