INTRODUCTION TO BODY STRUCTURE BODY ORGANIZATION 1 The
INTRODUCTION TO BODY STRUCTURE
BODY ORGANIZATION 1. The levels of organization of the body: cells- individual unit tissues- Similar cells that work together to perform a common function. organs- Combination of 2 or more tissues that work together to perform a common function organ system- Group of organs that work together to perform a specific function.
BODY ORGANIZATION Maintaining homeostasis requires: 1. 2. 3. 4. 5. Body’s organs functioning together. Temperature regulation (endotherms) Adjusting metabolism Detecting and responding to stimuli Maintaining water and mineral balances
Integumentary System Consists of: Skin, Hair, & Nails
Skin The largest organ in your body. Yes, skin is an organ. n Functions of the Skin n n Protective barrier against pathogens Prevents water loss Offers body protection Regulates body temperature through sweating
Four Tissues of the Integumentary System • Epithelial- covers body surfaces • Connective- provides support and protection • Muscle – body movement • Nerve- forms body’s communication network
3 layers of skin 1. Epidermis: Top layer n n n Constantly makes new skin cells to replace dead ones Contains keratin, which as a waterproof barrier Also contains melanin, a brown pigment that helps protect you from UV rays. (This is why people tan)
3 layers of skin 2. Dermis: The 2 nd layer of skin n Contains hair follicles (each follicle contains 1 hair) Contains the sebaceous glands which produce an oil called sebum. This lubricates the skin and hair. Contains sweat glands. These release water and some wastes to cool the body and maintain homeostasis
3 layers of skin 3. Subcutaneous tissue: The 3 rd layer n n Composed of fat cells This is used for insulation and an energy supply
SKIN LAYER DIAGRAM EPIDERMIS SEBACEOUS DERMIS GLAND SUBCUTANEOUS TISSUE HAIR FOLLICLE SWEAT GLAND
SKELETAL SYSTEM Functions of the skeleton: 1. 2. 3. Support the body Provide protection for the internal organs Enables movement
SKELETAL SYSTEM There are 206 bones in the skeleton. The skeleton is divided into 2 parts: 1. axial- includes the skull, spine, ribs, and sternum 2. appendicular- includes shoulders, arms, hips, and legs
SKELETAL SYSTEM Bone is made of hard compact bone surrounding porous bone.
BONE MARROW n RED – makes all blood cells for body (RBC, WBC, & platelets) n YELLOW = stores fat tissue
SKELETAL SYSTEM Early in development, the skeleton is made mostly of hyaline cartilage. Bones hardens as calcium, phosphate and other mineral deposits build up. Osteoblasts make bone tissue. Bones thicken and elongate as development continues.
SKELETAL SYSTEM JOINT = where 2 bones meet. Three types of joints: 1. Immovable permits little or no movement. ex. skull joined by sutures. 2. Slightly moveable ex. Spine and ribs 3. Freely moveable joints (see table 2 p. 854) ex. knee
SKELETAL SYSTEM 1. Ligament: Connects bone to bone 2. Tendon: Connects muscle to bone
Osteogenesis Imperfecta
MUSCULAR SYSTEM Functions Include: n Movement in body n Generate Heat for Body Temperature
MUSCLES Involuntary muscles – not under conscious control. 1. Smooth muscles – line internal organs & blood vessels. a. Function of smooth muscle is to contract. b. Smooth muscle contractions are slow.
MUSCLE 2. Cardiac muscle – heart muscle. Adapted to conduct electrical impulse.
MUSCLE Voluntary muscles – under conscious control skeletal system. 3. Skeletal muscles – attached to the bones & skeletal system. a. Majority of muscles are skeletal b. Contractions are short & strong
MUSCLE Page skeletal muscle structure 1. Skeletal muscle are made up of bundles of muscle fibers. 2. Each muscle fiber is made up of myofibrils.
MUSCLE 3. Myofibrils are made up of smaller proteins filaments. a. Myofibrils are striated or divided into sections called sarcomeres which are the functional units of the muscle
MUSCLE 4. Two types of filaments a. Thick filaments are made up myosin. b. Thin filaments are made up of actin.
MUSCLES Sliding Filament Theory 1. during contractions, actin filaments move towards one another from the pulls of myosin heads
Muscle Fiber n Muscle contractions take a lot of ATP therefore they must have plenty of mitochondria to supply the power.
n Tendons connect bone to muscle.
Muscular Dystrophy
Human Excretory System
Human Excretory System Excretion is the removal of metabolic wastes from the body, including toxic chemicals, excess water, carbon dioxide and salts. n Excretory Organs n Skin n Lungs n Kidneys https: //www. youtube. com/watch? v=Ehn. Rhf. FLy. Og n
Human Urinary System Diagram Nephron Kidney Ureter Urinary Bladder Urethra
Urinary system The urinary system, consisting of the kidneys, ureters, urinary bladder and urethra, is responsible for eliminating the majority of metabolic wastes from the body n The functional unit of the kidney is the nephron. Each nephron is made of a cupshaped portion called Bowman’s capsule, tubules and a network of capillaries n
Inside the Kidney n n Blood pressure within a knot of capillaries (called the glomerulus) increases, causing most of the fluid of the blood to enter Bowman’s capsule This fluid is called filtrate. n n As the filtrate passes through the tubule portion of the nephron, materials needed by the body are reabsorbed and the remainder of the filtrate becomes urine Proper functioning of the kidney is essential to maintaining homeostatsis in the body
Warm-Up n Write down in correct sequence all the organs (at least 5) through which their food passes as it travels along the digestive tract. Then try to list any glands or organs that are found along the digestive tract, but through which food does not pass.
