1. Nutrition
1.1. Stages of food processing
1.1.1. INGESTION: taking in nutrients (eating and drinking)
1.1.2. DIGESTION: breaking down food molecules into simplier nutrient molecules (chemically and physically)
1.1.3. ABSORPTION: simpler nutrient molecules are absorbed via INTESTINES and released into the bloodstream
1.1.4. EGESTION/EXCREATION: removal of undigested food waste from the body
1.2. Nutrients: nutrients are required to preform LIFE FUNCTIONS and obtain ENERGY for survival
1.2.1. There are 6 groups of nutrients
1.2.1.1. Carbohydrates: a family of organic molecules composed of CARBON, HYDROGEN, AND OXYGEN.
1.2.1.1.1. General carbohydrate formula: (CH2O)x
1.2.1.1.2. SHORT TERM energy storage
1.2.1.1.3. 3 types of carbohydrates: monosaccharide, disaccharide, and polysaccharide
1.2.1.1.4. Digestion of Carbohydrates: MAJOR source of ENERGY for cellular respiration, monosaccharides provide QUICK ENERGY because they do NOT need to be digested.
1.2.1.2. Lipids: LONG TERM energy storage. Fats cushion and PROTECT organs and joints, fat under the skin helps INSULATE the body
1.2.1.2.1. Examples of lipids: phospholipids (in cell membrane), steroids (hormoes/cholesterol), fats (TRIGLYCERIDES) (made of 3 fatty acids)
1.2.1.3. Proteins: gives cells SUPPORT and shape (cytoskeleton), provides STRUCTURE (muscles, skin, organs, hair), forms STRUCTURES that transport substances across membranes, ENZYMES (important, we need it to digest shit) (CATALYSTS that speed up chemical reactions in the cell)
1.2.1.3.1. Structure: proteins are long chains of AMINO ACIDS. there are 20 amino acids, 9 of which are ESSENTIAL as our bodies cannot synthesize them. Amino acids are JOINED together by PEPTIDE BONDS. Chains of amino acids are called POLYPEPTIDES. A single protein may contain 1 or more polypeptide chain
1.2.1.4. Nucleic acids: NOT used as a nutrient.
1.2.1.4.1. SEE NOTES FROM GENETICS UNIT TO REVIEW NUCLEIC ACID STRUCTURE AND FUNCTION
1.2.1.5. Vitamins/minerals
1.2.1.5.1. Vitamins: CANNOT be used for ENERGY. May act as CO-ENZYMES (helps enzymes carry out their function)
1.2.1.5.2. Minerals: CANNOT be used for energy.
1.2.1.6. Water functions: transporting NUTRIENTS, eleminating wastes, lubricating joints, forming BODILY FLUID (blood and mucus), regulating BODY TEMP (ex. sweating)
1.2.2. Nutrients can be classified into two types: macro and micro nutrients
1.2.2.1. Macronutrients: needed in LARGE QUANTITIES
1.2.2.1.1. Ex. Carbohydrates, lipids, and proteins
1.2.2.2. Micronutrients: needed in SMALL quantities
1.2.2.2.1. Ex. Minerals and vitamins
1.2.3. Fibers: fibers aid in digestion. Consists of CELLULOSE which cannot be digested. keeps undigested food moist and soft( preventing constipation), physically SCRUBS digestive tract (cleans to remove toxins)
2. Human Digestive System: used to BREAK DOWN food and drink into their smallest parts through MECHANICAL and CHEMICAL means. These parts are ABSORBED and TRANSPORTED throughout the circulatory system to nourish all your cells and provide them with ENERGY.
2.1. Digestive system and circulatory system works together to provide the body with nutrients, as without the circulatory system, the nutrients wouldn't be able to be distributed throughout the body
2.2. There are two types of digestion: Mechanical and chemical
2.2.1. Mechanical digestion: the PHYSICAL breakdown of food by crushing/chewing in MOUTH and grinding of food by STOMACH muscles. Increases the SURFACE AREA of food for EXPOSURE to digestive chemicals.
2.2.2. Chemical digestion: the breakdown of food through CHEMICAL means (bile, enzymes, acids). These SIMPLER units can be absorbed by the SMALL INTESTINE.
