Mod 1 Flashcards
Human Anatomy
study of structure(morphology)
Gross Anatomy
deals with tissues bigger than 0.1 mm.
Microscopic Anatomy(Histology)
deals with smaller structures.
Tissues, organs etc
may use light or electron microscopy
Systemic Anatomy
Skeletal. muscular, nervous, cardiovascular, digestive, respitory
Regional Anatomy
- Back and lower limbs
- Upper limb and thorax
- Abdomen and pelvis
- Head and neck
Surface Anatomy
shapes and markings on body surface
Developmental Anatomy
deals with structural changes in the body throughout life
Embryology
studying development of the body before birth
Pathologic Anatomy
deals with structural changes in the tissues caused by a disease
Functional Anatomy
deals with function of the body structures
Anatomical Position
Standing still and palms facing forward
Principal Axes
longitudinal(vertical) axes
Transverse(horizontal) axes
Saggital axes
Principle planes
- median(median sagittal/midsaggittal) plane
- Sagittal(paramedian/parasaggital) plane
- Frontal(coronal) plane
- Transverse plane
Cranial
toward the head
superior
upward with the body erect
caudal
toward the buttocks
rostral
toward the mouth
inferior
downward with the body erect
medial
toward the middle
lateral
away from the middle
medius
in the middle
median
within the median plane
central
toward the center of the body
peripheral
toward surface of the body
anterior
toward the front
ventral
toward the abdomen
posterior
toward the back
dorsal
toward the back
proximal
toward the limb attachment
distal
away from the limb attachment
Flexion
bending
extension
stretching
abduction
away from the body
adduction
toward the body
rotation
pivoting or rotary motion
curcumduction
circular movement
Vertebral Column
forms basic structure of the trunk.
of vertebrae and intervertebral disks
33-34 vertebrae and intervertebral disks.
7 cervical 12 thoracic 5 lumbar 5 sacral 4-5 coccygeal
Intervertebral disks and function
fibrocartilaginous structures between vertebrae.
Absorb shock, assure no friction between bones, facilitate the movements of the body.
Contents of the vertebral canal
spinal cord and its blood vessels plus the meninges and cerebro-spinal fluid
Myelography
using contrast medium around the spinal cord(subarachnoid space)
Barium swallow
drinking Barium sulfate contrast medium to study the internal covering layer(mucous membrane) of the digestive tract
Computed Tomography(CT scan)
Used for detection of intracranial lesions or anatomy/pathology of other parts of the body.
The procedure is quick, safe and accurate.
The physics here is like the X-ray.
The X-ray tube emits a narrow beam
scanning the body through an arc of 180
degree around patients body.
The X-ray having passed through the body
are collected by a special x-ray detectors
and fed to a computer which is then
reconstructed and displayed on a TV
like screen.
Enhancement of the contrast between
tissues (due to different blood flow) can
be achieved by IV injection of contrast
(iodine-containing) medium.
Magnetic Resonance imaging (MRI):
This method subjects the body to strong
magnetic field (60000 times stronger
than that of the earth) and radio waves.
The patient lies in a chamber and his/her
body is surrounded by a huge magnet.
When magnet is turned on, the nuclei
of body’s hydrogen atoms line up parallel
to the strong magnetic field.
The patient is then exposed to a brief
pulse of radio waves (below the FM radio-
frequency), which knocks the spinning
protons out of alignment.
When the radio waves are turned off, the
protons return to their alignment in the
magnetic field, which emit their own faint
radio waves. Sensors detect these waves,
and computer translates them into images.
MRI is absolutely safe and better
differentiates between the white and gray
matter than the CT (gray matter contains
more water).
In addition, hydrogen atoms are less bound
in the fat.
Positron Emission Tomography (PET):
Produces images by detecting radioactive isotopes
Injected into the body.
Advantage of PET is that its images contain messages
about chemical, physiological and pharmacological
processes in the body. An appropriate isotope is
incorporated into molecules of known biochemical
behavior in the body and then injected into the patient.
The metabolic activity of the compound can be studied
by its decay, and emission of positively charged
electrons (positrons), which indirectly lead to production
of gamma rays. Sensor within a scanner pick up the
emitted gamma rays, which are then translated into
electrical impulses and sent to a computer.
A picture of the isotope’s location can be seen
on the screen by colors.
