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A & P Study Guide for Exam 1

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A & P Study Guide for Exam 1
BIOL 111 Test 1 Study Guide
Please note that this is just a guide to help you with your studies. There might be additional information that was talked about in class that is not on this guide.
Chap 1
Definitions of
Homeostasis - ability to maintain relatively stable internal conditions even though the outside world changes continuously; maintaining the internal environment within physiological units
External stimuli – intense heat or cold
Internal stimuli – psychological stresses, exercise
Physiology - science of body functions at many levels;
Anatomy – science of structure; relationships revealed by dissection (cutting apart)
Levels of organization
Atoms – Molecule (Chemical level) – Cells (Cellular level) – Tissues (smooth, connective, epithelial) – Organs – Organ System – Organism
A basic understanding of the different systems, what they do and which organs are apart of each. (See slides)
Organ system interrelationships
All cells depend on organ systems to meet their survival needs; Organ systems work cooperatively to perform necessary life functions
Necessary life functions
Maintaining boundaries between internal and external environments, movement (contractility), responsiveness, digestion, metabolism (cata and ana), excretion, reproduction, growth
Survival needs
Nutrients, oxygen, water, normal body temperature, appropriate atmospheric pressure
Components of a control mechanism
Receptor (sensor) – monitors the environment; responds to stimuli
Control center (brain) – determines the set point at which variable is maintained; receives input; determines response
Effector – receives output from brain; provides the mean to respond; response acts to reduce or enhance stimulus (fb)
Negative feedback VS positive feedback
Negative – response reduces/shuts off original stimulus e.g. regulation of body temp/blood volume by ADH
Positive – response enhances/exaggerates the orig. stimulus e.g. blood clotting, labor contractions by oxytocin
Anatomical position, regions, planes, cavities, directions and orientations
Sagittal – vertically left and right
Midsagittal – lies on midline
Parasagittal – not on midline
Frontal/Coronal – anterior and posterior (front and back)
Transverse – superior and inferior (north and south); produces cross section
Oblique – cuts made diagonally
Regions: Axial (head, neck, and trunk) and Appendicular (limbs)
Serous membrane – thin double-layered membrane separated by serous fluid
Parietal serosa – lines internal body walls
Visceral serosa – covers the internal organs

Chap 2
Definitions of
Matter – anything that occupies space and has mass
States: solid, liquid, gas
Energy
Types (KE and PE) and forms (electrical, mechanical, chemical, heat)
Chemistry
Weight – force of gravity acting on a mass
Mass – amount of substance matter contains
Atoms
Atomic # - # of protons in nucleus
Mass # - mass of the protons and neutrons
Atomic weight = protons + neutrons
Nucleus = protons and neutrons
Isotopes – structural variations of elements that differ in the number of neutrons they contain
Elements found in the body - C, H, N, O (96%)
Atomic structure – determined by numbers of subatomic particles; nucleus consists of neutrons and protons
Valence Shells and how many electrons each of the first three shells can hold and prefers
1st shell 2e-, 2nd shell 8e-, 3rd shell 18e-
How this affects bonding and reactivity
Different types of bonding
Covalent – sharing of e-
Ionic – transfer of e-
Hydrogen – sharing of hydrogen
Which bonds give water its unique properties – hydrogen bonds (surface tension)
Chemical reactions—formation of or breaking of bonds between atoms (involve energy); usu. reversible
Types
Synthesis reaction – reactants are combined to synthesize product A+B->C, endergonic, anabolic
Decomposition – reactants are broken down into smaller particles AB -> A+B, catabolic, exergonic
Properties – (exergonic – release energy e.g. catabolic reactions; endergonic – products contain more PE than did reactants e.g. anabolic reactions)
Catalysts – (increase rate without being chemically changed e.g. enzymes), etc…
Solution concentrations and types
Solution – solute particles are very tiny, do not settle out or scatter light e.g. mineral water;
Colloid – solute particles are larger than in a solution and scatter light, do not settle out e.g. gelatin;
Suspension – solute particles are very large, settle out, and may scatter light e.g. blood)
Organic VS inorganic compounds
Organic contains carbon, usu. large and covalently bonded e.g. carbohydrates, fats, proteins, and nucleic acids;
Inorganic compounds do not contain carbon, e.g. water, salts and many acids and bases
Acids VS bases VS salts
Acids dissociate into H+ and one or more anions (proton donor);
Bases dissociate into OH- and one or more cations (proton acceptor);
Salts dissociate into anions and cations, none of which are either H+ or OH- pH scale
What regulates pH in body
Kidneys, lungs, and buffers
For each organic molecule (carbohydrates, lipids, proteins, and nucleic acids), know what is:
Monomer unit
Polymer types
Structure (elements, functional groups, etc?)
Function
Carbohydrates
Monosaccharides – simple sugars (glucose, fructose, galactose, deoxyribose, ribose)
Disaccharides – two linked mono (sucrose, maltose, lactose)
Polysaccharides – chains of mono (glycogen)
Used for energy and structural support and ribose sugar in DNA
C chain with H and OH side groups (C, H, O)
Lipids
Mostly C chains with H side groups (C, H), nonpolar
Used for energy, storage, messengers, protection, support
Triglycerides – saturated vs unsaturated
Phospholipids – cell membrane
Steroid – hormones, cholesterol
Proteins
Made of long chain of amino acids (C, H, N, O)
20 different amino acids structural, enzymatic, regulatory sensitive to pH and high temp primary, secondary, tertiary, quarternary
Nucleic Acid
Store genetic info (DNA and RNA); C, H, N, O, P
Monomer unit: nucleotides