2.3. The digestive system is made of two major components: the DIGESTIVE TRACT (alimentary canal), and the ACCESSORY ORGANS
2.3.1. Digestive tract: one CONTINUOUS tube from MOUTH TO ANUS. Aprox. 6.5M - 9M LONG.
2.3.1.1. Includes mouth, esophagus, stomach, small intestine, large intestine, rectum, and anus.
2.3.1.1.1. Mouth: uses tongue, teeth for MECHANICAL BREAKDOWN. Uses SALVIA for chemical breakdown
2.3.1.1.2. Esophagus: Long, muscular tube (25~cm) that connects the PHARYNX to the STOMACH.
2.3.1.1.3. Stomach: muscular, J-SHAPED sac-like structure that expands as it fills with food.
2.3.1.1.4. Small intestine: a coiled tube that's 2.5cm wide and roughly 7m long.
2.3.1.1.5. Large intestine: Has a wider diameter than the small intestine
2.3.2. Accessory organs: Organs INVOLVED in digestion but are NOT part of the digestive tract. Food does NOT pass through them but produce chemicals to help digest things. They have DUCTS to release chemicals into digestive system.
2.3.2.1. Includes Liver, pancreas, and galbladder.
2.3.2.1.1. Liver: produces BILE, DETOXIFIES alchohol and drugs, stores GLYCOGEN, manufactures BLOOD PROTEINS (albumin, globulin), recycles iron from RED BLOOD CELLS, and stores FAT SOLUABLE
2.3.2.1.2. Gallbladder: STORES bile produced by the liver until it is signalled to RELEASE it into the small intestine (DUODENUM)
2.3.2.1.3. Pancreas: produces pancreatic juices and regulates blood sugar levels.
2.4. Digesting Macromolecules: ENZYMES
2.4.1. Carbohydrates, proteins, and lipids are large, complex MACROMOLECULES. They need to be DIGESTED (broken down into simplier units before they can be absorbed by the SMALL INTESTINE)
2.4.1.1. Enzyme function DEPENDS on the environmental conditions in which the enzyme is found.
2.4.1.1.1. The OPTIMAL conditions for an enzyme DEPENDS on: pH (varies based on location of digestion, mouth, stomach, etc), TEMPERATURE (37 degrees), and presence of ACCESSORY molecules
2.4.2. ENZYMES are used to speed up the process of chemically digesting macromolecules
2.4.2.1. This chemically breakdown is called HYDROLYSIS. In a hydrolysis reaction, WATER is added to a macromolecule to break it down into smaller units by breaking down the BONDS between subunits
2.4.3. Major classes of enzymes: carbohydrase, lipase, protease, and nuclease
2.4.3.1. Carbohydrase: BREAKS DOWN polysaccharides and disaccharides. PRODUCES monosaccharide
2.4.3.2. Lipase: BREAKS DOWN triglycerides. PRODUCES glyceral and fatty acid
2.4.3.3. Protease: BREAKS DOWN proteins. PRODUCES amino acid
2.4.3.4. Nuclease: BREAKS DOWN nucleic acids. PRODUCES OH and phosphate
2.4.4. SALIVARY enzymes work optimally in a pH environment of 7. PEPSIN (stomach) enzymes work optimally in ACIDIC environments (2-3), TRIPSIN (small intestine) work optimally in an environment with a pH of 8-9.
2.4.4.1. PEPSIN (AKA PROTESE) begins as an inactive enzyme known as PEPSINOGEN, and turns into pepsin when gastric juices in the stomach are released. Optimal conditions are the acidic pH levels of 2-3
3. Circulatory system: The circulatory system works to carry NUTRIENTS to and WASTES from cells. Transport dissolved GASES and HOREMONS (chemical messengers). Regulates TEMPERATURE. Highway for cells of the immune system.
3.1. Contains 3 key components: Blood, blood vessels, and the heart.
3.1.1. Blood: BLOOD is a fluid tissues that acts as a CONNECTIVE TISSUE since it links all cells and organs together in the body.
3.1.1.1. There are four components of blood: Erythrocytes, Leukocytes, Platelets, and Plasma
3.1.1.1.1. Erythrocytes: AKA RED BLOOD CELLS, transports OXYGEN using hemoglobin from the lungs to the body tissue. HEMOGLOBIN is an IRON CONTAINING PROTEIN with a high affinity to oxygen. They have NO NUCLEUS to make space for oxygen
3.1.1.1.2. Leukocytes: (white blood cells) Helps the body fight against INFECTION or FOREIGN materials. Have a NUCLEUS.
3.1.1.1.3. Thrombocytes (PLATELETS): small CELL FRAGMENTS with no nucleus. Initiates blood clotting reaction (COAGULATION): platelets from sticky TENTACLES that allow them to stick to one another across the SURFACE of a damanged blood vessel to stop the BLEEDING.
