Human Body Systems: An Overview
Body systems overview,
Functions
Integumentary – helps regulate body temp, removes excretory waste (urea, water), protects against sun’s UV rays, produces vitamin D
Skeletal – protects organs, provides shape/support, stores materials (fats, minerals), produces blood cells, allows movement
Muscular – Allows for movement by contracting
Nervous – gathers and interprets information, responds to information, helps maintain homeostasis
Endocrine – Regulates body activities using hormones, Slow response, long lasting
Circulatory – Carries and delivers important substances throughout the body to the cells, picks up waste material from the cells
Lymphatic – stores and carries WBC’s that fight disease, collects excess fluid and returns it to blood
Respiratory – Provides a way for oxygen from the air to enter the body, Delivers oxygen to the blood, removes and releases carbon dioxide from the blood
Digestive – Digestion is the breakdown of food into simpler forms that can be used by cells, physical/mechanical and chemical changes
Urinary – Get rid of waste produced from the body cellular processes, produces urine, filters blood
Reproductive – Allows organisms to reproduce which prevents their species from becoming extinct.
Organs- Same order as above
Skin
Bones, Cartilage, ligaments
Cardiac muscle, Smooth muscle, Skeletal muscle, tendons, ligaments, cartilage
Brain, Spinal cord, Nerves, Nerve cells = neurons, hypothalamus
Glands (Hypothalamus, Pituitary, Thyroid, Thymus, Adrenal, Pancreas, Ovaries, Testes)
Heart, Veins, Arteries, Capillaries, Red blood cells
Lymph (liquid part of blood – plasma, when it’s in lymph vessels), Lymph Vessels, Lymph Nodes, WBCs
Nose, Trachea, Bronchi, Bronchioles, Alveoli, lungs, Diaphragm
Mouth, esophagus, stomach, Sm. Intestine, Lg. Intestine, rectum, anus, Salivary glands, pancreas, liver, gallbladder
Kidneys, Ureters, Bladder, Urethra
Ovaries (female; eggs), Testes (male; sperm) Ovaries *produce eggs Testes
Levels of organization (cell, tissue, organ, organ system, organism)
Skeletal system
Compact – the strong, dense outer layer of a bone
Spongy – the lightweight, inner layer of a bone that contains many small spaces
bone marrow – the tissue in the hollow part of the bone
Joint – Is the point where two or more bones meet together
Ligament – Is it connective tissue that holds the bones together
Cartilage – is a flexible connective tissue that protects bones as the bones rub against each other
Tendon – bones and muscles work together to create movement
Closed fracture – bone breaks but doesn’t come through the skin
Open fracture – bone breaks and comes through the skin
Stress fractures – Caused by repeated trauma to the same bone
Muscular system
Voluntary movement – muscle action under your control. EX: Skeletal muscles
involuntary movement – muscle action that isn’t under your control. EX: Smooth, skeletal, and cardiac muscles
Flexor – Muscle that bends part of your body. EX: bicep
Extensor – muscle that straightens part of your body. EX: tricep
Resistance exercises – strengthen skeletal muscles by working against the resistance or weight of an object; often used body weight. EX: Sit ups
aerobic exercise – increases endurance especially of the heart;
May also build strength. EX: jogging
Digestive system
Proteins (meat), Carbs (sugars = energy), Lipids (fats), Vitamins, minerals, water
Digestive tract – part of the digestive system that the food passes through. EX: Mouth, esophagus, stomach, small & large intestine, rectum & anus
accessory organs – Part of the digestive system that food does not pass through. EX: liver, gallbladder, pancreas
Mechanical digestion – Physical process in which food is crushed and mashed during chewing
chemical digestion – chemical process in which food is turned into a mushy substance using stomach acid, bile, saliva and other enzymes (proteins that speed up chemical reactions)
Mouth – John, teeth, & saliva change food into soft Mass (Bolus)
Esophagus – Muscular to moves food to stomach using peristalsis (muscular contractions)
Stomach – Muscular sac that turns food into a thin, watery liquid called chyme
Liver – Large red Brown organ that makes bile to break up fat, stores nutrients, and breaks down toxins
Gallbladder – stores bile and releases it into S.I to help break down fat
Pancreas – makes digestive enzymes and Insulin in which regulates blood sugar, produces fluid that flows into S.I and neutralizes acidic chyme | Small Intestine – Long tube (small diameter) that functions and chemical digestion and nutrient absorption
Large Intestine – absorbs water from undigested Chyme; Chyme can be in L.I as long as 3 days
Rectum & anus – Control release of solid waste (feces) from body
Integumentary System
Skin
Protects you by keeping water in your body and foreign particles out of your body, Keeps you in touch with the outside world; nerve endings in your skin allow you to feel things around you, helps regulate your body temperature by sweating and helps get rid of waste, Epidermis, dermis, hypodermis
Hair and {nails == Function – protects the tips of fingers and toes}
Gets color from chemical, melanin
protect skin from UV light, keep particles (dust/insects/etc.) out of eyes and nose, regulates body temperature by trapping near the body
Circulatory system
Atria – upper chambers of the heart that receive blood from veins and empty into the ventricles
Ventricles – lower chambers of the heart that receive blood from the atria and push it into the arteries
Valves – structures that ensure the flow of blood in one direction
Pulmonary circulation – flow of blood from the heart to the lungs and back to the heart through the pulmonary arteries, capillaries, and veins.