Chap 3
Plasma membrane – composed of membrane lipids, proteins, and carbohydrates; integral – transport VS peripheral - structural
Function – allows for a semi-permeable membrane
Passive VS active transport - passive – no energy; active – requires energy
Passive Subtypes
Simple Diffusion (KE) – e.g. movement of O2 through phospholipid bilayer
Facilitated Diffusion (KE) – e.g. movement of glucose into cells
Osmosis (KE) – e.g. movement/diffusion of H2O through phospholipid bilayer
Active Subtypes
Primary Active Transport - e.g. pumping of ions across membranes
Secondary (Ions) – e.g. movements of polar or charged solutes across membranes
Exocytosis – e.g. secretion of hormones and neurotransmitters
Phagocytosis (endocytosis)– e.g. WBC phagocytosis – “cell eating”
Pinocytosis (endocytosis) – e.g. absorption of intestinal cells – “cell drinking”
Which types of molecules go through with each type
Can pass: gases (CO2, O2), hydrophobic molecules (benzene), small polar molecules (H2O, ethanol)
Cannot pass: large polar molecules (glucose), charged molecules (amino acids)
Energy type
How tonicity influences cell – measure of a solution’s ability to change the volume of cells by altering their water concentration
Function of organelles
Mitochondria – site of ATP synthesis; powerhouse of the cell
Ribosomes – site of protein synthesis
Rough ER – modify proteins after they are made and transport to Golgi and other sites
Smooth ER – lipid synthesis, detoxification of drugs, glycogen breakdown
Golgi Apparatus – protein sorting and packaging, “post office”
Lysosomes – contains hydrolases that digest intracellular debris; garbage disposal of cell
Vesicles –
Cytoskeletal organelles: network of rods in cytosol that support for cellular structure
Microfilaments – actins, movements within the cell
Intermediate Filaments – tensile strength, “guy wires”
Microtubules – tubulin, act to give cell a shape; hold organelles in place
Cellular extensions – protruding parts for motility or to increase surface area
Flagellum – used to propel a cell
Microvilli – used to absorb things
Function of the different membrane junctions
Tight Junctions – prevents fluid and most molecules from moving between cells
Desmosomes – bind adjacent cells together and reduce tension in fibers
Gap Junctions – allows ion and small molecules to pass from one cell to the next for intercellular communication
Nucleus—structure, functions and features 1. protein synthesis 2. DNA replication
Different phases of cell cycle and what goes on during each
Interphase
G1 (gap) – most of life metabolic functions
S (synthesis) – DNA replication and growth
G2 – proteins and enzymes being developed, preparation for division
Mitotic Phase (PMAT)
Prophase – chromosomes become visible, each with two chromatids joined at a centromere; centrosomes separate and migrate towards opposite poles; mitotic spindles and asters form
Kinetochore microtubules attach to kinetochore of centromeres and draw them toward the equator of the cell
Metaphase – centromeres of chromosomes aligned at the equator (metaphase plate)
Anaphase – centromeres of chromosomes split simultaneously—each chromatid now becomes a chromosome; chromosomes (V-shaped) are pulled towards poles by motor proteins of kinetochores
Telophase – two sets of chromosomes uncoil to form chromatin; new nuclear membrane forms around each chromatin mass; nucleoli reappear; spindle disappears
Cytokinesis – separation of cytosol; late anaphase; two daughter cells are pinched apart each containing a nucleus identical to the original
DNA replication
The different enzymes and what each does
Helicase – unwinds the double helix and exposes the bases
DNA polymerase "walks" down the DNA strands and adds new nucleotides to each strand. The nucleotides pair with the complementary nucleotides on the existing stand (A with T, G with C). Functions in 5’ to 3’ direction.
Leading VS lagging strands
Leading strand – first strand which replicates nucleotides one by one
Lagging strand – other strand which replicates in chunks
Replication fork – replication origin forming a Y shape
Nucleotides-Gs and Cs; Ts and As
Semi-conservative process – using the old DNA as a template to make 2 new DNA; DNA will consist of 1 old and 1 new strand
Central dogma of protein synthesis – DNA -> RNA -> Protein; describes how DNA genes become proteins
Different types of RNA and their roles
Differences from DNA
Exons vs introns
Exons get expressed in mRNA; introns get spliced out “junk DNA”
Transcription – DNA -> mRNA
Enzymes involved – RNA polymerase
Where it takes place - nucleus
How it happens – begins at promoter sequence where RNA polymerase attaches, and ends when it reaches terminator sequence
End product – pre-mRNA and mRNA
Codons – each three-base sequence on DNA
Translation – mRNA -> polypeptide
Where it takes place – ribosome in the cytoplasm
How it happens –sequence of nucleotides on mRNA is read by rRNA to construct a protein with codons
End product – polypeptides/proteins
The fate of the protein that was made - specific tRNA molecule carries specific amino acids; anticodons on tRNA are matched to specific codons on mRNA so proper amino acids can be strung together to create a protein molecule mRNA is identical to coding strand; template strand is used as a guide (“complimentary to mRNA”)

