Week 1 (introduction to physiology and homeostasis) Flashcards
Define anatomy
The science of body structures and their relationships.
Define physiology
The science of body functions.
Name the 6 levels of structural organisation
- chemical
- cellular
- tissue
- organ
- system
- organism
Describe the chemical level
Atoms (smallest unit of matter)
Molecules (2 or more atoms)
Will occur repeatedly throughout all different cell types.
Describe the cellular level
Cells are the basic structural and functional units of an organism.
They are specialised for specific functions.
Describe the tissue level
Tissues are groups of cells and surrounding material. They work together to perform a particular function. There are 4 basic types; epithelial, connective, muscular and nervous.
Describe the organ level
Organs are composed of 2 or more types of tissue.
They have specific functions and a recognisable shapes.
Describe the system level
A system is made up of many organ components that have a common function.
Describe the organism level
All the parts of our body functioning together.
Describe the components and functions of the integumentary system
Components: skin, hair, fingernails, sweat glands
Functions: protects body, regulate body temperature, sensation, insulation
Describe the components and functions of the skeletal systems
Components: bones, joints, cartilage
Functions: supports, protection, aids movement
Describe the components and functions of the muscular system
Components: skeletal muscle tissue
Functions: body movement, posture, heat production
Describe the components and functions of the nervous system
Components: brain, spinal cord, nerves, specialised organs
Functions: regulate body activity, detect and interpret changes.
Describe the components and functions of the endocrine system
Components: hormone producing glands
Functions: regulate body activity
Describe the components and functions of the cardiovascular system
Components: heart, blood vessels, blood
Functions: transport oxygen and nutrients, remove waste, regulation
Describe the components and functions of the lymphatic system
Components: lymphatic fluids, spleen, thymus
Functions: return proteins and fluid to blood, transport lipids from GI tract, immune cells
Describe the components and functions of the respiratory system
Components: lungs, pharynx, trachea
Functions: transfer of oxygen and carbon dioxide, regulation of acid-base balance
Describe the components and functions of the digestive system
Components: GI tract, accessory organs
Functions: physical and chemical digestion of food, nutrient absorption, waste elimination
Describe the components and functions of the urinary system
Components: kidney, ureter, bladder
Function: produce, store and eliminate urine, eliminate waste, regulate fluid balance
Describe the components and functions of the reproductive system
Components: gonads and associated organs
Functions: produce and store gametes, produce hormones
Name and describe the 6 basic life processes
Metabolism: sum of all chemical processes in the body
Responsiveness: ability to detect and respond to change
Movement: motion at different levels
Growth: increase in body size
Differentiation: development of a cell from unspecialised to specialised
Reproduction: production of new cells through cell division
What is homeostais?
The maintenance of relatively stable conditions in the body’s internal environment.
Why is homeostasis important?
Maintains life
Detects changes before a critical state is reached.
Make sure all systems are working optimally and efficiently.
Restores the normal state of the body after disturbances.
Which systems are the most important in homeostasis and why?
Endocrine and nervous system as they send messages to the body and they respond quickly.
Describe the disturbances that can occur to the body (give examples)
Disturbances is normally mild and temporary and can happen to both the external and internal environments.
Prolonged and intense disturbance can affect our health.
External environment: e.g., temperature
Internal environment: e.g., insufficient blood glucose
How do we regulate our internal environment?
Feedback systems/loop = cycle of events (monitor, evaluate, effect a change, re-monitor)
Control systems = maintain a variable within a given range following disturbances.
Define stimulus
The thing that changes the controlled condition
Define controlled condition
The variable that is being changed.
Name the three components of a feedback loop
Receptor
Control centre
Effector
Describe receptors
Monitors change in a controlled condition
Sends input to a control centre
Afferent pathway
Describe the control centre
e.g., brain
Sets the ‘set point’ of the variable
Evaluates input from receptors
Efferent pathway
Describe the effector
Receives output from the control centre
Produces a response that changes the controlled condition
Describe a negative feedback loop
Change occurs in the opposite direction to the original stimulus.
Decrease in function or output
E.g., blood pressure ruses
Describe a positive feedback loop
Change occurs in the same direction to the original stimulus.
Increase in function or output.
E.g., childbirth
What does homeostasis maintain in terms of body fluids?
The body fluids volume and composition
Name the two types of body fluids
Intracellular fluid = inside cells
Extracellular fluid = outside cells
Give examples of extracellular fluids
Interstitial fluid: between cells of tissues
Blood vessels: plasma
Lymphatic vessels: lymph plasms
CNS: cerebrospinal fluid
Joints: synovial fluid
Eyes: aqueous humor and vitreous body
What happens when there are homeostatic imbalances?
Development of illness, infections and diseases.
Name the three ways to describe sensory receptors
Structure
Location
Type
Describe the microscopic structure of sensory receptors
Free nerve endings of first-order
sensory neurons
Encapsulated nerve endings of first-order sensory neurons
Separate cells that synapse with first-order sensory neurons
Name the three locations of sensory receptors
Exteroceptors
Interoceptors/visceroceptors
Proprioceptors
Describe exteroceptors
Located at or near the external surface of the body.
Provide information about the external environment
Examples: hearing, vision, smell, taste, touch, pressure, temperature, pain.
Describe interoceptors
Located in blood vessels, visceral organs, muscles and the nervous system.
Provide information about the internal environment.
Generated nerve impulses not usually consciously perceived.
Describe proprioceptors
Located in muscles, tendons, joints and inner ear.
Provide information about body position, muscle length and tension, and the position and movement of joints.
Name and describe the 6 types of stimulus of sensory receptors
Mechanoreceptors: sensitive to mechanical stimuli and monitor the stretching of blood vessels and internal organs.
Thermoreceptors: detect changes in temperature.
Nociceptors: respond to painful stimuli from physical or chemical damage to tissue.
Photoreceptors: detect light that strikes the retina of the eye.
Chemoreceptors: detect chemicals in the mouth, nose and body fluids.
Osmoreceptors: detect the osmotic pressure of body fluids.
