Human Body Flashcards
What is the skeleton for
Structural strength
Creates body cavities for organ placement
Characteristics of arteries
Thick walls
Carries oxygenated blood
High pressure blood
No valves
Characteristics of arterials
Extensions off arteries which can store blood
Characteristics of veins
Thin walls
Deoxygenated blood
Valves
Characteristics of capillaries
Walls 1 cell thick
Gaseous exchange
Diffusion
Covering alveoli
What are muscles for
Attached to the skeleton via tendons allowing movement and posture control
Characteristics of red blood cells
Carry oxygen
Contains haemoglobin
No nucleus so more space for haemoglobin
What are white blood cells for
To give immunity
Lymphocytes
What are Platelets for
Clotting (closes wounds)
What is homeostasis
Body used feedback and control mechanisms to maintain a stable environment
What % of the body is made up of water
65%
What does the central nervous system comprise of
Starts at the brain works out to the rest of the body
Involved spinal chord and brain
What is the Peripheral nervous system
Senses travel from sense receptors to brain
Consists of nerves and ganglia (clusters of nerves)
Normal speed in the motor neurone
0.5m/s
Fast speed of the motor neurone
100m/s
What state are the sodium / potassium pumps in when at rest
Open
What 2 branches does the peripheral nervous system slit into
Somatic nervous system (movement)
Autonomic nervous system (automatic body functions)
What does the autonomic nervous system control
Breathing Homeostasis Blinking Reflex Heart rate Blood pressure
What are the 2 branches of the autonomic nervous system
Sympathetic division (fight or flight )
Parasympathetic (return body to normal state)
What must a sense be above the stimulate a response
Sensory threshold
What is an absolute threshold
The minimum level of stimulation To trigger a response
What will frequent exposure to a stimulation cause
Habituation
What is the endocrine system
Chemical messages
Hormones
Slower - multiple cells stimulated at once as a result
What is a proprioceptor
Detect and relay precise info about the length of extensions of each muscle