Living things consists of several levels of structural organization that are associated with one another in various ways.
CHEMICAL LEVEL It is the lowest level of organization It includes atoms and molecules that are essential in maintaining life.
CHEMICAL LEVEL Atom A unit of matter that comprises a chemical element. It is the smallest particle of an element.
CHEMICAL LEVEL Atom Elements essential for maintaining life are: Carbon (C) Hydrogen (H) Oxygen (O) Nitrogen (N) Calcium (Ca) Potassium (K) and Sodium (Na)
CHEMICAL LEVEL Molecule The chemical combination of two or more atoms.
CHEMICAL LEVEL Molecule Carbohydrates – includes sugars, starches, glycogen and cellulose Plants store carbohydrates as starch and use the carbohydrates cellulose to build the cell wall In animals, it provide a readily available source of energy to drive metabolic reactions Fats – also provides energy and forms adepose tissue Proteins – for muscle growth and repairs Vitamins and minerals – catalyzes metabolic reactions
CELLULAR LEVEL The next higher level of organization. It yields from the combinations of molecules from the chemical level. CELL: Is the basic structural and funcional unit of an organism. There are several kinds of cell in our body, and each has a different stuctures and each performs a different function. Each cell contain specialized structures called organelles that perform specific functions.
TISSUE LEVEL It is the level in which different cell types cells are joined together to form a structure called, tissue. Tissues – are group of similar cells (and the substance surrounding them) that usually arise from common ancestor cells and work together to perform a particular function. The four basic types of tissue in the body are: Epithelial tissue Muscle tissue Connective tissue Nervous tissue
ORGAN LEVEL It is where different kinds of tissues are joined to form a structure of a body called organ. Organs – are structures that are composed of two or more different tissues, have specific functions, and usually have recognizable shapes. Some examples of organs are the heart, liver, lungs, brain and stomach.
SYSTEM LEVEL The level where different organs are joined together to form a body system. Consists of several related organs that have a common function.
SYSTEM LEVEL 11 systems in the human body Integumentary System – helps regulate body temperature, protects the body, eliminates some wastes, helps produce vitamin D, and receives certain stimuli such as temperature, pressure, and pain. Includes skin, hair, nail, sweat and oil glands. Skeletal System – supports and protects the body, assist in body movements, houses cells that give rise to blood cells, and store minerals. Includes all bones of the body, cartillages and joints. Muscular System – participates in bringing about movement, produces heat, maintains posture and gives shapes to the body. Specifically refers to skeletal muscle tissue.
SYSTEM LEVEL 11 systems in the human body Nervous System – regulates body activities through action potentials (nerve impulses) by detecting changes in the internal and external environment, interpreting the changes, and responding to the changes by inducing muscular contractions or glandular secretions. Includes brain, spinal chord, nerves and special sense organs such as the eyes and ears. Endocrine System – regulates body activities through hormones, chemicals transported in the blood to various target organs of the body. Includes all hormone-producing glands and cells such as the pituitary gland, thyroid gland, and pancreas. Circulatory System - carries carbon dioxide and wastes away from cells, helps maintain the acid-base balance of the body, protects against disease, prevents hemorrhage by forming blood clots, and helps regulate body temperature. Includes blood, heart and blood vessels.
SYSTEM LEVEL 11 systems in the human body Lymphatic and Immune System – returns proteins and plasma to the cardiovascular system, transports fats from the gastrointestinal tracts to the cardiovascular system, filters body fluid, site of maturation and proliferation of certain white blood cells, and helps protect against disease through the production of proteins called antibodies, as well as other responses. Includes lymph, lymphatic vessels, and structures or organs ontaining lymphatic tissue (large numbers of white blood cells called lymphocytes), such as the spleen, thymus gland, lymph nodes and tonsils. Respiratory System – supplies oxygen, eliminates carbon dioxide, helps regulate the acid-base balance of the body, and produces vocal sounds (phonation). Includes lungs and series of associated passageways leading into and out of them. Digestive System – performs the physical and chemical breakdown and absorption of food for use by cells and eliminates solid and other wastes. Includes the gastrointestinal tract, salivary galnds, liver, gallbladder, and pancreas.
SYSTEM LEVEL 11 systems in the human body Urinary System – regulates the volume and chemical composition of blood, eliminates wastes, regulates fluid and electrolyte balance, helps maintain the acid-base and calcium balance of the body, and helps regulate red blood cell production. Includes the kidney, ureters, urinary bladder, and urethra that together produce, store, and eliminate urine. Reproductive System – reproduces the organism for continuity. Includes the gonads that produce reproductive cells or gametes, uterine (Fallopian) tubes and uterus in females, the epididymis, ductus (Vas) deferens, and penis in males that transport and store reproductive cells.
11 Systems of the Human Body Integumentary System Skeletal System Muscular System Nervous System Endocrine System Circulatory System Lymphatic / Immune System Respiratory System Digestive System Urinary System Reproductive System
ORGANISMIC LEVEL The highest level of organizational structure where all parts of the body are functioning with one another to comprise the total organism – one living individual.
LEVELS OF STRUCTURAL ORGANIZATION Chemical Level Cellular Level Tissue Level Organ Level System Level Organismic Level