Human Body Systems
SubtitleBody systems work together and depend on one another
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.
Nerve CellBlood CellBone Cell
Tissues
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
M u s c l e c e l l s
Come together to make
Organ Two or more tissues working together to perform a specific job. Ex: brain, stomach, intestine, heart, lungs, skin, earsIn order for the heart to work, blood tissue, muscle tissue, and nerve tissues work together.
Organ SystemDifferent organs working together to perform a particular job make up an organ system
there are 11 organ systems in the human body:
Skin/IntegumentaryCardiovascular/CirculatoryMuscularSkeletalNervousRespiratoryDigestiveUrinaryReproductiveLymphatic/ImmuneEndocrine (hormones)
bones + cartilage + ligaments +
joints= Skeletal
System
Integumentary System
• Skin, nails, & hair –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 SystemThe cardiovascular system • Consists of heart, blood vessels, &
blood• Carries nutrients and oxygen to cells• Removes waste from the cells
Respiratory SystemThe respiratory system• Moves oxygen from outside into the
body• Removes carbon dioxide from the
body• Nose, pharynx, trachea, bronchi, and
lungs 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 SystemThe 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
Human body temp:37 C (98.6 F)
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 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.