Risk Factors *Obesity: °Stress °Genetics °Poor eating °Sedentary life °Age *Gastritis: °Alcohol abuse °Stress °Certain medications °Helicobacter pylori °Pernicious anemia °Bile reflux °Infections caused by bacteria or viruses *Cardiovascular disease: |Controllable °Smoking °Drug abuse °Weight gain °Exercise |Non-controllable °Genetics °Male gender °Ethnicity *Osteoporosis: |Non-controllable °Female gender °Age °Ethnicity (white or Asian) °Family history °Small frame size |Controllable °Hormone levels (too little estrogen or testosterone or too much thyroid or parathyroid hormone) °Dietary factors (anorexia, anemia, too little calcium) °Lifestyle choices (inactivity, smoking) Parts Of… *Nervous system: The nervous system is divided into the central nervous system (CNS), which consists of the brain and spinal cord, and the peripheral nervous system (PNS), which is made up of nerves and ganglia. There are 12 pairs of cranial nerves that leave the brain, and 31 pairs of spinal nerves the leave the spinal cord. Sensory Neurons Interneurons Motor Neurons Carry sensory information from the cranial and spinal nerves into the CNS. Found within the CNS receive sensory information and pass it to other interneurons or to motor neurons. Carry information from the CNS through nerves to effectors such as muscles or glands. *Endocrine system: °Hypothalamus: regulates body temperature, hunger, sleep, thirst, water balance; produces hypothalamic-releasing hormones and hypothalamic-inhibiting hormones, thus serving as a link between the nervous and endocrine systems. °Pituitary gland: neurosecretory cells produce the hormones antidiuretic hormone (ADH) when the blood is too concentrated and oxytocin for uterine contraction during child-birth. Thyroid-stimulating hormone (TSH) Adrenocorticotropic hormone (ACTH) Gonadotropic hormones (FSH and LH) Stimulates the thyroid to produce the thyroid hormones Stimulates the adrenal cortex to produce cortisol Stimulate the gonads to produce gametes and sex hormones. Prolactin (PRL) is only produced during pregnancy and after childbirth, and it causes the mammary glands to produce milk and suppress ovulation in the nursing mother. Growth hormone (GH) promotes skeletal and muscular growth. It increases the rate at which amino acids enter the cells and causes increased protein synthesis. It also promotes fat metabolism as opposed to glucose metabolism. Melanocyte-stimulating hormone, which has an unknown function in humans, regulates skin color in lower vertebrates. °Thyroid gland: thyroid hormones triiodothyronine (T3) and thyroxine (T4) that increase the metabolic rate. They do not have a single target organ, but rather they stimulate most cells of the body to metabolize more glucose and utilize more energy. The thyroid gland also produces a hormone called calcitonin, which helps control blood calcium levels. °Parathyroid gland: parathyroid hormone (PTH), which causes calcium blood levels to increase and blood phosphate levels to decrease. PTH promotes the activity of osteoclasts and the release of calcium form the bones, as well as the reabsorption of calcium by the kidneys, where it helps activate vitamin D. °Adrenal glands: Epinephrine (adrenaline) and norepinephrine (NE) produced by the adrenal medulla rapidly cause body changes that occur when someone reacts to an emergency in a fight-or-flight manner. Mineralocorticoids regulate salt and water balance, leading to increased blood volume and blood pressure. Glucocorticoids regulate carbohydrate, protein, and fat metabolism, leading to an increase in the blood glucose level. °Pancreas: Insulin promotes the storage of glucose as glycogen and the synthesis of proteins and fats, thereby lowering the blood glucose level to normal. Glucagon stimulates the liver to break down glycogen to glucose when the blood glucose level is low. °Gonads: Testosterone brings about and maintains the male secondary sex characteristics that develop during puberty, such as the growth of a beard, axillary hair, and pubic hair, it also prompts the larynx and the vocal cords to enlarge, resulting in voice change. Estrogen stimulates the growth of the uterus and the vagina and is necessary for egg maturation and the secondary sex characteristics in females, which include female body hair and fat distribution, more subcutaneous fat accumulation, and wider pelvic girdle. *Male reproductive system: *Female reproductive system: *Respiratory system: °Pharynx: connects the nasal and oral cavities to the larynx, passageway for both food and air. °Larynx: passageway for air between the pharynx and the trachea, contains the vocal cords. °Trachea: tubular passageway for air that is located anterior to the esophagus and extends from the larynx to the primary