3.1.1.1.4. Plasma: fluid medium which TRANSPORTS the following around the body: water, proteins, dissolved gases (CO2, O2), nutrients (glucose/vitamins), wastes and hormones.
3.1.1.2. When putting blood into centrifuge the result will be: 55% plasma (floating on top), 1% white blood cells and platelets (middle), and 44% red blood cells (on the bottom because they're filled with iron, so it makes them heavier.)
3.1.2. Blood vessels
3.1.2.1. TUBES that carry blood. Arteries/arterioles carry blood AWAY from the heart while veins/venules carry blood TO the heart.
3.1.2.1.1. There are FIVE main types of blood vessels: ARTERIES, ARTERIOLES, CAPILLARIES, VENULES, and VEINS
3.1.3. The heart: a hollow MUSCULAR organ that contracts repeatedly without fatigue. Located between the lungs in the THORACIC CAVITY. Protected by a protective layer of thin tissue
3.1.3.1. The heart is mainly composed of muscle and has FOUR CHAMBERS, FOUR VALVES, TWO ARTERIES, and TWO VEINS
3.1.3.1.1. Veins: SUPERIOR VENA CAVA, INFERIOR VENA CAVA, and the PULMONARY VEINS
3.1.3.1.2. Arteries: AORTA, PULMONARY ARTERIES
3.1.3.1.3. Chambers: RIGHT ATRIUM, RIGHT VENTRICLE, LEFT ATRIUM, LEFT VENTRICLE.
3.1.3.1.4. Valves: TRICUSPID VALVE, MITRAL (BICUSPID) VALVE, PULMONARY VALVE, AORTIC VALVE
3.1.3.1.5. Septum: a wall of muscle that seperates left and right pumps of the heart.
3.1.3.2. For diagrams: blue repersents DEOXYGENATED BLOOD (blood that has already delivered its oxygen content to cells), and red repersents OXYGENATED BLOOD (blood thats rich in oxygen that it received from the lungs)
3.1.3.3. "lub dub": the mamalian heart makes a "lud dub" sound as it pumps blood.
3.1.3.3.1. Lub sound: ATRIOVENTRICULAR valves closing
3.1.3.3.2. Dub sound: SEMILUNAR valves closing
3.1.3.4. Cardiac cycle: has two parts, SYSTOLE AND DIASTOLE
3.1.3.4.1. Systole: contraction of the VENTRICLES (blood is pushed OUT of the heart). AV VALVES shut to prevent blood from going back up into the atria.The shutting of these valves creates the "LUB sound"
3.1.3.4.2. Diastole: RELAXATION of the heart (heart fills with blood). SL VALVES shut to prevent blood from going back into the ventricles from the arteries. Shutting of these valves creates a "DUB" sound
3.1.3.5. Three kinds of circulation: SYSTEMATIC, CARDIAC, and PULMONARY
3.1.3.5.1. Systematic circulation: blood flow between the heart and the rest of the body (biggest kind of circulation)
3.1.3.5.2. Cardiac: blood flow within the heart.
3.1.3.5.3. Pulmonary: blood flow between the heart and the lungs.
3.1.3.6. Evolution of the heart: the heart evolved from a TWO-CHAMBER structure (in fish) into a THREE CHAMBER structure (in frogs and amphibians), and then into a FOUR CHAMBER structure (in birds and mammals.)
3.1.3.6.1. Evolution of the circulatory system (not relavent to exams): Unicellular and simple multicellular organisms do not need circulatory systems are they rely on DIFFUSION and OSMOSIS. Circulatory systems are an EVOLUTIONARY ADAPTATION to increase in size.
