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Medical Terminology: Prefix – word elements that are attached at the beginning of words to modify their meaning but cannot stand alone eg. ‘a’ without Word Root – basic meaningful parts of a term, cannot be broken down into another term with another definition eg. ‘kinein’ movement Suffix – word ele...

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Physiology Essentials 100 – BIOL 1051 Medical Terminology: Prefix – word elements that are attached at the beginning of words to modify their meaning but cannot stand alone eg. ‘a’ without Word Root – basic meaningful parts of a term, cannot be broken down into another term with another definition eg. ‘kinein’ movement Suffix – word elements or letters added to the end of a word or word part to form another term eg. ‘ia’ state or condition Akinesia (A-kines-ia) a condition without movement Anatomical Terminology: Superior – above Inferior – below Medial – toward midline Lateral – away from midline Proximal – towards point of attachment of a limb to the trunk Distal – away from point of attachment of a limb to the trunk Superficial – near surface Deep – far from surface Posterior – back surface Anterior – front surface Dorsal – back Ventral – belly Caudal – toward the tail Frontal/Coronal Plane – split front and back (anterior, posterior) Sagittal Plane – split left and right (through medial line) Transverse Plane – horizontal Body Cavities: • Closed, fluid-filled cavities that contain organs of the trunk • Protect organs • Permit changes in organ shape • Organs enclosed by these cavities are viscera Organ Systems: Integumentary system skin, hair, sweat glands, nails • Functions – protect against environment hazards and help regulate body temperature Skeletal system – bones, cartilage, ligaments • Functions – provide support and protection for other tissues, store calcium and other minerals and form blood cells Muscular system – skeletal muscles and tendons • Functions – movement, protection and support for other tissues and muscle contraction generates heat

Summary Pages Nervous system – brain, spinal cord, peripheral nerves, sense organs • Functions – direct immediate responses to stimuli, coordinate or moderate activities of other organ systems, provide and interpret sensory information about external and internal conditions and cognition and memory Respiratory system – nasal cavities, sinuses, larynx, trachea, bronchi, lungs, alveoli • Functions – deliver air to lung alveoli (where gas exchange occurs), provide oxygen to and remove carbon dioxide from, bloodstream, produce sounds for communication and facilitate odour detection Cardiovascular system – heart, blood, blood vessels • Functions – distribute blood cells, water, and dissolved substances (eg. Nutrients, waste products, oxygen and carbon dioxide) and distribute heat and assist in maintenance of body temperature Lymphatic system – spleen, thymus, lymphatic vessels, lymph nodes • Functions – defend against infection and disease and return tissue fluids to the bloodstream Endocrine system – pituitary gland, pancreas, gonads, thyroid gland, adrenal glands, endocrine tissues in other systems • Functions – direct long-term changes in the activities of other organ systems, adjust metabolic activity and energy use and control many structural and functional changes during development Digestive system – teeth, tongue, pharynx, esophagus, stomach, small and large intestine, liver, gallbladder, pancreas • Functions – process and digest food, absorb nutrients and conserves water and store energy sources Urinary system – kidneys, ureters, urinary bladder and urethra • Functions – excrete waste products from the blood, control water balance by regulating volume of urine produced, regulate blood ion concentrations and pH and help regulate blood pressure

Physiology Essentials 100 – BIOL 1051 Homeostasis (homeo = unchanging, stasis = standing) maintenances of a stable internal environment within a normal range (vital for organism survival). General Mechanisms Homeostat Homeostatic ic Regul Regulation ation Autoregulation – adjustment in response to a LOCAL environmental change. Extrinsic regulation – adjustment in response to an environmental change, results from activities of nervous and endocrine systems. Homeosta Homeostatic tic Regulatory Mechanism Mechanismss Receptor – detects stimulus or environmental change Control Centre – Receives and processes information from receptor, sends out commands Effector – Cell or organ that responds to the commands of the control centre and actively either opposes or enhances the stimulus Negative Feedback – Effector activates by control centre opposes (negates) the original stimulus. Counteracts or minimises a change (variation outside the set point triggers an automatic response that corrects the situation) (sustaining body temperature) Positive Feedback – Initial stimulus produces a response that amplifies or enhances the original change in conditions (occurs during childbirth with contractions) Maintenance of Homeostasis Requires the coordinated activity of multiple organ systems, eg. regulation of blood pressure involves cardiovascular, nervous, urinary and endocrine systems.

