Human Body Systems Body systems work together and depend on one another Subtitle

How Is the Body Organized? Cells Tissues Organs Organ Systems

Cells The smallest unit of life Individual cells in multicellular organisms tend to be specialized. Specialized cells are uniquely suited to perform a particular function. Bone Cell Blood Cell Nerve Cell

Tissues Come together to make A group of cells that work together to perform a specific function in the body ex: many muscle cells join to make up muscle tissue Come together to make Muscle cells

Organ Two or more tissues working together to perform a specific job. Ex: brain, stomach, intestine, heart, lungs, skin, ears In order for the heart to work, blood tissue, muscle tissue, and nerve tissues work together.

Organ System Skin/Integumentary Cardiovascular/Circulatory Muscular Different organs working together to perform a particular job make up an organ system there are 11 organ systems in the human body: Skin/Integumentary Cardiovascular/Circulatory Muscular Skeletal Nervous Respiratory Digestive Urinary Reproductive Lymphatic/Immune Endocrine (hormones) bones + cartilage + ligaments + joints = Skeletal System

Skin, nails, & hair Integumentary System The largest organ of the human body. Skin covers the body & prevents water loss Protects against injuries & infections

Muscular System There are about 600 muscles in the body. Muscles work with bones for movement. Muscles work by contracting and relaxing. Body has three types of muscles: Skeletal muscle Smooth muscle Cardiac muscle

Skeletal System The skeletal system Provides shape and support Allows the body to move Protects the internal organs Produces blood cells

Cardiovascular System The cardiovascular system Consists of heart, blood vessels, & blood Carries nutrients and oxygen to cells Removes waste from the cells

Respiratory System The respiratory system Moves oxygen from outside into the body Removes carbon dioxide from the body Nose, pharynx, trachea, and bronchi are all organs of respiratory system

Digestive system The digestive system Breaks down food into nutrients (digestion) Absorbs nutrients into blood stream (absorption) Eliminates waste from the body Starts at the mouth and ends at anus

Urinary System The urinary system Collects liquid waste produced by the cells Removes the waste from the body (excretion) Filtering waste produces urine. The two kidneys, ureters, urinary bladder, and urethra, are the organs of urinary system. Kidney Ureter Bladder

Nervous System The nervous system Consists of the brain, spinal cord, and neurons Receives information about inside & outside of the body Responds to the received information Helps maintain homeostasis

Immune System Immune system defends the body against pathogens (bacteria & viruses) The cells of the immune system recognize the different kind of pathogen and destroy them.

Endocrine System The endocrine system controls the body’s daily activities Controls growth and development Produces chemicals named hormones Hormones tell order organs what to do

Reproductive System The male and female reproductive system produce sex cells and sex hormones. Female reproductive system nourishes the developing fetus and gives birth.