Body Systems Notes Nervous, Integumentary, Immune/Lymphatic, Circulatory, Skeletal, Respiratory, Digestive, Excretory, Endocrine, Reproductive
Homeostasis: maintaining a balance. Examples: temperature, insulin levels, nutrients, etc.
Nervous System Recognizes and coordinates the body s response to changes in its internal and external environments
Main Parts of Nervous System Brain Spinal Cord Nerves
Nervous System Random Facts Neurons have myelin on them which is like insulation A nerve impulse is an all or nothing response (must reach the threshold Somatic vs. Autonomic nervous system Fight or Flight response Optic Nerve is your blind spot
Integumentary System Guards against infection and injury and uv radiation from the sun Helps regulate body temperature
Main Parts of Integumentary System Skin Hair Nails Oil Glands Sweat Glands
Integumentary System Random Facts Can be considered part of the excretory system Vitamin D is produced using sunlight Once every four to six weeks, a new layer of dead cells replaces an older layer Melanocytes of people with darker skin produce more melanin than people with lighter skin When the body needs to conserve heat on a cold day, the blood vessels in the dermis narrow Acne develops when sebum and dead skin cells form plugs in hair follicles (bacteria get trapped inside)
Immune/Lymphatic Systems Helps protect the body from disease Collects fluid lost from blood vessels and returns it to the circulatory system
Main Parts of the Immune/Lymphatic System White blood cells Thymus Spleen Lymph Nodes Lymph Vessels
Immune/Lymphatic System Random Facts Skin is the first line of defense Inflammatory response (swelling), actions of interferons (slows down the production of viruses) and fever (speeds up our immune response and stops some pathogens) are the second line of defense Your body recognizes itself and foreign substances and produces antibodies Vaccines are a weakened form of a pathogen so our body recognizes the real pathogen Passive immunity happens through breast feeding and through the placenta Lymph nodes act as filters, trapping microorganisms
Muscular System Works with skeletal system to produce voluntary movement Helps to circulate blood and move food through the digestive system
Main Parts of the Muscular System Skeletal Muscle Smooth Muscle Cardiac Muscle
Muscular System Random Facts Smooth and cardiac muscle are not under direct control of the central nervous system Contracting and relaxing happens when individual fibers slide past each other There are red and white muscle fibers (red muscles contain many mitochondria and are useful for long-distance running)
Skeletal System Supports the body Protects internal organs Allows movement Stores mineral reserves Contains cells that produce blood cells
Main Parts of the Skeletal System Bones Cartilage Ligaments Tendons
Skeletal System Random Facts Nerves and blood vessels run through bone in channels called Haversian canals Red bone marrow contains stem cells that produce most types of blood cells The skeleton of a human embryo is made up mostly of cartilage and becomes ossified to form bone. When growth plates become completely ossified the person stops growing. Types of Joints: Immovable joints (skull), slightly movable joints (vertebrae) and freely movable joints (shoulder, leg, etc).
Respiratory System Brings in oxygen needed for cellular respiration and removes excess carbon dioxide from the body
Main Parts of the Respiratory System Nose Pharynx Larynx Trachea Bronchi Bronchioles Lungs
Respiratory System Random Facts When you swallow food or liquid a flap of tissue called the epiglottis covers the entrance to the trachea to that food doesn t go into the trachea. Inhaled air: 21% oxygen,.04% carbon dioxide Exhaled air: 15 % oxygen, 4 % carbon dioxide The diaphragm controls air coming into and going out of your lungs Only 30% of male smokers live to age 80 but 55% of male nonsmokers live to that age.
Digestive System Breaks down food Absorbs nutrients Eliminates wastes
Main Parts of the Digestive System Mouth Pharynx Esophagus Stomach Small Intestine Large Intestine Rectum
Digestive System Random Facts Mechanical vs. Chemical Digestion Peristalsis occurs in the esophagus Overeating or drinking excess caffeine can cause a backflow of stomach acid into the esophagus Chyme is a mixture with an oatmeal-like consistency which then enters the small intestine The pancreas produces sodium bicarbonate which neutralizes stomach acid in chyme The small intestine is longer than the large intestine
Excretory System Eliminates waste products from the body
Main Parts of the Excretory System Skin Lungs Liver Kidneys Ureters Urinary bladder Urethra
Excretory System Random Facts Kidneys remove urea (produced in liver), excess water and minerals Each kidney contains nearly a million nephrons (which filter out wastes)
Endocrine System Controls growth, development and metabolism Maintains homeostasis
Main Parts of the Endocrine System Hypothalamus Pituitary Thyroid Parathyroids Adrenals Pancreas Ovaries Testes
Endocrine System Random Facts Hormones are released and only cells that have receptors for that hormone will respond. Insulin (glucose to glycogen) and glucagon (glycogen to glucose) counteract each other Pituitary gland produces growth hormone Adrenal glands control blood pressure, flight or fight response, etc. Thyroid controls metabolism
Reproductive System Produces gametes In females, nurtures and protects developing embryo
Main Parts of the Reproductive System Testes Epididymis Vas deferens Urethra Ovaries Fallopian tubes Uterus