DIGESTION ANIMATIONS https: //www. youtube. com/watch? v=bo 2 Ape 8 JHq. A n https: //www. youtube. com/watch? v=08 Vy. JO Ec. Dos n https: //www. youtube. com/watch? v=Mq 9 f. Wz O 7 Dvw n
Cool Facts n n n Your intestines will grow to at least 25 feet as an adult. Be glad you're not a full-grown horse their coiled-up intestines are 89 feet long! Food sloshing in the stomach can last 3 -4 hours It takes 3 hours for food to move through the intestine Food drying up and hanging out in the large intestine can last 18 hours to 2 days! Americans eat over 2 billion pounds of chocolate a year. In your lifetime, your digestive system may handle about 50 tons!!
Human Digestive System
Structures n The Gastrointestina. I tract (GI), also called the alimentary canal is the system of organs that take in food, digest it to extract nutrients and expels the waste. These organs are the mouth, pharynx, esophagus, stomach, small intestine and large intestine. n Major Functions: n n Ingestion Digestion Absorption Defecation or Excretion
Following the Trail n The process begins in the mouth. n n n Chewing initiates mechanical breakdown of food and is followed by secretion of saliva, which moistens and lubricates food for swallowing. Saliva also contains amylases (enzymes), which start the chemical breakdown of carbohydrates. The swallowing reflex begins in the pharynx and initiates rhythmic waves of smooth muscle contractions called peristalsis. n Peristaltic contractions transport food to the stomach and allow a person to swallow even if he/she are upside down.
Human Digestive System • Digestion is the ability to process food in the body into a form that can be absorbed and used or excreted. n Digestion involves three principle processes: n n n Mechanical digestion: takes place in the mouth, your teeth chew the food Chemical digestion: using chemicals to digest/ break down food, this takes place in your mouth and stomach where acid and enzymes mix with the food. Absorption: pulling nutrients out of the food, occurs in the small intestine
n Accessory organs: Organs that help with digestion but are not part of the digestive tract. These organs are the tongue, salivary glands, liver, gall bladder, and pancreas.
Human Digestive System Diagram Mouth Pharynx Esophagus Liver Stomach Large Intestine Small Intestine Villi
Following the Trail II n The stomach contains an extra layer of muscle that aids in mechanically mixing and churning food into a semiliquid form called “chyme. ” n n Chemical digestion begins with proteins through the action of hydrochloric acid (HCl) and the enzyme, pepsin. Only water and a few substances, such as aspirin and alcohol, are absorbed by the lining of the stomach.
Following the Trail III n As food enters the small intestine secretions from the liver, gall bladder and pancreas are added.
The small intestine completes digestion of food materials by absorbing nutrients into the blood stream n The lining of the small intestine consists of tiny folds or fingerlike projections, called villi, which, in turn, are covered by microvilli which increase surface area n n n The villi contain capillaries and lymphatic vessels for the absorption of nutrients Microvilli have brush border enzymes to hydrolyze lactose and sucrose.
Cross-Section of small intestine Villi Microvilli
n The large intestine does not contain villi and it plays no role in digestion Only water and vitamin K are absorbed from the large intestine n Undigested or unabsorbed food is eliminated through the rectum and then anus. n
Nutrition n Food materials are broken down to usable nutrients and absorbed into the bloodstream. n n They are used by the body for metabolism, building and repair Some nutrients are stored within the body Nutrients include carbohydrates, proteins, lipids, vitamins, minerals and water. Carbohydrates n n Must be broken down into monosaccharides Body’s main source of energy.
Nutrition II n Proteins n n Broken down to amino acids Supply the raw materials for growth and repair. The body requires 20 amino acids, 10 of which it cannot make and must obtain Lipids are reduced to fatty acids and glycerol n n They are used to make steroid hormones, cell membranes Store energy
n Nucleic acids are reduced to nucleotides. n DNA and RNA n The genetic material of all cells.
Where does each nutrient get broken down?
Carb. Digestion Protein Digestion Nucleic Acid Digestion Fat Digestion Mouth, Polysacch. Throat, Into Esophagus Disacch. Stomach Small Intestine Polypepties DNA, RNA into smaller into proteins nucleotides Disacch. Small Nucleotides Into proteins into nitrogen Monosacch. amino acids base, sugar and phospate Fat into glycerol, fatty acids and glycerides
What enzymes break down each nutrient? Protein Carb Digestion Nucleic Acid Digestion Salivary amylase Peptidases Nucleotidases (amino acids are connected by “peptide” bonds) (nucleotides are building block of DNA and RNA) (amylose is starch, a polysacch) Fat Digestion Bile salts and Lipase (fats are made of lipids)
Nutrition III n Vitamins are organic molecules that aid in the regulation of body processes n Vitamin C: healthy teeth, gums and blood vessels; improves iron absorption and resistance to infection n Vitamin K: for normal blood clotting and synthesis of proteins found in plasma, bone, and kidneys
n Water n n n Required for metabolism and chemical reactions within the body Transport of substances around the body Regulation of body temperature. Approximately two-thirds of the body weight is water.
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