Systemic circulation – flow of blood from the heart to all parts of the body and back to the heart.
Arteries – blood vessels that carry blood away from the heart and to the body’s organs.
Capillaries – tiny blood vessels that allow the exchange between body cells and blood.
Veins – blood vessels that carry blood back to the heart.
Atherosclerosis – when cholesterol builds up inside of the blood vessels. Atherosclerosis is a major cause of heart diseases.
High Blood Pressure – Hypertension is abnormally high blood pressure. The higher the blood pressure, the greater the risk of a heart attack, heart failure, kidney disease, and stroke.
Heart Attack/Failure – A heart attack happens when heart muscle cells die and part of the heart muscle is damaged. Heart failure happens when the heart cannot pump enough blood to meet the body needs.
Plasma – the fluid part of blood. It is a mixture of water, minerals, nutrients, sugars, proteins, and other substances.
Red Blood Cells – Most blood cells are red blood cells (RBCs). RBCs take oxygen to every cell in your body.
Platelets – pieces of larger cells found in bone marrow. When you cut yourself, platelets help blood clot.
White Blood Cells (WBCs) – help keep you healthy by destroying pathogens. WBCs also help clean wounds.
Respiratory system
Nose and Mouth – passageways into/out of the respiratory system that helps to warm air
Pharynx (Throat) – transports air, food,and water; branches into 2 tubes- the esophagus and the larynx
Larynx (Voice Box) – part of the throat containing a pair of elastic bands known as vocal cords that stretch across the opening
Trachea (WindPipe) – carries air from larynx to lungs; covered in cartilage for protection
Bronchi/Bronchus/Bronchial tubes – two tubes (split off from trachea); one tube goes to each lung.
Bronchioles – tiny tubes branching from bronchito tiny sacs called alveoli
Alveoli: air sacs in the lungs that are surrounded by capillaries (O2 enters bloodstream and CO2 exits)
Diaphragm: dome shaped muscle below the lungs that contracts when you breathe to expand the volume of your chest cavity
Nervous system
Neuron: cell that carries nerve impulse information
Dendrites: delivers impulse to cell body
Cell body: contains nucleus & organelles
Axon: carries impulse away from cell body
Sensory neurons: gather information about what is happening in and around your body and send it to the CNS for processing. EX: detect light
Motor neurons: send messages from brain and spinal cord to other systems.EX cause muscles around eyes to squint when in bright light
Peripheral Nervous System (PNS): includes all nerves branching from the CNS to other parts of the body
Central Nervous System (CNS): Includes the brain and spinal cord; controls reflexes
Somatic Nervous System: neurons that stimulate skeletal muscles; controls things that you think about. EX: writing, talking, smiling, or jumping
Autonomic Nervous System: controls body functions that you do not think about- EX: digestion, heart rate
Cerebrum: largest part of brain; voluntary and involuntary actions —> thinking, sensing, and voluntary movement
Cerebellum: allows brain to keep track of your body’s position
Medulla: part of brain that connects to the spinal cord
Left part of your brain {speaking, reading, writing, and solving problems} controls right side of your body; right part of your brain {spatial thinking, processing music, and interpreting emotions} controls left side of your body
