Basic Physiological Principles Flashcards
What is Physiology?
Study of function and activity of life or living matter (such as organs, tissues, or cells) and of the physical and chemical reactions involved
outline the basic structure of the human body
Chemicals (molecular)
Cells
Tissues
Organs
Organ Systems
describe the human body at a molecular level
-The human body is composed of atoms organized into molecules
-Atoms and molecules undergo chemical reactions
describe cells
-Basic living units
-Smallest subdivision able to carry out all life processes
-Contain organelles
-Specialized for specific physiological roles
define organelles
Structures that have specific functions
why is specialisation important for cells?
it allows cells to control reactions in different ways to carry out specialist functions
describe tissue
-Groups of specialised cells (cells with interconnected function)
-Interaction among cells leads to functions single cells cannot effectively do alone
give examples of different tissues
-nervous tissue
-muscle tissue
-connective tissue
-epithelial tissue
describe epithelial tissue
-forms body surfaces e.g. skin, oral mucosa
-secrete substances e.g. in gut
-absorb substances e.g. in respiratory system
-allow movement through cilia
describe connective tissue
-very diverse
-produce extracellular matrix which provides structure
-cartilage and bone are connective tissues
-helps with signalling in body
-contains fibroblast which helps determine function of cells
describe muscle tissue
-muscles contract and allow movement
-can be cardiac, smooth or skeletal
-generates tension, movement and heat
describe nervous (neuronal) tissue
-controls responses of body
-made up of nerve cells which together, send signals from one part of the body to other parts
-helps maintain functions of parts of body
describe organs
-structures consisting of at least two tissue types
-perform a specific function related to the whole body
describe organ systems
-groups of organs performing related functions
-enable basic functions needed to maintain overall homeostasis
name 10 major organ systems
-nervous
-endocrine
-respiratory
-integumentary
-urinary
-digestive
-immune
-musculoskeletal
-circulatory
-reproductive
what is the nervous system for?
Communication and control
what is the endocrine system for?
Communication and control
what is the respiratory system for?
Gas exchange, pH balance
what is the integumentary system for?
Barrier between interior of body and exterior, thermoregulation
what is the urinary system for?
Waste removal, water and ion balance
what is the digestive system for?
Obtain raw materials from exterior
what is the immune system for?
Protect body from foreign substances, other organisms and cancer cells
what is the musculoskeletal system for?
Movement, structure, support, protection, heat generation
what is the circulatory system for?
Transportation of most materials throughout body
what is the reproductive system for?
continuation of the species
describe the internal environment
-interior of body and environment in cells
-about 67% water
why is a lot of the internal environment water?
-provides a liquid environment
-high specific heat capacity SO doesnt change temp easily
-polar solvent SO only dissolves certain substances SO body has control over components of internal environment
what are attributes of the internal environment?
-nutrients
-waste
-O2 and CO2
-temp of 37°C
-pH of 7.4
-salts
-fluid volume
what is homeostasis?
Maintaining a stable internal environment
what does a sensor do?
monitors internal conditions, detects changes
what does the integrating centre (controller) do?
changes are transmitted to controller and it integrates all info
what does the effector do?
responds to changes and the activity of the effector results in return of condition to normal level
name the 3 regulatory mechanism components
-sensor
-intergrating center (controller)
-effector
what is feedback?
return of the output to the input part of a system
what is negative feedback?
A response to a change in the body that counteracts or opposes the initial change - it is the most common type of feedback
what are examples of negative feedback?
-insulin in blood glucose regulation
-temperature regulation
insulin in blood glucose regulation
temperature regulation
does homeostasis mean that conditions all remain the same?
no, it is a dynamic process where body is constantly trying to make the conditions return to their original levels
what is positive feedback?
feedback where the change in condition leads to a response from the effector that amplifies the change
describe childbirth as an example of positive feedback
when body is read to give birth:
-pituitary glands release oxytocin which causes uterine contractions
-this produces prostaglandins and stimulate cervical stretch
-these both further stimulate the contractions which further produce prostaglandins and stimulate cervical stretch
explain blood clotting as an example of positive feedback
the end point is a blood clot so positive feedback drives the process until the clot is formed
what happens if homeostasis is not maintained?
diseases such as diabetes or cancer
what is diabetes mellitus
Metabolic disorder of carbohydrate metabolism
what is a characteristic of diabetes mellitus
Hyperglycaemia (🡹 blood glucose)
what is the consequence of diabetes mellitus
High morbidity (illness) & mortality (death)
describe diabetes as failed homeostasis
-feedback mechanism does not work becasue the sensor for high levels of glucose is not working or the effector (liver) does not release insulin as a response
-diabetes mellitus is the metabolic disorder of carbohydrate metabolism and it is characterised by hyperglycaemia
what oral disease is due to diabetes
Gum diseases (periodontitis & gingivitis) very common:
-Red & swollen gums
-Increased bleeding while brushing
-Increased plaque
what does gum disease lead to
Gum disease is followed by:
-tooth decay
-Inflamed & sore tissues, ulcers
describe cancer as failed homeostasis
-caused by mutations in DNA of malignant cells
-causes changes in behaviour of cells including communications with other cells
-disrupts tissue homeostasis so normal tissue structure breaks down so cancer spreads