3.1.3.7. Control of the Heartbeat: The cardiac muscle has the capacity to cause its OWN CONTRACTIONS through electrical impulses. This, the nervous system controls the rate of the heart
3.1.3.7.1. Process:
3.1.3.7.2. Resting heart rate is about 70 beats/min but can be adjusted based on the body's needs and the health of the individual
3.1.3.7.3. An electrocardiogram is an electronic device that records the changing electrical currents produced by the SA and AV nodes fired impulses. The device produces a print out that can be used to diagnose any heart beat irregularities
3.1.3.7.4. Blood pressure: Blood pressure refers to the strength of the blood that is being pushed against the sides of the blood vessels. It is measured in mmHg using a sphygmomanometer
4. Respiratory System: responsible for providing the OXYGEN needed by every cell in the body. Removes waste products (carbon dioxide) that are formed by CELLULAR RESPIRATION
4.1. There are four stages of respiration: breathing, gas exchange, internal respiration, cellular respiration
4.1.1. Breathing: INSPIRATION (breathing in) and EXPIRATION (breathing out)
4.1.2. Gas Exchange: Exchange of CO2 and O2 between the RED BLOOD CELLS and ALVEOLI
4.1.2.1. Process of gas exchange occurs differently in AQUATIC and TERRESTRIAL ENVIRONMENTS
4.1.2.1.1. Aquatic: Aquatic environments contain dissolved OXYGEN already. Many aquatic organisms have evolved to use GILLS since it allows for water (containing gases) to move in and out
4.1.2.1.2. Terrestrial: Air does not flow in and out of our LUNG automatically, 2 sets of muscles are involved: the DIAPHRAGM and INTERCOSTAL (ribcage)
4.1.2.1.3. Mechanics of gas exchange: There is a HIGHER CONCENTRACTION of OXYGEN in the alveoli compared to the RED BLOOD CELLS in the capillary. Oxygen will difuse into the red blood cells. These blood cells carry and deliver oxygen to the remaining body cells.
4.1.3. Internal Respiration: exchange of gases between RED BLOOD CELLS and BODY TISSUE cells
4.1.4. Cellular Respiration: using O2 in a series of ENERGY-RELEASING chemical reactions and producing WASTE products, such as O2
4.1.4.1. Repiratory Surfaces must have the following two characteristics: must be LARGE enough for GAS EXCHANGE to occur quickly. Must be in a MOIST enivronment so that gases are dissolvved into AQUEOUS ENVIRONMENTS
4.1.4.1.1. 4 different types of respiratory surfaces: ourter skin (earth worms), gills (fish), tracheal system (insects, and lungs (humans)
4.2. Spirographs: a graph that repersents the amount of air that moves in and our of the lungs. We use it to measure lung volumes.
4.2.1. Tidal volume: the volume of air that is being inhaled and exhaled in a NORMAL BREATHING MOVEMENT when the body is at rest
4.2.2. Inspiratory reserve volume: the ADDITIONAL volume of air that can be taken into the lungs after a normal breath (or tidal inhalation)
4.2.3. Expiratory reserve volume: the ADDITIONAL volume of air that can be FORCED OUT of the lungs beyond a tidal exhalation
4.2.4. Vital capacity: the TOTAL VOLUME OF GAS that can be moved in and out of the lungs. Tidal + inspiratory + expiratory
4.2.5. Residual volume: the amount of gas that REMAINS in the lung's passageways to prevent the lungs and passageways from collapsing
4.3. Main components of the respiratory system: Nasal cavity, glottis, pharynx (throat), larynx, trachea, alveoli, left and right lungs, ribs, bronchioles, diaphragm, and bronchus.
4.3.1. Nasal cavity: CLEANS the air (removes bacteria and pollutants via CILIA). WARMS the air using its blood vessels. Moistens the air using MUCUS (making sure the air doesn't dry the respiratory system out)
4.3.2. Pharynx (throat): Air passes through the pharynx. The place where the nasal cavity, esophagus, and trachea meet (final location where air and food travel together)
4.3.3. Glottis: Opening of the trachea
4.3.4. Epiglottis: a flap of cartilage that controls the opening of the trachea and esophagus. Ensures only food enters the ESOPHAGUS and only air enters the TRACHEA. Choking occurs if food gets trapped in the trachea (epiglottis didn't chose properly)
4.3.5. Larynx: air passes through the larynx, causing our vocal cords to vibrate, creating the sound of our voice
4.3.6. Trachea: composed of rings of cartilage (soft bone). Helps maintain regidity to prevent respiratory system from collapsing
4.3.7. Bronchus: the trachea branches into 2 BRONCHIOLES, eventually leading to alveoli.
4.3.8. Trachea and bronchi: lined with epithelial cells. These cells produce mucus to trap foreign particles. CILIA (hairlike projections) brush mucus up the respiratory tract
4.3.9. ALVEOLI: Tiny air sacs in the lungs that increase SURFACE AREA. Alveoli are surrounded by CAPILLARIES for GAS EXCHANGE (Get O2 into blood and CO2 out). Alveoli are 1 cell thick to allow for RAPID DIFFUSION. Moist