General Classes of Human Cells Sex Cells (germ or reproductive cells) – sperm and oocytes (eggs) Somatic Cells – everything else Plasma Membrane Structure – lipids, proteins, cholesterol and carbohydrates Function: • Physical barrier between intracellular and extracellular environment • Regulates exchange of molecules (selectively permeable) • Senses changes in extracellular environment • Structural support What is the phosphol phospholipid ipid bilayer? Part of the plasma membrane made of phospholipids which have hydrophilic heads (love water) and hydrophobic tails (hate water). The heads are in direct contact with the intra and extracellular environment, whereas the hydrophobic tails are in the middle. Its main function is to act as a barrier and allow selective passage of substances into and out of cells. Cytoplasm Consists of cytosol (intracellular fluid containing dissolved nutrients, ion, proteins and waste products), and organelles.

Summary Pages Organelles Microvilli • Increases surface area to facilitate absorption of extracellular materials Cytoskeleton • Strength and support movement of cellular structures and materials Cilia • Acts as a sensor, move materials over cell surfaces Mitochondria • Production of 95% of the cells ATP (energy) Ribosomes • Free – protein synthesis to be released into cytosol • Fixed – protein synthesis to pass through the rough endoplasmic reticulum Golgi Apparatus • Storage, alteration and packaging of secretory products and lysosomal enzymes Endopla Endoplasmic smic Reticulum • Synthesis of secretory products: intracellular transport and storage (synthesises lipids and carbohydrates) • Smooth – no fixed ribosomes, synthesises lipids and carbohydrates • Rough – fixed ribosomes on surface, contacts nuclear envelope, modifies/packages new proteins produced by fixed ribosomes Nucleus • Control metabolism, storage and processing of genetic information, control of protein synthesis Nucleic Acids Deoxyribonucleic Acid DNA pair of strands – encode information for building proteins and enzymes, controls cells structure and function and cellular metabolism Ribonucleic Acid RNA single strand – builds specific proteins using the information provided by DNA Gene • A section of a DNA strand that specifies the amino acids needed to produce a specific protein • Each gene comes in various forms called alleles • Resultant proteins give an organism its’ inherited features (eg. Eye colour) • Genetic code = the chemical language of cells Chromosome • A structure of nucleic acids and protein found in the nucleus (nucleosomes), carrying genetic information in the form of genes (tight coiled)

Physiology Essentials 100 – BIOL 1051

Summary Pages

Protein Synthesis TRANSCRIPTION (in the nucleus) 1. DNA helicase separates and unwinds DNA 2. Gene on DNA produces mRNA (the template for protein synthesis) TRANSLATION (in ribosomes) 1. mRNA exists nucleus through pores and enter ribosomes 2. tRNA molecule attaches specific anticodon to mRNA strand codons (complementary base pairing) 3 at a time 3. Amino acids create polypeptide chain then dissociated from ribosome (either into cytosol – free ribosomes, or into endoplasmic reticulum – fixed ribosomes) (ER modifies proteins + passes toward golgi apparatus – further packaged) One type of vesicle becomes lysosome, two others become secretory vesicles (fuse membrane and empty contents into extracellular space) or membrane renewal vesicles (add new proteins + lipids to plasma membrane) Transport Passive

Active

Diffusion – movement of substance from an area of high concentration to an area of low concentration (eg, gases oxygen, carbon dioxide and fatty acids). Active transport – proteins bind specific ions and carry them across the plasma membrane, against the concentration gradient via carriermediated transport (ATP is used).

Osmosis – Diffusion of water across a semipermeable membrane to remove concentration gradient between intracellular and extracellular environment.

Facilitated Diffusion – proteins bind specific ions and carry them across the plasma membrane down the concentration gradient via carriermediated/facilitated diffusion.

Exocytosis – Vesicle fuses with the plasma membrane to move substances out of the cell (ATP is used).

Endocytosis – Extracellular materials packaged in vesicles at the plasma membrane and transported into the cell (receptor mediated endocytosis = hormones, pinocytosis = nutrients “liquids”, phagocytosis = bacteria “solids”). (ATP is used)

