Biology Basics & The Integumentary System PDF

BIOLOGY BASICS & THE I N T E G U M E N TA R Y SYSTEM H O W T O C A R RY A S C O P E C A L C U L AT I N G M A G N I F I C AT I O N  Center the slide over the light so that you can see the light shining through your sample. Set it to the lowest light that you can see at. Start with the scann...

BIOLOGY BASICS & THE I N T E G U M E N TA R Y SYSTEM H O W T O C A R RY A S C O P E C A L C U L AT I N G M A G N I F I C AT I O N  Center the slide over the light so that you can see the light shining through your sample. Set it to the lowest light that you can see at. Start with the scanning lens (short red objective lens). Bring the stage all the way up, then slowly move it down with the coarse focus adjuster until it is in focus. Fine tune it with the fine focus adjuster. Find your structure that you want to view more clearly Switch to 10x lens. Use the fine focus adjuster to get a clearer image. Switch to 40x lens. Use the fine focus adjuster, the diaphragm condenser, AND the brightness control to get a clearer image. You may need more light with this lens. If you lose your way, start over at the very beginning. S T E P S T O A L W AY S F I N D Y O U R F O C U S THESE ARE NOT THE SAMPLES YO U ARE LOOKING FOR MICROSCOPE NOPES Never use the coarse focus adjuster with the 10x or the 40x objectives. ONLY use it with the scanning lens Do not place or remove a slide until the scanning lens is in place. Do not carry the microscope with one hand Do not use the 100x oil immersion lens W H AT I S A C E L L ? The functional, structural biological unit, AKA the building blocks of life Two types: Prokaryotic: pro = before, karyote = cell No defined nucleus, circular, unbound DNA Bacteria Eukaryotic: eu = new, karyote = cell Contains a defined nucleus with long strands of bound and organized DNA Protists, fungi, plants, and animals CELL STRUCTURE: PLASMA MEMBRANE Envelops cell contents Barrier to outside Composed of a phospholipid bilayer that allows active and passive transport (like osmosis!) of molecules and ions into and out of cell CELL STRUCTURE: CYTOPLASM Cytosol: fluid inside cell that surrounds all organelles and in which most cellular activity occurs Organelles: cell “organs” CELL STRUCTURE: NUCLEUS Control center of cell, contains genetic material (DNA) Nuclear Membrane envelops the genetic material and nucleolus Nucleolus produces ribosomes Chromatin and DNA condense to form chromosomes during cell replication and division  CELL STRUCTURE: ER AND RIBOSOMES Endoplasmic Reticulum (ER): a series of tubes used for lipid synthesis, which are sometimes connected to ribosomes Ribosomes: mRNA is translated into proteins here, found both free- floating and attached to ER Rough ER: Contains ribosomes Smooth ER: No ribosomes CELL STRUCTURE: OTHER ORGANELLES Golgi Apparatus: “Amazon of the Cell” Packages proteins for transport out of or around cell Mitochondria: “Powerhouse of the Cell” Turns nutrients into ATP (energy battery packs for chemical reactions) Lysosomes: Breaks down waste Cytoskeleton: Maintains cell structure W H AT A R E G E N E S M A D E OF? HOW DO GENES WORK? THE CELL C YC L E S O M AT I C CELL DIVISION MITOSIS UNDER THE MICROSCOPE TISSUES Tissue: a combination of similar cells that are grouped together to perform a particular function Different tissues provide different functions such as protection, secretion, contraction, or transmission of nerve impulses Histology: “hist” = tissue, “ology” = study of We use a microscope to observe and study the different types of tissues 4 BASIC TISSUE TYPES Epithelial Connective Muscle Nervous EPITHELIAL TISSUE Epi = on top, thelium = cell layer Found on the outer or inner edge of other tissues Functions: cover the surface of other tissues, form the lining of body cavities and glands The only tissue capable of secretion (release of fluids or other useful substances) No blood supply, but does has nerve supply Highly regenerative to maintain protection Composed of only cells, which are packed closely together Consists of a free (apical) end and a basal surface attached to connective tissue Several types of epithelium that are classified according to shape and layers present  Transitional CLASSIFYING EPITHELIUM Transitional epithelium BASED ON SHAPE A N D L AY E R I N G CONNECTIVE TISSUE Most abundant and diverse tissue type in the body Functions: support, protection, binding, and insulation Made up of few cells that are surrounded by a nonliving extracellular matrix containing ground substance and/ or fibers Usually vascular and good nerve supply(besides cartilage) Classified according to the type and structure of matrix M AT R I X T Y P E S Collagen: Tough, stains smooth Fiber Types Elastin: Stretches, stains dark purple Reticular: Branching collagen that forms a network, stains smooth Ground Interstitial fluid Substance Proteins Types Minerals  Areolar Tissue Loose Adipose Tissue Reticular Tissue Proper Connective Tissue (Fibers Only) Dense Regular Connective Tissues Tissue Dense Irregular Dense Tissue Blood Elastic Tissue Fluid Connective Tissue (Ground Substance Only) Lymph Hyaline Cartilage Cartilage Elastic Cartilage Supportive Connective Fibrous or Tissue Fibrocartilage (Fibers + Ground Substance) Spongy Bone Bone Compact Bone Undifferentiated Mesenchyme Connective Tissue P RO P ER C ON N EC TIV E T IS S UE S (FIBE RS ONLY) Loose Areolar Adipose Reticular Dense Dense Regular Dense Irregular Dense Elastic SUPPORTIVE CONNECTIVE TISSUE ( F I B E R S + G RO U N D S U B S TA N C E ) Bone Spongy Bone Compact Bone Cartilage Hyaline Cartilage Fibrous or Fibrocartilage Elastic Cartilage OTHER CONNECTIVE TISSUES Lymphatic Fluid (fluid matrix) Blood (fluid matrix) Mesenchyme (undifferentiated)  Specialized tissue for MUSCLE TISSUE contraction Cells contain protein filaments of myosin and actin Function: causes the movement of structures in the body and regulates internal temperature Three types: Smooth Skeletal Cardiac N E RVO U S T I S S U E A highly specialized tissue that can conduct electricity extremely well. Function: conducts nerve impulses Both neurons and neuroglial cells PLEASE PUT YOUR MICROSCOPE A W AY P R O P E R L Y ! Make sure the stage is down and the scanning lens is rotated into place Wrap and secure the cord The eyepieces should be turned away from the stage The cover should be pulled down fully The microscope should be placed into the properly labeled spot in the cabinet The stage should be facing in, while the eyepieces and arm of the scope face towards the door What the IA sees What the student sees Pink circle Pink circle Pink circle Pink circle  V O C A B U L A RY Solvent- dissolves a Solute- the substance Solution- formed when solute being dissolved in a a solute is dissolved in a solvent solvent Ex. Water Ex. Sugar Ex. Simple Syrup  The passive transport of solutes from an area of high concentration to an area of low DIFFUSION concentration Passive transport does not require ATP (battery pack molecules)  Passive transport of water (solvent) across a selectively permeable membrane to an area of the solvent’s high OSMOSIS concentration to solvent’s low concentration, Ex. Water molecules moving across a cell membrane TONICITY When comparing two different solutions, we use tonicity. Hypotonic (hypo- = less than; -tonos = stretching) the solution with less solutes (causes hydrolysis) Isotonic (iso- = same) both solutions have the same amount of solutes Hypertonic solution (hyper- = more than) the solution with more solutes (causes crenation) **When talking about cells, we always describe the solution outside of the cell.** T H E I N T E G U M E N TA RY S Y S T E M (inte = whole, gument = body covering) Made up of the skin, hair, nails, sweat glands, and sebaceous glands Provides a protective barrier for the body, contains cutaneous sensory receptors, aids in the production of vitamin D, is important in regulating body temperature, and plays a minor role in excretion and absorption SKIN Did you know that the skin is the largest organ of the body? Functions: protective covering for deeper tissue, aids in regulating temperature, houses sensory receptors, synthesizes glandular chemicals, and excretes waste The skin is divided into two regions: Epidermis: epi = on top, dermis = skin Outermost layer that’s composed primarily of stratified squamous epithelium Dermis: inner layer of skin composed of connective tissues that support accessory structures such as hair, sweat glands, etc. Hypodermis: AKA subcutaneous fascia, layer sitting just below the dermis; most of the body’s fat is stored here HUMAN SKIN MODEL K E R AT I N A N D MELANIN Keratin: a protein that is very tough that is found in skin, hair, and nails In skin, it will be held in specialized cells called keratinocytes, found at the very top of the skin. Build up of these cells is very important for the palms of your hands and soles of your feet Melanin: a protein that is difficult for light to pass through, and is found in ALL skin, hair, and eyes (except for in the case of albinism) Melanin is held in specialized cells, called melanocytes, which are found in the lower-most level of the epidermis The amount of melanin present in the melanocytes is determined primarily by genetics, but can be deposited over time with sun exposure (tanning) The differences in amount of melanin present in hair, skin, and nails is what will determine what color those structures appear TAT T O O S During tattooing, dye is injected into the dermis of the skin There, it gets eaten by special cells (called macrophages: macro = large, phage = to eat) that are designed to pick up foreign invaders The macrophages then sit under the skin with the dye inside of them, making the image permanent Extracellular deposits of pigment are also found between collagen bundles As time goes on, breakdown of the ink, the macrophage, the build up of new skin pigment (melanin) overtop, and skin stretching will fade or warp the image over time. Sun exposure causes oxidization of the ink, making it to break down faster, as well as causing more melanin to be deposited. Therefore, wearing sunscreen on your tattoos is extremely important for their longevity. Sun exposure is the biggest threat to tattoos, even more than skin stretching. Complications include infections introduced at time of tattooing, allergic reactions to tattoo pigments, and photosensitivity reactions HAIR Made from dead keratinocytes Three layers: Cuticle: Thin protective outer layer. This contains the nourishing portion that is necessary for hair growth. The cells here are scale shaped and overlap, making it easy to damage this layer. Cortex: made of long keratin chains that add elasticity, suppleness, and resistance. Medulla: innermost layer that is soft and oily. A medulla layer will only be found in thick, wiry hairs THE NAILS Made from dead keratinocytes Located at the distal end of the fingers and toes (digits) Function: protect the fingers and grip and manipulate objects Composed of a free edge, body, and root Eponychium: cuticle  Fingerprints develop in the 3rd FINGERPRINTS and 4th month of fetal development The ridge arrangement on every finger of every human being is unique and does not alter with growth or age Superficial injuries do not affect the ridge, and the original pattern is duplicated in any new skin. An injury that destroys the dermal papillae, however, will permanently destroy the ridges.