bronchi. °Bronchial tree: consists of the trachea, primary bronchi, secondary bronchi, tertiary bronchi, bronchioles, and terminal bronchioles. Each bronchiole leads to an elongated space enclosed by a multitude of air sacs called alveoli. °Lungs: paired cone-shaped organs that are found in the thoracic cavity. The right lung has three lobes, and the left lung has two lobes, allowing room for the heart. The alveolus is made up of simple squamous epithelium surrounded by blood capillaries. Gasses exchange occurs between the air in an alveolus and the blood in the capillaries. *Epidermis and dermis: |Epidermis °Keratinocytes (90% of the cells) produce keratin to protect from chemicals and microbes. Lamellar granules decrease water entry and lose. °Melanocytes (8% of the cells) transfer melanin granules to the keratinocytes, protecting the skin against UV damage. °Langerhans cells come from red bone marrow and into the epidermis, participating in immune responses against microbes that invade the skin, and are easily damaged by UV light. °Merkel cells (the less numerous cells) located in the deepest layer, contact part of a sensory neuron and detect different aspects of touch sensations. |Dermis Region of loose fibrous connective tissue beneath the epidermis. The dermis contains collagen and elastic fibers, which together provide the skin with strength, extensibility (the ability to stretch, and elasticity, the ability to return to its original shape after stretching). The extensibility of skin can be seen around joints and in pregnancy and obesity. *Axial skeleton: Made up of the bones in the midline of the body, which include the bones of the skull, the hyoid bone, the bones of the vertebral column, the bones of the rib cage, which include the vertebrae, the ribs and their associated cartilages, and the sternum, and the ossicles or bones of the middle ear. *Gastrointestinal tract: *Urinary system: °Kidneys: produce urine. °Ureters: extend from the kidneys to the bladder. Peristalsis moves urine through the ureters and causes urine to enter the bladder at a rate of about five jets per minute. °Bladder: expands as urine enters and can hold up to 600 ml of urine. A sphincter is a circular muscle that surrounds a tube. Two sphincters are found where the urethra exits that bladder. When these sphincters are closed, urination does not take place. °Urethra: expels urine from the bladder to outside the body. In females it is 4cm long, in males 20 cm. Types Of… *Diabetes: °Prediabetes: high blood sugar levels, yet not high enough to be diabetes type 2. °Type 1: diabetes mellitus, the pancreas produces little to no insulin. °Type 2: chronic disease affecting the way the body processes blood sugar. °Gestational: high blood sugar levels affecting pregnant woman. *Blood vessels: The cardiovascular system consists of three types of blood vessels that transport blood: the arteries (and arterioles), which carry blood away from the heart to the capillaries; the capillaries, which allow gas, nutrient and waste exchange to take place with the tissues; and the veins (and venules), which return blood from the capillaries to the heart. *Reflexes: A reflex is a fast, automatic, unplanned sequence of actions that occur in response to a specific stimulus. There are different types of reflexes, for example inborn reflexes such as pulling your hand away from something hot, and acquired reflexes that are learned, such as slamming on the breaks in an emergency. A reflex is called a spinal reflex when integration takes place in the spinal cord, and it is called a cranial reflex if integration occurs in the brain stem. An example of a spinal reflex is the patellar or knee jerk reflex, and an example of a cranial reflex is the tracking movements of your eyes as your read. Somatic reflexes involve the contraction of skeletal muscles, while autonomic reflexes, which are usually not perceived, involve the response of smooth muscle, cardiac muscle, and glands. Reflexes allow for protection and survival. *Exercises: *Hormones: °Sex hormones (testosterones, estrogen, progesterone). °Antagonistic hormones (opposite effects). °Steroid hormones (derived from cholesterol). °Peptide hormones (peptides, proteins, glycoproteins, and modified amino acids). *Skin cancer: °Squamous cell carcinoma: (20% of all skin cancers) starts in the squamous cells and have a variable tendency to spread. °Basal cell carcinoma: (78% of all skin cancers) starts in the basal cells, which produce new skin cells. It rarely metastasizes. °Melanoma: (2% of all skin cancers) starts in melanocytes, which produce melanin. They metastasize rapidly and can kill a person within months of diagnosis. *Cells: https://www.thoughtco.com/types-of-cells-in-the-body-373388 *Antagonistic hormones: °Calcitonin and PTH are considered to be antagonistic hormones because they have opposite effects. °Glucagon acts opposite to insulin, raising the blood glucose level to normal. *Bone cells: °Osteogenic cells are stem cells, and they are the only bones cells to undergo cell division, with the resulting daughter cells becoming osteoblasts. Osteogenic cells are found along the inner part of the periosteum, in the endosteum, and in the canals within bone that have blood vessels. °Osteoblasts are bone-building cells that synthesize and secrete collagen fibers and other organic components needed to build the matrix of bone tissue, and they initiate calcification. As osteoblast surround themselves with extracellular matrix, they become trapped in their secretions and become osteocytes. °Osteocytes are mature bone cells that are the main cells found in bone tissue, and maintain its daily metabolism, such as the exchange of nutrients and wastes with the blood. Like osteoblasts, osteocytes do not undergo cell division. °Osteoclasts are huge cells derived from the fusion of as many as 50 monocytes, a type of white blood cell, and are concentrated in the endosteum. On the side of the cell that faces the bone surface, the osteoclast’s plasma membrane is folded into a ruffled border. Here the cell releases powerful lysosomal enzymes and acids that digest the protein and mineral components of the underlying bone matrix. This breakdown of bone matrix, termed resorption is part of the normal development, growth, maintenance, and repair of bone. In response to certain hormones, osteoclasts help regulate blood calcium level. They are also target cells for drug therapy used to treat osteoporosis. *Drug dependence: Physical dependence Neurochemical changes require continued use of substance to maintain “abnormal” homeostasis Psychological dependence Effects from use of substance are desired and reinforce continued use Functions of the Integumentary System Endocrine and Exocrine Glands Cardiac Cycle Each heart beat is called a cardiac cycle, which consists of the first two atria contracting simultaneously, followed by the two ventricles contracting simultaneously, and finally, all the chambers relaxing. Systole refers to contraction of the heart muscle, while diastole refers to relaxation of the heart muscle. The heart beats about 70 times per minute, and each heart beat lasts about 0.85 second. Phases of Respiration Pulmonary ventilation or breathing consists of the inhalation (inflow) and exhalation (outflow) of air between the atmosphere and the alveoli of the lungs. To understand ventilation, it is important to recall that there is a continuous column of air from the pharynx to the alveoli of the lungs; the lungs lie within the thoracic cavity; and the lungs adhere to the thoracic wall by the pleura. External respiration is the exchange of gasses between the air in the alveoli and the blood in the pulmonary capillaries. Gasses exert pressure, and the amount of pressure each gas exerts is called its partial pressure. Blood in the pulmonary capillaries has a higher partial pressure of carbon dioxide that atmospheric air therefore carbon dioxide diffuses out of the plasma and into the lungs. The partial pressure of oxygen in the pulmonary capillaries is lower than in the alveoli, causing oxygen to diffuse into the plasma and then into red blood cells, where hemoglobin picks it up. Internal respiration refers to the exchange of gasses between blood in systemic capillaries and the tissue fluid. In this step, oxygen diffuses out of the blood and into the tissues because the partial pressure of oxygen in the tissue fluid is lower than that of blood. The lower partial pressure of oxygen is due to cells continuously using up oxygen in cellular respiration. Carbon dioxide diffuses into the blood from the tissues because the partial pressure of carbon dioxide of tissue fluid is higher than that of blood. Carbon dioxide is continuously produced by the cells and collects in the tissue fluid. Composition of Blood When blood is collected in a test tube and prevented from clotting by adding an anticoagulant, it separates into three layers. The top layer, which represents about 55% of the blood, is the plasma; the thin middle layer, which represents less than 1 % of blood, consists of leucocytes or white blood cells and platelets; and the bottom layer, which represents about 45% of blood, contains the erythrocytes or red blood cells. BMI Ranges BMI Weight Status < 18.5 Underweight 18.5-24.9 Normal 25.0-29.9 Overweight 30.0-34.9 Obese (Class I) 35.0-39.9 Obese (Class II) ≥ 40 Extremely Obese (Class III) Glycemic Index Vitamins A, D, E, K are Soluble In? Soluble in fat (fat-soluble vitamins).
