Anatomical Position
Definition:
The anatomical position is the standard position of the body used by anatomists and health professionals to describe the location of body parts correctly.
Features of Anatomical Position
In anatomical position, the body is:
Standing upright
Head and eyes facing forward
Arms by the sides of the body
Palms facing forward
Thumbs pointing outward
Feet together or slightly apart
Toes pointing forward
2. Anatomical Terms (Terms of Position & Direction)
These terms describe the location of one body part in relation to another.
1. Superior (Cranial)
Means: Above
Example: The head is superior to the neck.
2. Inferior (Caudal)
Means: Below
Example: The stomach is inferior to the heart.
3. Anterior (Ventral)
Means: Front
Example: The chest is anterior to the spine.
4. Posterior (Dorsal)
Means: Back
Example: The vertebral column is posterior to the sternum.
5. Medial
Means: Nearer to the midline
Example: The nose is medial to the eyes.
6. Lateral
Means: Away from the midline
Example: The ears are lateral to the nose.
7. Proximal
Means: Nearer to the point of origin or trunk
Example: The shoulder is proximal to the elbow.
8. Distal
Means: Farther from the point of origin
Example: The fingers are distal to the wrist.
9. Superficial
Means: Near the surface
Example: The skin is superficial to the muscles.
10. Deep
Means: Away from the surface
Example: Bones are deep to muscles.
11. Central
Means: Near the center
Example: The brain is part of the central nervous system.
12. Peripheral
Means: Away from the center
Example: Spinal nerves are peripheral nerves.
13. Ipsilateral
Means: Same side of the body
Example: Right arm and right leg are ipsilateral.
14. Contralateral
Means: Opposite side of the body
Example: Right arm and left leg are contralateral.
3. Anatomical Terms of Movement (Brief)
Flexion: Bending a joint
Extension: Straightening a joint
Abduction: Movement away from midline
Adduction: Movement toward midline
Rotation: Turning around an axis
Circumduction: Circular movement
Pronation: Palm facing downward
Supination: Palm facing upward
Anatomical Planes (in Simple Words)
Anatomical planes are imaginary flat lines that divide the body into parts.
They help doctors, nurses, and students describe the location of organs and movements clearly.
1. Median / Midsagittal Plane
Definition:
An imaginary vertical plane that divides the body into two equal right and left halves.
Key point:
Passes exactly through the midline of the body
Example:
Divides the body into equal right and left sides
Used to compare right and left organs
Exam tip: Only one median plane exists.
2. Sagittal / Paramedian Plane
Sagittal Plane
Definition:
An imaginary vertical plane that divides the body into right and left parts, but not equal.
Paramedian Plane
A sagittal plane that runs parallel to the median plane
Divides the body into unequal right and left halves
Example:
Dividing the body to show only the right lung or left kidney
Exam tip:
Median = equal
Sagittal/paramedian = unequal
3. Coronal Plane (Frontal Plane)
Definition:
An imaginary vertical plane that divides the body into anterior (front) and posterior (back) parts.
Example:
Chest is anterior, spine is posterior
Clinical use:
X-ray of chest
Studying organs from front and back view
4. Horizontal Plane
Definition:
An imaginary plane that divides the body into upper (superior) and lower (inferior) parts.
Also called:
Transverse plane
Example:
Separates chest (upper) from abdomen (lower)
5. Transverse Plane
Definition:
An imaginary plane that cuts the body at right angles to the long axis, dividing it into upper and lower parts.
Same as horizontal plane
Example:
CT scan images are usually taken in transverse plane
6. Oblique Plane
Definition:
An imaginary plane that cuts the body at an angle, not vertical and not horizontal.
Example:
Oblique cut of heart or liver
Used when organs are placed diagonally
Clinical use:
MRI and special imaging views
Terms Related to Body Movement (Simple Explanation)
Body movements occur at joints when muscles contract. These terms help us describe how a body part moves.
1. Flexion
Meaning: Bending a joint; decreasing the angle between two bones
Example:
Bending the elbow
Bending the knee
2. Extension
Meaning: Straightening a joint; increasing the angle between bones
Example:
Straightening the elbow
Straightening the knee
3. Abduction
Meaning: Movement away from the midline of the body
Example:
Raising the arm sideways
Moving leg away from body
4 Adduction
Meaning: Movement toward the midline of the body
Example:
Bringing arm back to side
Bringing legs together
5. Rotation
Meaning: Turning a body part around its own long axis
Example:
Turning head right or left
Rotation of shoulder or hip
Types:
Medial (Internal) Rotation: Turning inward
Lateral (External) Rotation: Turning outward
6. Circumduction
Meaning: Circular movement combining flexion, extension, abduction, and adduction
Example:
Moving arm in a circle at shoulder joint
7. Pronation
Meaning: Turning palm downward or backward
Example:
Palm facing down on table
9. Supination
Meaning: Turning palm upward or forward
10. Dorsiflexion
Meaning: Bending foot upward at ankle
Example:
Toes pointing toward the leg
11. Planter Flexion
Meaning: Bending foot downward
Example:
Standing on toes
12. Inversion
Meaning: Turning sole of foot inward
Example:
Twisting ankle inward
13. Eversion
Meaning: Turning sole of foot outward
Example:
Twisting ankle outward
Basic Life Processes (Simple Explanation)
Basic life processes are the activities that keep the body alive and healthy.
Important life processes include nutrition, respiration, transportation, and regulation (endocrine system).
1. Nutrition
Meaning:
Nutrition is the process by which the body takes in food and uses it for energy, growth, repair, and maintenance.
