Nursing LMs

nervous system

This document provides an overview of the senses, particularly the special senses of sight and hearing. It explains the concepts of sense, sensation, and perception, and how perception is primarily a function of the cerebral cortex. The document then goes on to discuss the different types of sensory receptors, such as mechanoreceptors, chemoreceptors, photoreceptors, thermoreceptors, and nociceptors. The anatomy of the eye is described in detail, including the three layers that make up the ey...

Chapter key points: Muscle fibers are organized into fasciculi, and fasciculi are organized into muscles by associated connective tissue. Each skeletal muscle fiber is a single cell containing numerous myofibrils. Myofibrils are composed of actin and myosin myofilaments. Sarcomeres are joined end-to-end to form myofibrils. Cell membranes have a negative charge on the inside relative to a positive charge outside. This is called the resting membrane potential. Action potentials a...

This text discusses the skeletal system including its functions, structure, types of bones, and joints. Some key points: The skeletal system provides support, protects organs, allows movement, stores minerals, and produces blood cells. The extracellular matrix of bone consists of collagen, proteoglycans, minerals and water. There are four categories of bone: long, short, flat, and irregular. Long bones have a shaft, ends, and growth plates. Bone tissue consists of osteoblasts, osteocytes,...

The text discusses the integumentary system, which consists of the skin, hair, glands, and nails. The skin performs several important functions, including protection, sensation, vitamin D production, temperature regulation, and excretion. The epidermis is the outer layer of skin and consists of stratified squamous epithelium divided into strata. The dermis is made of dense connective tissue and contains blood vessels, nerves, and skin appendages. Melanocytes in the dermis produce melanin that de...

This text discusses cell structure and function. Some key points: • Cells are the basic unit of life and consist of a nucleus, cytoplasm, and plasma membrane. The nucleus contains DNA which controls cell activity. The cytoplasm contains organelles that perform specific functions. • The plasma membrane regulates what enters and leaves the cell. Molecules can move across the membrane through passive diffusion, osmosis, or active carrier-mediated transport using protein channels and carri...

CHAPTER 6: Muscular System • Muscular Tissue o Contributes to homeostasis by producing body movements o Producing heat to maintain normal body temperature o Stabilize body position o Regulate organ volume o Propel fluids and food matter through various body systems • Introduction o Motion results from the alternating contraction and relaxation of muscles, which make up 40–50% of total adult body weight (depending on the percentage of body fat, gender, and exercise regimen). o Th...

This text discusses the structure and function of the human body. Some key points: • Anatomy is the study of body structure, while physiology focuses on function. The two are interrelated - structure determines function. • The human body is organized hierarchically from smallest to largest: chemical, cellular, tissue, organ, organ system, organism. • The body has 11 organ systems that work together to maintain life. These include the integumentary, skeletal, muscular, nervous, e...

The text discusses the urinary system and fluid balance in the human body. The urinary system consists of the kidneys, ureters, urinary bladder, and urethra. The kidneys filter waste from the blood and regulate fluid balance and electrolyte concentration. The nephron is the functional unit of the kidney, consisting of a glomerulus and tubules. Urine is formed through filtration, reabsorption, and secretion in the nephron. The kidneys also regulate acid-base balance, extracellular fluid compositi...

This text discusses the special senses of hearing, taste, sight, and smell. For hearing, the outer, middle, and inner ear structures are described. The outer ear collects sounds waves and directs them to the middle ear, which contains small bones that transmit vibrations to the inner ear. The inner ear contains fluids and structures that transform sound vibrations into neural signals. The cochlea transforms vibrations into signals that travel along the vestibulocochlear nerve. For taste...

This text discusses the structure and function of the urinary system, specifically the kidneys. The kidneys are located retroperitoneally between the T12 and L3 vertebrae. They contain an outer renal cortex and inner renal medulla. The functional unit of the kidney is the nephron, which filters blood to form urine. Blood enters the glomerulus where glomerular filtration occurs, forming filtrate that contains water, solutes, and waste products. Most of the filtrate is reabsorbed in the proximal c...

This text discusses the digestive system. The liver produces bile which aids in digestion. Jaundice is a condition caused by bile salts and bile pigments entering the bloodstream. Peyer's patches are lymphatic tissue found in the small intestine. The human body has 32 baby teeth. Saliva begins starch digestion in the mouth. The small intestine is the major site of absorption. The pyloric sphincter controls the movement of food from the stomach to the small intestine. Rennin digests milk protein....

The text discusses the digestive system and body metabolism. It covers topics like the different parts of the digestive system, how digestion occurs, and the role of metabolism and nutrients. Some key points: • The digestive system consists of the gastrointestinal tract and accessory organs. The GI tract has four layers: mucosa, submucosa, muscularis externa, and serosa. • Digestion begins in the mouth with chewing and the action of salivary enzymes. Food then moves to the stomach thr...

This text discusses the digestive system, its organs, functions, and metabolism. The digestive system breaks down food into nutrients that can be absorbed and used by the body. It consists of the alimentary canal and accessory organs. The alimentary canal includes the mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus. Accessory organs like teeth, salivary glands, pancreas, liver, and gallbladder assist in digestion. The organs perform functions like ingestion, digest...

The text discusses the lymphatic system and immune response. Regarding the lymphatic system, key points include: • The lymphatic system is a one-way system that lacks arteries and begins with blind-ended lymph capillaries, whereas the blood vascular system is two-way. • Lymphatic vessels resemble veins as they are thin walled and have valves. Lymph capillaries differ in that they are more permeable and blind ended. • The lymphatic vessels function to pick up and return excess ti...

The text discusses the lymphatic system and immune response. Some key points: • Any substance that can provoke an immune response is called an antigen. • The thymus gland is larger in younger people and found in the anterior thorax. • Cytokines are proteins secreted by macrophages that are important in the immune response. • Antibodies are not part of the first line of defense against pathogens. • When exposed to the wrong blood type for the first time, a person...

The text discusses various aspects of blood, including the different blood cell types and their functions. Some key points are: • Neutrophils, eosinophils, and basophils are types of granulocytes. • An abnormally low white blood cell count is called leukopenia. • Hematocrit is a measurement of the percentage of erythrocytes in blood volume. • A thrombus that breaks away and floats freely in the bloodstream is called an embolus. • The average healthy male has 5 quart...

The text discusses the blood vessels of the pulmonary and systemic circulations, their structures, classifications, functions and related physiology. Key points: The pulmonary blood vessels carry oxygen-depleted blood to the lungs and return oxygenated blood to the heart. The systemic circulation includes arteries carrying oxygenated blood away from the heart and veins carrying deoxygenated blood back to the heart. Blood vessels are classified based on their sizes and location. Arteries...

The endocrine system consists of glands that secrete hormones directly into the bloodstream to regulate various bodily functions. The endocrine glands include the pituitary, thyroid, parathyroid, adrenal, pineal, thymus, pancreas and gonads. Hormones act on target cells by either directly activating genes or utilizing a second messenger system. Hormone release is regulated mostly by negative feedback mechanisms. The pituitary gland is considered the "master gland" as it controls the activities ...

This text discusses the anatomy and physiology of the special senses, focusing on the eye, ear, taste, and smell. Key topics covered include: The structures of the eye including the cornea, lens, retina, optic nerve, eyelids, conjunctiva, lacrimal apparatus, and extrinsic eye muscles. The eye contains fluids like the aqueous humor and vitreous humor. The pathway of light through the eye and how vision is achieved is described. Conditions like myopia, hyperopia, astigmatism, and cataracts are ...