PET is used to assess functional blood flow to the brain
and heart. By mapping increases in blood flow, it can
determine which part of brain are most active during
speech, seeing, comprehension, etc.
PET resolution is low, images take a long time
to form, It cannot record fast changes in the
brain activity; an expensive Cyclotron machine
is needed on the site to make the isotope, and for
these reasons, PET is gradually being replaced
by other techniques such as fMRI which measures blood
oxygen in specific areas of brain during various activities.
Bone Classification
- long bones
- short bones
- flat bones
- irregular bones
Long bones
longer than wide
have a shaft(diaphysis) plus 2 ends called epiphysis
Short bones
roughly cube-shaped
Flat bones
thin and flattened
usually curved
Irregular bones
various shapes
do not fit long, short, or flat categories
Functions of the bones
- Support - framework to protect organs
- Movement - skeletal muscles use bones as levers
- Mineral storage - reservoir for important minerals
- Blood-cell formation - contains red marrow
Gross Anatomy of the bone
- compact bone - dense outer layer of bone
2. spongy(cancellous) bone - internal network of bone
Long bone components
- Diaphysis - shaft of a bone
- Epiphysis - ends of a bone
- Blood vessels - well vascularized
- Medullary Cavity - hollow cavity - filled with marrow
- Membranes - periosteum, Sharpey’s fibers, and endosteum
Bone design and stress
anatomy of a bone reflect stresses.
compression and tension greatest at external surfaces
Ossification and development of the bone
- Intramembranous ossification
2. Endochondral Ossification
Intramembranous ossification
Bones are directly ossified without any pre-existing cartilage.
Skull bones and the clavicle are formed directly from mesenchyme.
Endochondral ossification
Bones develop from a pre-existing cartilage.
Most of the other bones develop initially from hyaline cartilage.
Endochondral ossification steps
1- Formation of bone collar around hyaline cartilage model
2- Cavitation of the hyaline cartilage
3- invasion of the cavities by the periosteal bud and spongy bone formation
4- Formation of the medullary cavities and secondary ossification centers
5- Ossification of the epiphysis (hyaline cartilage remains in epiphysial plate
and articular cartilages (surfaces).
Ossification at the epiphysial plate
In epiphyseal plates of growing bones cartilage is organized for quick growth. Cartilage cells form tall stacks.
Chondroblasts at the top of stacks divide quickly and pushes the epiphysis
away from the diaphysis.
This lengthens the long bone
During childhood and adolescence:
Bones lengthen entirely by growth of the epiphyseal plates.
Cartilage is replaced with bone tissue as quickly as it grows
As adolescence draws to an end:
cartilage stops growing and is replaced by bone
tissue, diaphysis and epiphysis fuse.
Hormonal regulation of bone growth
Growth hormone: produced by the pituitary gland, stimulates epiphyseal plates
Thyroid hormone: ensures that the skeleton retains proper proportions
Sex hormones: Promote bone growth, later induce closure of epiphyseal plates
Osteoporosis
characterized by low bone mass, bone reabsorption outpaces
bone deposition, occurs in most of women after menopause (secretion
of estrogens helps maintain bone density).
Osteomalacia
occurs in adults, bones are inadequately mineralized
Rickets
occurs in children, analogous to osteomalacia, weakened and bowed
legs, malformation of the head and ribs (caused by dietary Vit D and calcium
phosphate deficiency).
Paget’s disease
characterized by excessive rate of bone deposition but reduced
mineralization leading to bone thickening.
Achondroplasia
congenital (genetic disease), defective cartilage growth and
defective enchondral ossification leading to Dwarfism.
Osteosarcoma
a form of bone cancer
Muscle
Makes up nearly half the body’s mass
The main tissue in the heart and walls of hollow organs
Functions of muscle tissue
1- Movement
Skeletal muscle: attached to skeleton, moves body by moving the bones
Maintenance of posture: enables the body to remain sitting or standing
Smooth muscle: squeezes fluids and other substances through hollow organs
2- Joint stabilization
3- Heat generation: contractions produce heat, keeps normal body temperature
Types of muscles
1- Skeletal muscle tissue
2- Cardiac muscle tissue
3- Smooth muscle tissue
Skeletal muscle tissue
packaged into skeletal muscles
Makes up 40% of body weight. Cells are striated
Cardiac muscle tissue
occurs only in the walls of the heart
Smooth muscle tissue
in the walls of hollow organs.
Cells lack striations
