THE IMMUNE SYSTEM

The immune system is our body’s protection system. It is designed to defend against bacteria, viruses, and toxins that invade your body. T cells  signal the invasion B cells  make antibodies (chemical fighters) Macrophages  white blood cells that EAT

Lymph nodes Lymph nodes are filled with white blood cells. Lymph nodes are located throughout the body and swell when you’re fighting an infection because they work harder and collect dead cells. The main job of the lymph nodes is to filter the lymph (clear fluid that comes from tissues) by eliminating antibody-coated bacteria.

Bone marrow Bone marrow is the spongy tissue inside of bones (i.e. hip, breast, skull, ribs, vertebrae, shoulder blades, humerus, and femur). It has blood stem cells which can develop into any type of blood cell.

Thymus gland Precursor cells from the bone marrow travel to the thymus gland and here they develop into lymphocytes (white blood cells). Theses white blood cells will produce antibodies that fight bacteria and viruses.

Spleen Also produces lymphocytes Filters blood to removes old red blood cells Also removes antibody-coated bacteria Located in the upper-left part of the abdomen

Immune system disorders Primary immunodeficiency (born weak) Acquired immunodeficiency (becomes weak) Autoimmune disorders (destroys itself) ALS, multiple sclerosis, lupus, diabetes type 1 Overactive immune system Allergies Anaphylactic shock

THE DIGESTIVE SYSTEM

The digestive system is the organ system that takes in food, digests it, absorbs the nutrients, and excretes the remaining waste. The digestive system is made up of the digestive tract and 3 accessory organs. The parts of the digestive system in humans are shown here. Know the parts!

THE DIGESTIVE TRACT The tube in which the food travels through as it is digested (mouth, esophagus, stomach, small intestine, large intestine, rectum, anus)

THE ACCESSORY ORGANS (Liver, Gall bladder, Pancreas)

Mouth Breaks down food mechanically (teeth and tongue) Also breaks apart food chemically with saliva (enzymes and water) Saliva is produced in the epithelial tissue that lines the mouth

Esophagus A tube connecting your mouth to your stomach Surrounded by smooth muscle tissue which can contract/relax without conscious thought Nerve tissue controls muscle contractions Contractions slowly move along food

Stomach Holds and churns food Lining of inside of stomach has cells that produce digestive enzymes and acid Layers of smooth muscle tissue contract to mix stomach contents

Small Intestine After stomach in digestive tract Composed of smooth muscle 6m long, and narrow Goblet cells secrete mucus Does most digestion of food, and almost all absorption of nutrients

Large Intestine 1.5m long, and wider than small intestine Absorbs water after digestion Waste left-over goes to rectum where it is packed and stored temporarily Then anus, and out!

Accessory organs Liver Produces bile (which breaks down fat in food) Gallbladder Where bile is stored Pancreas Creates an enzyme called insulin to help regulate the concentration of sugar in our blood (either helps store it or send it to cells)

Digestive System Disorders Cancers Ulcers Diarrhea Constipation Lactose intolerance Heartburn / Gastroesophageal reflux disease Irritable bowel syndrome

THE MUSCULOSKELETAL SYSTEM

Musculoskeletal system Muscular system Skeletal System

The musculoskeletal system includes all of the bones and muscles in a body. It supports, protects, and moves the body.

Function of the Skeletal System Protection protect vital organs in the body (eg. skull protects brain, spine protects spinal cord, ribs protect heart and lungs Blood-cell production bone marrow in large bones produce blood cells and releases them into the blood stream

Support for your muscles Movement Mineral storage - bones made up of calcium and phosphorus giving bones strength and rigidity Support for your muscles Movement

Components of the Skeletal System The skeleton is composed of 3 types of connective tissue. Bone Ligaments Cartilage

Bone The human skeleton is composed of 206 bones Hard and dense tissue Bone is composed of bone cells within a matrix of minerals (calcium, phosphorus) and collagen fibers If your diet is not high in minerals, your body will absorb Ca and P from your bones causing them to weaken

Structure of Bone Canals inside the bones contain nerves and blood vessels Only a small percentage of the bone tissue is actually living

Ligaments (connect bone to bone) are strong tough elastic bands of connective tissue that can stretch Hold bones and movable joints together surround the joint to give support and limit the joint's movement

Cartilage hard but slippery tissue that covers the ends of bones where they meet to form a joint. made up of cells and collagen fibres and is wear-resistant helps reduce the friction of movement by allowing bones to glide over one another Absorbs the energy from the shock of physical movement Found in: Ears, nose, esophagus, joints, disks between vertebrae

Muscles Bones need muscles to move them There are about 600 muscles in the human body Made up of bundles of long cells called muscle fibres that contain specialized proteins

Muscle

Tendons (connect muscle to bone) another type of tough connective tissue on each side of a joint attach to muscles that control movement of the joint.

Types of Muscles Cardiac Muscle Smooth Muscle Skeletal Muscle involuntary in heart Smooth Muscle Involuntary in lining of organs (stomach, esophagus, uterus, intestines) Skeletal Muscle voluntary Attached to bone (bicep, tricep, deltoid)

Antagonistic Muscles One contracts while the other relaxes Work together to move bones Ex. Bicep and tricep, hamstring and quadricep

Problems with the Musculoskeletal System Arthritis Osteoporosis Broken bones Torn ligaments Torn tendons