Intercellular Comm Communication unication

Mitosis The main purpose of mitosis is for growth and to replace worn out cells. It happens in a series of steps Interphase – cell copies its DNA and grows in preparation for division Prophase – nuclear envelope breaks down, centrioles move to the opposite poles and spindle fibres form Metaphase – spindle fibres align chromosomes along the middle of the cell nucleus Anaphase – sister chromatids separate to opposite sides, spindle fibres retract Telophase – nuclear membranes begin to form, chromosomes begin to uncoil Cytokinesis – division of cytoplasm between two daughter cells occurs Meiosis I The first meiotic division is a reduction division (diploid → haploid) in which homologous chromosomes are separated PP-I: I: Chromosomes condense, nuclear membrane dissolves, homologous chromosomes form bivalents, crossing over occurs MM-I: I: Spindle fibres from opposing centrosomes connect to bivalents (at centromeres) and align them along the middle of the cell AA-I: I: Spindle fibres contract and split the bivalent, homologous chromosomes move to opposite poles of the cell TT-I: I: Chromosomes decondense, nuclear membrane may reform, cell divides (cytokinesis) to form two haploid daughter cells Meiosis II The second division separates sister chromatids (these chromatids may not be identical due to crossing over in prophase I) PP-II: II: Chromosomes condense, nuclear membrane dissolves, centrosomes move to opposite poles (perpendicular to before) MM-II: II: Spindle fibres from opposing centrosomes attach to chromosomes (at centromere) and align them along the cell equator A-II: Spindle fibres contract and separate the sister chromatids, chromatids (now called chromosomes) move to opposite poles TT-II: II: Chromosomes decondense, nuclear membrane reforms, cells divide (cytokinesis) to form four haploid daughter cells

Physiology Essentials 100 – BIOL 1051 Types of Tissue Connective tissue functions – fills internal spaces, provides structural support and protection for other tissues/organs, transports fluids and dissolved material within the body, store energy Epithelial tissue functions – provide physical protection, control permeability, aid sensation (nervous system function), produce specialised secretions Nervous tissue functions– receive stimuli and send the impulse to the spinal cord and brain, the brain sends back a response to the muscles via the nerves Muscle tissue functions – movement, maintenance of posture and body temperature, construction of organs and vessels, circulation of blood via heart contractions Connec Connective tive Tissue Consists of – specialised cells, extracellular protein fibres (collagen fibres, reticular fibres, or elastic fibres) and fluid called group substance Classification – connective tissue proper (loose or dense), fluid connective tissue, supporting connective tissue Epithelial Cells Classification: Primarily based on cell shape and the number of cell layers: Simple = single layer cells Stratified = several layers of cells Squamous = thin and flat shape Cuboidal = cube shape Columnar = column shape There are two parts to the name: first = number of cell layers, second = cell shape (eg. First = simple or stratified, second = squamous, cuboidal or columnar) • Simple squamous = secretions or absorption or diffusion, decrease friction (lining of body cavities and blood vessels) • Stratified squamous = protection (skin, lining of mouth) • Simple cuboidal = secretion and absorption (glands, ducts and kidney tubules) • Simple columnar = secretion, absorption, and limited protection via cilia (lining of stomach, intestines) • Stratified cuboidal = limited protection, secretion, absorption (rare) • Stratified columnar = protection (small areas of pharynx, epiglottis, anus, mammary glands, salivary gland ducts and urethra)

Summary Pages

Integumentary System Major Organs – skin, hair, sweat glands, nails Function – protects against environmental hazards, excretion of salt, water + organic wastes, maintenance of body temperature, synthesis of vitamin D Major Parts: • Cutaneous membrane/skin – epidermis = superficial epithelium and dermis = connective tissue • Accessory structures – hair, gland and nails Charac Characteristics teristics of: • Epidermis – consists of stratified squamous epithelium (protects dermis, prevents water loss, helps keep microorganisms outside the body), superficial cells are dead, avascular (lacks blood cells), nutrients and oxygen diffuse from capillaries in the dermis. Stratified squamous epithelium contains 2 cell types: o Keratinocytes – epithelial cells that contain keratin (protein) o Melanocytes – produce melanin (pigment that protects skin from UV radiation) • Dermis – contains capillaries, lymphatic vessels and sensory neurons that supply skin surface (bruise = rupture dermal blood vessels = blood leak into the dermis), contains collagen and elastic fibres that give dermis strength and elasticity (wrinkles decreased elastic fibres caused by aging, hormones + UV radiation)

