Body Systems

Nervous System Organs Brain Interprets and translates information from nerve impulses Three Parts of the Brain: Cerebrum – main part of the brain; controls thinking, hearing, etc. Cerebellum – At back of the head; controls muscles and balance Medulla – Connects brain to spinal cord; controls involuntary actions such as breathing

Nervous System Organs Spinal Cord Messages are sent to the brain through the spinal cord Exception are reflexes that skip the brain and go straight to the spinal cord Nerves Carry messages throughout the body

Nervous System Functions First messenger system Sends messages as electrical impulses

Nervous System (Central and Peripheral) Central Nervous System (CNS) Brain and Spinal Cord Regulates VITAL functions Heart rate Breathing Hormone Release Peripheral Nervous System (PNS) Carries information toward the central nervous system Sends impulses away from CNS

Circulatory System Organs Heart Pumps Blood Blood RBC, WBC, platelets, plasma Hemoglobin – iron rich protein that carries oxygen Blood Vessels Arteries – carry oxygen RICH blood AWAY from the heart Veins – carry oxygen POOR blood INTO the heart Capillaries – connect arteries and veins

Circulatory System Function Transport system Arteries: Moves oxygen to the cells Veins: Carries carbon dioxide away from the cells

Digestive System Organs Mouth The enzyme AMYLASE breaks down carbohydrates into simple sugars Esophagus – muscular tube Stomach PEPSIN is an enzyme that breaks down proteins Digested food is called chime Small Intestine Chime is absorbed into the bloodstream Large Intestine Removes water from chime Rectum Solid food travels out of the body

Digestive System Functions Chemically and physically breaks down food Converts food into essential nutrients that are absorbed into the bloodstream Nutrients are absorbed in small intestine

Respiratory System Organs Nose Trachea – “Windpipe” Larynx - Voice box Lungs Aveoli Site of gas exchange (inflatable sacs) Bronchi Two large passageways leading to lungs Diaphragm The muscle under the lungs. It contracts and relaxes to move gases in and out of lungs

Respiratory System Functions Respire = to breathe Gas exchange Delivering oxygen to the body (inhale) and removing carbon dioxide from the body (exhale) Gases are carried within the blood (Circulatory System)

Endocrine System Organs Pituitary gland Produces growth hormones Thyroid gland produces hormone thyroxin to regulate metabolism Adrenal gland Produces adrenaline for fight or flight Testes Produces testosterone used in sperm production and male traits Ovaries Produces estrogen used in egg production and female traits Pancreas Produces insulin to regulate sugar in bloodstream

Endocrine System Functions Glands release hormones into the bloodstream to control body functions Second messenger system of the body (SLOW)

Integumentary Organs Organs Skin – largest organ Sweat glands Nails Hair

Integumentary Function Acts as a barrier between you and the outside world. Regulates body temperature and removes wastes through sweat

Skeletal System Organs Bones Joints Connect bone to bone by ligaments Ligaments are tough bands of tissue that hold bones together Tendons Connect bone to muscle

Skeletal System Functions Bones are the framework for the body providing its shape Protection for internal organs Blood cell production Made in red bone marrow Stores calcium and phosphorous

Muscular System Organs Skeletal muscle Attached to the bone by tendons Smooth muscle Stomach, Intestine, Uterus Cardiac muscle Only in the heart

Muscular System Functions Enable the body to move Voluntary muscles Muscles you can control Arms, legs, hands, and face Involuntary muscles Muscles you can’t control They move automatically Cardiac muscles, stomach, intestines

Immune/Lymphatic Organs White Blood Cells (WBC) Spleen Filter blood Lymph Nodes Filter lymph from dead cells, antigens before returning it to the blood stream Thymus Near heart Where T cells learn their jobs Lymph Fluid that leaked out of cells Lymphatic Vessels Collect lymph and return it to the bloodstream Bone Marrow B cell production

Immune/Lymphatic Functions Fight off diseases caused by pathogens First Line of Defense Skin Saliva in mouth Hair and mucus in breathing passages Stomach acid – traps and kills most pathogens Second Line of Defense (Widespread) Inflammatory response WBC fighting infection (antigens) Third Line of Defense (Specific) Immune response WBC, T cells, and lymphocytes recognize a virus and activate B-Cells

Reproductive Organs Male: Penis Places sperm inside the female body Ovary produces eggs = female gamete Produces estrogen Utereus Holds the embryo, fetus, baby Fallopian Tubes Catches the egg from the ovary and transports it to the uterus Vagina Allow entry of sperm and exit of baby at birth Male: Penis Places sperm inside the female body Testis Produces sperm = male gamete Produces testosterone

Reproductive Functions To ensure the survival of the species To reproduce gametes = sex cells To nurture the developing offspring

Excretory System Organs Kidneys Filters waste from blood Ureters Tubes that lead from each kidney to bladder Bladder Muscular organ that holds urine Urethra Tube that carries urine from the bladder out of the body

Excretory System Function Excrete = to get rid of = REMOVE Maintains homeostasis by: Cleansing blood of LIQUID wastes such as urine and sweat Controls blood volume by removing extra fluid