1 - homeostasis Flashcards
Definition of anatomy
Structure of components of living organisms and the relationship these components have to another
Definition of Physiology
Function of the components of living organisms. Investigates how organisms regulate their internal environment to maintain homeostasis
What is the principle of complementarity of structure and function?
The structural design of a body part determines what kind of function it can perform
What are the six levels of structural organisation?
1) Chemical level. Involves atoms and molecules
2) Cellular level - smallest living units in the body
3) tissue level - Group of cells working together to perform specific functions. Epithelial, connective, muscle, nervous.
4) organ level - two or more tissues working together
5) organ system - Group of organs working together
6) organism - individual lifeform
Definition of homeostasis
Maintenance of relatively stable conditions to ensure the bodies internal environment is constant despite changes in and out the body
Second definition of homeostasis
maintaining bodies internal environment within physiologically defined limits
What is physiologically defined limits?
Range of conditions in which the body can function optimally such as body temperature, blood pressure, blood glucose concentration, mineral level, water level, blood volume and gaseous concentration.
What is homeostatic maintenance?
Bodies ability to regulate its internal environment and involves the 11 organ system. nervous and endocrine system play huge roles in maintaining homeostasis
What is a feedback system?
It is a homeostatic control mechanisms that detect deviations from a setpoint and initiates responses to counteract these deviations so that it can restore the internal environment to its optimal state
What is a controlled condition?
Monitored condition in the feedback system such as the physiologically defined limits
What is a stimulus?
Any destruction that causes a change in a controlled condition
Describe the feedback loop.
Stimulus disrupts homeostasis by increasing or decreasing a controlled condition.
controlled condition is monitored by receptors which send nerve impulses or chemical signals to a control centre.
control centre receives the input and provide nerve impulses or chemical signals to the effector.
the effector brings about a change or a response that alters the controlled condition.
What does a negative and positive feedback do?
Negative feedback reverses a change.
positive feedback reinforces a change.
Describe the control of body temperature. Negative feedback.
RCA.
- receptor - temperature sensitive cells in skin and brain sends information to affront pathway to control centre.
- Control centre - receives input in thermoregulatory centre in hypothalamus and send information to affector.
- effector - if body temp rising - receives the output and the sweat glands evaporate sweat, and body temperature falls. If body temperature falling - shivering begins from the skeletal muscles.
Describe the blood clotting process positive feedback.
Damaged cells in blood vessel wall releases chemicals that begin the clotting process.
The chemicals start chain reactions in which cells, cell fragments and soluble proteins in the blood begin to form clot.
As clotting continues each step releases chemicals that further accelerates the process.
This process is a positive feedback loop that ends with the formation of a blood clot which patches the vessel wall and stop the bleeding.
Describe process of uterine contractions during labour negative feedback.
stimulus - contractions of the wall of the uterus forced the babies head or body into the cervix.
controlled condition been affected - stretching off the cervix.
Receptors - stretch sensitive nerve cells in the cervix send nerve impulses to the brain.
control centre - Brain interprets input and releases oxytocin to the effector which is muscles in the wall of the uterus and therefore the muscles contract more forcefully.
response - babies body stretches the cervix more.
Increased stretching of the cervix causes the release of more oxytocin which result in more stretching of the cervix.
Definition of disease.
Body fails to function normally and is categorised by a set of symptoms and signs.
Definition of a disorder.
Destruction or abnormality in the normal functioning of a body or mind.
Definition of pathology.
Study of disease characteristics, causes and effects.
What do medical practitioners do?
Use anatomical physiological, chemical and psychological information to diagnose treat and prevent disease and disorders.
What are signs?
Observed or measured objectively. Fever, cough rash.
What are symptoms?
Experienced subjectively.. Headache, dizziness, insomnia, vomiting.
What is ageing?
Progressive decline in the bodies ability to restore homeostasis.