Physiology Essentials 100 – BIOL 1051 Skeletal Systems Tissues Tissues that make up the skeletal system are; bone, cartilage and ligaments Type of connective tissue: • Connective tissue proper – ligament (dense) • Supportive connective tissue – bone and cartilage Bone Consists of – extracellular protein fibres, ground substance (fluid) and inorganic compounds (calcium) and 4 types of cells: • Osteocytes – mature bone cell that maintains bone matrix • Osteoblasts – immature bone cell that produces new bone matrix in a process called ‘ossification’ or ‘osteogenesis’ • Osteoclasts – absorb and remove bone matrix • Osteogenic – stem cells that ultimately become osteoblasts Compac Compactt Bone • Osteon (or Haversian system) – basic functional unit of mature compact bone, osteocytes are arranged in a concentric pattern • Lamellae – layers of bone matrix and collagen fibres that add strength and resiliency • Canaliculi – narrow passageways that permit transportation of nutrients and waste between osteocytes and blood vessels • Periosteum – membrane that covers superficial layer of compact bone, contains fibrous outer layer and cellular inner layer o Function: isolates from surrounding tissues, provides a strong anchor point for ligaments and tendons, provides a route for blood vessels and nerves, takes part in bone growth and repair • Endosteum – thin layer of osteogenic cells, osteoblasts and osteoclasts, covers trabeculae of spongy bone and line the medullary cavity o Function: bone growth, repair, and remodelling Spongy B Bone one • Trabeculae – meshwork of supporting bundles of fibres in the matrix of spongy bone, nutrients reach osteocytes by diffusion along canaliculi on the trabeculae • Bone marrow – within the epiphyses of long bones and large bones, red bone marrow (blood cell production) is present between trabeculae, yellow bone marrow (adipose tissue-energy reserve) is present at other sites Ossification Endochondral ossification – occurs in most bones (except clavicles, mandible, flat bones of the skull), and involves replacing hyaline cartilage with bone. Intramembranous ossification – occurs in clavicles, mandible and flat bones of the skull and begins when osteoblasts differentiate within mesenchymal or fibrous connective tissue.

Summary Pages Bone Growth and Maintenance Factors that affect growth and maintenance – Exercise, Nutrition and Hormones Exercise – increased physical activity, leads to increased applied force (stress) to bones, thus increasing bone production by osteoblasts. Decreased physical activity (bedridden) or weightless environment (using crutches), leads to decreased applied force to bones, thus bone loss (up to 1/3 of their mass). Homeostatic Regulation of Ca Calcium lcium Bone response: • to low calcium ion level in blood = osteoclasts stimulated to release stored calcium ions from bone, thus calcium released. • To high calcium ion level in blood = osteoclast activity decreases; osteoblast activity unaffected, thus calcium release slowed. Car Cartilage tilage Chondrocytes – the type of cell present in the matrix of cartilage (located in the lacunae) Articular cartilage – covers the bony surfaces in many joints as its shock absorbent (is a type of hyaline cartilage). Ligaments Collagen fibres – the most abundant type of fibre in ligaments, which are a bundle of subunits wound together like the strands of a rope, strong and flexible. Cells that maintain and produce collagen: • Fibroblasts – secrete protein subunits that interact in the matrix to form collagen • Fibrocytes – maintain collagen fibres

Physiology Essentials 100 – BIOL 1051 Neuron Neuronss • Cell body or soma – contains the cell nucleus • Dendrites – ‘dendrite’ is Greek for ‘tree’, receive information from other neurons (like an antennae) • Axon – carry information towards other neurons, length short 1m, start of axon: axon hillock, end of axon: axon terminals (site where axon passes information to other neurons • Synapse – site where neuron communicates with another neuron or cell, unidirectional (one-way) communication

Summary Pages Membr Membrane ane Potential Resting neuronal potential is -70 mV (it is the net charge of the inside of a neuron relative to outside the neuron. It is negative as the internal environment is primarily negatively charged and the external environment is primarily positively charged) • This is maintained by the sodium potassium exchange pump

Neuron C Classification lassification By Structure:

Neurog Neuroglia lia Role – to support and protect neurons

• • • •

By Function: • Sensory neurons - deliver information from sensory receptors in the body to the CNS • Motor neurons - carry movement instructions from CNS to the body • Interneurons - form connections only with other neurons (most common type)

Oligodendrocytes and Schwann Cells produce Myelin. Myelin is layers of membrane that insulates axons (myelin sheath). Myelin sheath is interrupted by gaps called nodes of Ranvier Myelin configuration increases speed of information transfer down axons

Physiology Essentials 100 – BIOL 1051 Graded Potential • Is a small, local, temporary change in the membrane potential (MP) caused by a stimulus • They can be depolarising (increase of positive ions in neuron) or hyperpolarising (increase of negative ions in neuron) (usually involve Na+, K+, or Cl−) • Caused by activation of chemically-gated, voltagegated and mechanically-gated (active) ion channels • When active channels open, change in MP only occurs locally – cannot affect entire cell

Action Pote Potential ntial (AP) • Voltage-gated Na+ and voltage-gated K+ channels are responsible for neuronal AP • If MP be...