Steps of Nutrition
Ingestion – Taking food into the mouth
Digestion – Breaking food into simple substances
Absorption – Nutrients enter the blood from intestine
Assimilation – Cells use nutrients for energy and growth
Egestion – Removal of undigested food
Importance of Nutrition
Provides energy
Helps in growth and repair
Maintains body resistance
2. Transportation
Meaning:
Transportation is the process of carrying materials like oxygen, nutrients, hormones, and waste products from one part of the body to another.
Transport System in Humans
Heart – Pumps blood
Blood – Carries substances
Blood vessels – Arteries, veins, capillaries
What is Transported?
Oxygen and carbon dioxide
Digested food
Hormones
Waste products
Importance
Supplies oxygen and nutrients to cells
Removes waste materials
3. Respiratory System (Respiration)
Meaning:
Respiration is the process of taking in oxygen and giving out carbon dioxide.
Types of Respiration
External respiration – Breathing (lungs)
Internal respiration – Oxygen used by cells to release energy
Main Organs
Nose
Trachea
Lungs
Alveoli
Importance
Provides oxygen for energy production
Removes carbon dioxide
Helps maintain acid–base balance
4. Endocrine System
Meaning:
The endocrine system is a system of glands that release hormones directly into the blood to control body activities.
What are Hormones?
Chemical messengers
Control growth, metabolism, reproduction, and emotions
Major Endocrine Glands
Pituitary – Master gland
Thyroid – Controls metabolism
Adrenal – Stress response
Pancreas – Controls blood sugar
Gonads – Reproduction
Importance
Regulates growth and development
Maintains internal balance (homeostasis)
Controls puberty and stress
Elimination of Waste Products (Simple Explanation)
Elimination of waste means removing unwanted and harmful substances from the body.
This is very important to keep the body healthy and balanced.
1. Elimination of Carbon Dioxide
What is it?
Carbon dioxide (CO₂) is a waste gas produced during respiration (energy production) in body cells.
How is it removed?
Carbon dioxide is carried by blood to the lungs
It is removed from the body during exhalation (breathing out)
Organ involved
Lungs
Importance
Prevents acid buildup in blood
Maintains normal breathing and blood pH
2. Elimination of Urine
What is urine?
Urine is a liquid waste containing:
Urea
Excess water
Salts
Toxins
How is urine formed and removed?
Kidneys filter blood and form urine
Urine passes through:
Ureters → Urinary bladder → Urethra
Finally, urine is excreted outside the body
Importance
Removes toxic substances
Maintains water and electrolyte balance
Controls blood pressure
3. Elimination of Feces
What is feces?
Feces are solid waste formed from:
Undigested food
Bacteria
Dead cells
How is it removed?
Undigested food moves to large intestine
Water is absorbed
Waste is stored in rectum
Feces are expelled through anus (defecation)
Importance
Removes undigested material
Prevents toxin accumulation
Below is a brief, simple, exam-oriented explanation of systems of the human body with their main functions, written in easy language for nursing and medical students.
Systems of the Human Body (Brief & Simple)
1. Integumentary System
Organs: Skin, hair, nails, sweat glands
Functions:
Protects the body from injury and germs
Regulates body temperature
Prevents water loss
Helps in sensation (touch, pain, heat)
2. Skeletal System
Organs: Bones, joints, cartilage, ligaments
Functions:
Gives shape and support to the body
Protects vital organs (brain, heart, lungs)
Helps in movement with muscles
Produces blood cells
Stores calcium and minerals
3. Muscular System
Organs: Muscles (skeletal, smooth, cardiac)
Functions:
Helps in body movement
Maintains posture
Produces heat
Helps in movement of food and blood
4. Nervous System
Organs: Brain, spinal cord, nerves
Functions:
Controls and coordinates body activities
Receives and responds to stimuli
Helps in thinking, memory, and emotions
Controls voluntary and involuntary actions
5. Endocrine System
Organs: Pituitary, thyroid, adrenal glands, pancreas, gonads
Functions:
Produces hormones
Controls growth and development
Regulates metabolism and stress
Maintains internal balance (homeostasis)
6. Cardiovascular System
Organs: Heart, blood, blood vessels
Functions:
Transports oxygen and nutrients
Removes waste products
Carries hormones
Helps in temperature regulation
7. Lymphatic System
Organs: Lymph nodes, lymph vessels, spleen, tonsils
Functions:
Protects the body from infection
Drains excess tissue fluid
Absorbs fats from intestine
Supports immune system
8. Respiratory System
Organs: Nose, trachea, lungs, alveoli
Functions:
Supplies oxygen to the body
Removes carbon dioxide
Helps in speech
Maintains acid-base balance
9. Digestive System
Organs: Mouth, esophagus, stomach, intestines, liver, pancreas
Functions:
Digests food
Absorbs nutrients
Provides energy
Eliminates solid waste (feces)
10. Urinary System
Organs: Kidneys, ureters, bladder, urethra
Functions:
Removes waste products as urine
Maintains water and salt balance
Regulates blood pressure
Maintains acid-base balance
11. Reproductive System
Male Organs: Testes, penis, prostate
Female Organs: Ovaries, uterus, fallopian tubes, vagina
Functions:
Produces sex cells (sperm and ova)
Helps in reproduction
Produces sex hormones
Female system supports pregnancy and childbirth
Very Short Summary (One-Line Functions)
Skin → Protection
Bones → Support and movement
Muscles → Movement
Nerves → Control and coordination
Hormones → Regulation
Heart & blood → Transport
Lymph → Immunity
Lungs → Breathing
Digestive organs → Nutrition
Kidneys → Excretion
Reproductive organs → Reproduction