Lecture Notes: Medical Imaging, Anatomy & Physiology - Vocabulary Flashcards

Vocabulary flashcards covering key terms from the notes on anatomy, physiology, body cavities, planes, organization, and basic imaging concepts.

Cell

The smallest unit of living things; the basic unit of structure and function in organisms.

Tissue

A group of similar cells that work together to perform a common function. 4 main types, muscle, connective, epithelial and nervous

Organ

A discrete structure composed of at least two tissue types (usually four )that performs a specific function.

Organ system

A group of organs that work together to accomplish a common function

Anatomy

The science dealing with the structure of body parts and their relationship to one another

developmental anatomy - dicusses structural changes in a lifespan, eg: embryology

microscopic anatomy - study of structures to small to be seen with naked eye, eg: histology and cytology

gross anatomy - study of large structures that can be seen with the naked eye, which is surface, regional, and systemic anatomy.

surface (study of internal structures as they relate to overlying skin surface), clinicians use it to locate suitable blood vessels to check pulse etc.

regional, study of structures in a particular region of body

systemic, study of structures in a system of body

Physiology

The science of the functions of body parts and events occuring at cellular level

How does physiology depend on anatomy

The function of a structure (because physiology is about bodily function) is promoted or prevented by its anatomy

For example, oxygen and carbon dioxide diffuse across a thin membrane in lungs to reach bloodstream, not through skin because skin is too thick

Integumentary system (function and organs involved)

protects internal organs from drying out
protects body against infections,heat, sun and chemicals
protects deep tissues from injury
synthesises vitamin D
has cutaneous receptors (such as pain/pressure receptors)
contains sweat and oil glands

skin, hair, nails

Skeletal system (function and organs involved)

provides framework to muscles for movement
provides protection and support to internal organs and tissues

bones also store minerals and blood cells are produced inside bone marrow

organ; bones

muscular system (function and organs involved)

allow manipulation of environment, locomotion and facial expressions
generates heats
maintains posture

organ: mucles

Lymphatic system (function and organs involved)

collects leaked fluid from blood and supplies it back to blood
removes debris in lymphatic fluid
contains lymphocytes (associated with immunity)

organs(6) - thymus, spleen, red bone marrow, lymphatic vessels, thoracic duct, lymph nodes

Digestive system

breaks down complex food substances into smaller simpler molecules to be absorbed into bloodstream and supllied to body cells
excretes undigested food as feces

organs: oral cavity, oesphagus, stomach, duodenum, small and large intestine, rectum, anus and liver

Respiratory system (function and organs involved)

constantly supplying blood with oxygen and removing carbon dioxide from body

nasal cavity, pharynx, laryns, bronchus, trachea, lungs

Nervous system (function and organs involved)

Fast acting control system of the body
responds to internal and external changes/stimuli by activating muscles and glands

brain, spinal cord, nerves

Endocrine system (function and organs involved)

has GLANDS that secretes hormones that help regulate
- metabolism of body cells
- growth
- reproduction

pancreas, ovary, testicles,

GLANDS - pineal, pituitary, adrenal, thyroid, thymus

cardiovascular system (function and organs involved)

blood carries, O2, CO2, waste, water, nutrients
heart pumps blood
blood vessels transport blood

heart, blood vessels

Urinary system (function and organs involved)

excretes nitrogenous wastes from body

regulates water level, acid base balance and electrolytes of blood

kidneys, bladder, urethra, ureter

Reproductive system (function and organs involved)

male and female work tgt to create offspring

Male;

testes produces male sex hormones and sperm
vas deferens delivers sperm to urethra
organs: prostate, vas deferens, testes, scrotum, penis, urethra

female;

fallopian tube site of fertilisation
ovary produces ovum and female sex hormones
uterus site of implantation of embryo
mammary glands in breasts produce milk to nourish newborn

ovary, uterus, fallopian tubes, cervix, vagina, breasts

Function and pathway of negative feedback mechanism

Function: prevent severe changes in the body

1. stimulus causes change in variable

2. receptor responds to stimuli and detects change

3. information sent along afferent pathway to control centre

4. control centre determines set point of variable and appropriate response

5. information is sent along efferent pathway

6. effector carries out response determined by control centre to reduce effect of stimulus

7. variable returns to set point

Positive feed back mechanism (PFM)

amplifies original stimulus
causes a linked sequence of events
causes variable to deviate further from set point

PFM for Labor Contractions

During labor, oxytocin (hormone produced in hypothalamus) is secreted to intensify labor contractions
Causes contractions to become more frequent and intense

Increases frequency of contractions causes more oxytocin to be secreted

This continues until baby is born

Childbirth ends stimulus for oxytocin released

PFM for blood clotting

When a break or tear occurs in blood vessel wall, platelets adhere to site and release chemicals

released chemicals attract more platelets

this continues until a platelet plug is fully formed

X-RAYS (mechanism, function, characteristic of image, pros, cons)

mechanism:
uses short electromagnetic waves called x-rays

function:
detect broken bones
used in mammography to find breast tumors
measure bone density to check for osteoporosis (porous bones)
not used for soft tissue unless got contrast medium (i.e. barium sulfate)

image: 2D
bones or dense structures appear as a light area
hollow air containing structures (i.e. lungs) appear dark

pros/cons
causes radiation exposure

DSA (mechanism, function, characteristic of image, pros, cons)

DSA = Digital Subtraction Angiography

function
visualize blood vessels using X-ray of CT

mechansim
injection of x-ray absorbing contrast agent
digitally subtract before and after image of blood vessel
gives clear image of blood vessel

pros:
detects blood vessel abnormality (blockage in artery)

cons:
expensive
time consuming
adverse rxn to medium can occur

CT scan (mechanism, function, characteristic of image, pros, cons)

CT = computed tomography

a series of X-ray images reconstructed using computer

provides detailed cross sectional pictures of scanned body regions
used for image of soft tissue, bone and blood vessel
NOT used for nervous tissue or joints

cons
provides more radiation exposure than x-ray

PET scan (mechanism, function, characteristic of image, pros, cons)

PET = Position Emitted Tomography

uses gamma rays emitted by radioactively tagged tracer molecules

Tracer used depends on reason for scan
1. radioactive glucose : detects cells with high metabolic activity such as cancer cells
2. florbetapir : visualize beta amyloid plaques in brain (linked to alzheimer)

function:
detect cancer or monitor response to cancer treatment
sometimes to diagnose alzheimer
explore/study brain function

cons:
radiation exposure
poor image resolution

MRI and fMRI (mechanism, function, characteristic of image, pros, cons)

MRI = magnetic resonance imaging

uses powerful magnets and radiowaves to image location of hydrogen atom in body

distinguishes body tissues based on water content, structures with low water content not very visible

gives high contrast images of soft tissue even if blocked by bone

function:
imaging of brain, spinal cord and nerve to detect abnormalities (i.e tumor)
assess joints, ligaments, cartilage and other soft tissue
fMRI ; tracks blood flow in different brain regions and shows brain activity

cons:
more expensive
slower than CT
cannot be used for patients with metal implants

Ultrasound Imaging (mechanism, function, characteristic of image, pros, cons)

uses high frequency sound waves (ultrasound) which reflects body tissues

function:
detect artherosclerosis and heart valve disorders
monitor fetus during pregnancy
diagnosing abdominal or pelvic disorder (gallbladder disease)

pros:
inexpensive
easy to use
no x-ray, safe to observe fetus
monitor movement in real time

cons:
low resolution image