Systems of the human body

Systems of the human body

There are eleven systems of the human body as described below:

1.       INTEGUMENTARY SYSTEM :

Components : skin and its structures (e.g., hair,nails,sweat glands,and oil glands).

Functions :

·         Protects the body

·         Helps regulate body temperature

·         Eliminates some wastes,

·         Helps make vitamin D

·         Detects sensations (e.g., touch , pain, warmth,and cold).

2.       SKELETAL SYSTEM

Components : bones , joints and their associated cartilages.

             Functions:

·         Supports and protects the body

·         Provides a surface area for muscle attachments

·         Helps body movements

·         Houses cells that produce blood cells

·         Stores minerals and lipids (fats)

3.       MUSCULAR  SYSTEM

Components : muscles (skeletal muscle tissue, usually attached to bones).

·         Produces body movements (e.g., walking).

·         Stabilizes body position (posture)

·         Generates heat.

4.       NERVOUS SYSTEM

Components : brain , spinal cord, nerves and special sense organs (e.g., eyes and ears).

·         Generates nerve impulses (action potentials) to regulate body activities.

·         Detects changes in the body’s internal and external environment.

·         Interprets the changes and responds by causing muscular contractions or glandular secretions.

5.       CARDIOVASCULAR  SYSTEM

Components : blood , heart, and blood vessels.

                Functions :

·         Heart pumps blood through blood vessels

·         Blood carries oxygen and nutrients to cells and carbon dioxide and wastes away from cells; helps regulate acid-base balance, temperature,and water content of body fluids.

·         Blood components help defend against disease and repair damaged blood vessels.

6.       ENDOCRINE SYSTEM

Components : hormone producing glands (pineal gland, hypothalamus,pituitary gland, parathyroid glands,thymus,adrenal glands,pancreas,ovaries,and testes), and hormone producing cells in several other organs.

Functions: secrete hormones (chemical messengers) in blood that regulate body activities in target organs.

7.       LYMPHATIC SYSTEM AND IMMUNITY

Components : lymphatic fluid and vessels; also includes spleen,thymus,lymph nodes and tonsils.

Functions :

·         Returns proteins and fluid to blood

·         Carries lipids from gastrointestinal (GI) tract to blood

·         Protects against disease causing microbes .

8.       RESPIRATORY SYSTEM

Components : lungs,pharynx (throat), larynx (voice box), trachea (wind pipe), and bronchial tubes leading into lungs.

Functions :

·         Transfers oxygen from inhaled air to blood and carbon dioxide from blood to exhaled air.

·         Helps regulate acid-base balance of body fluids.

·         Helps to produce sounds when air flows out through vocal cords.

9.       DIGESTIVE SYSTEM

Components : mouth,pharynx,oesophagus,stomach,small and large intestines,anus; and accessary organs such as the salivary glands,liver, gallbladder,and pancreas.

Functions :

·         Achives physical and chemical breakdown of food.

·         Absorbs nutrients.

·         Eliminates solid wastes.

10.   URINARY SYSTEM :

Components : kidneys ,ureters, urinary bladder, and urethra.

Functions

·         Produces, stores and eliminates urine

·         Eliminates wastes and regulates volume and chemical composition of blood

·         Helps maintain the acid base balance of body fluids

·         Maintain body’s mineral balance

·         Helps regulate production of red blood cells

11.   REPRODUCTIVE SYSTEM :

Components : gonads (testes in male and ovaries in female) and associated organs eg. Uterine tubes , uterus and vagina in females and epididymis, vas deferens and penis in males

Functions :

·         Gonads produce gamets (sperm or oocytes) that unit to form a new organism

·         Gonads release hormones that regulate reproduction and other body processes

·         Associated organs transport and store gametes

                                BASIC LIFE PROCESSES

The six important life processes of human body are

1.       Metabolism : it is the sum of the chemical processes that occur in the body and are of two types

·         Catabolism : is the breakdown of complex chemical substances into simpler components eg. Digestion of proteins into amino acids

·         Anabolism : Is the building up of complex chemical substances from smaller , simpler components eg. Use of amino acids to build new proteins of the body.

2.       Responsiveness : it is the body’s ability to detect and respond to changes eg. Withdrawing of hand when pricked by needle. Never cells respond by generating electrical signals called nerve impulses.  Muscles respond by contracting

3.       Movements : it includes motion of the whole body , individual organs , single cell movement and even subcellular structures like cytoplasm

4.       Growth : it is  an increase in body size and weight eg. Increase in size and number of cells

5.       Differentiation : it is the development of a cell from an unspecialized to a specialized state eg. Stem cell in red bone marrow

6.       Reproduction : it refers either to the formation of new cells or to the production of a new cell or to the production of a new individual from zygote after fertilization of an ovum by a sperm cell.

Cells ,tissues and organisms die when life processesncease to be occur.