Chap 4
The four different types of tissue – epithelial tissue, nervous, connective, muscle
Epithelial tissue
Functions – protection, filtration, lubrication, secretion, digestion, absorption, etc
Types and samples of each
Covering and lining
Glandular (goblet cells)
General features
Closely packed cells with little extracellular material; many cell junctions often provide secure attachment
Cells sit on basement membrane
Apical (upper) free surface
Basal surface against the basement membrane
Avascular – nutrients and waste move by diffusion
Rapid cell division (high mitotic rate)
Cell type and layering on how these influence the tissue’s function
Examples of where each of these can be found
Simple squamous – diffuse and filter – air sacs of lungs
Simple cuboidal/columnar – secretion and absorption – kidney tubules, digestive tract, bronchi
Pseudostratified Columnar – secretion – trachea
Stratified squamous – protection – skin/epidermis
Transitional – Stretches readily – bladder
Endocrine vs exocrine glandular epithelial
Endocrine – ductless; secrete hormone that travel through lymph or blood
Exocrine – secrete products into ducts onto body surfaces (skin) or cavities e.g. mucus, sweat, oil, and salivary glands
Types of exocrine
Functional
merocrine – products are secreted by exocytosis (e.g. pancreas, sweat, salivary gland holocrine – products are secreted by rupture of gland cells (e.g. sebaceous gland)
Structural
Duct structure: Simple/compound
Secretory structure: tubular/alveolar
Connective tissue
Functions – bind and support, protection, insulation, transport
Types – connective tissue (proper), cartilage, bone, blood
General features
Occur between surfaces
Vascular
Cells (immature VS mature)
Immature (-blasts) – newly born cells that will develop to any kind of cell and becomes mature (-cytes)
Extracellular matrix – any part of an organism’s tissue that is located outside of the cells
Characteristics - nonliving
Ground substance – unstructured material (fluid, proteins); medium where nutrients can diffuse between blood capillaries and cells
Fibers – Collagen, elastic, reticular fibers
Collagen (white fibers) – strongest and most abundant type, provides high tensile strength
Elastic – networks of long, thin, elastin fibers that allow for stretch
Reticular – short, fine, highly branched collagenous fibers
Classes
Connective Tissue Proper
Loose
Loose Areolar – gel-like matrix – cushions – distributed under epithelia of the body
Loose Adipose – gel-like – great insulation and energy storage – under skin in hypodermis
L. Reticular – reticular fibers – stroma that support other cell types – lymphoid organs, spleen
Dense
Dense Regular – collagen fibers, few elastic fibers – tendons, ligaments
Dense Irregular – fibrous capsules surrounding joints
Dense Elastic – walls of arteries
Cartilage
Hyaline – forms costal cartilage of the ribs
Elastic – bendable, external ear (pinna – funnels the sound)
Fibrocartilage – absorbs shock – between vertebrae
Bone – osseous tissues – hard, calcified matrix, supports and protects, provides lever
Blood – RBC, WBC, platelets – transport of CO2 and O2, nutrients, wastes, and other substances
Nervous tissue
Functions and features – controls body functions, vascular, conduct nerve impulses, innervates most part
Types of cells
Neurons – branching with extensions – axons (sends signals), dendrites (receive signals)
Glia – smaller and may enwrap neurons – supporting (insulation, ion regulation, etc
Location – brain, spinal cord, nerves
Muscle tissue
Functions and features – moves body – vascular – innervated
Types of cells – skeletal, cardiac, smooth myocytes
Skeletal – striations, voluntary movement – facial expressions,
Cardiac – striated, branching, intercalated discs, only in heart - involuntary
Smooth – spindle-shaped – propel things throughout the body e.g. food in digestive tract - involuntary
Membranes
General features – incorporate one or more tissue types
Location
Cutaneous membrane – skin
Serous membrane – anchors organs to cavity walls, provides cushioning
Tissue repair: restoring homeostasis
Process and definition
1. Inflammation – WBC fights off bacteria; platelet clotting occurs forming scab (positive feedback)
2. Organization/granulation – Fibroblasts produce collagen w/c resist the tensile strength; granulation – tissues with tons of capillaries
3. Regeneration/fibrosis – epithelium thickens, forms scar tissues (collagen fibers are in a weave)

Integumentary System
Functions
Protection (from outside factors) – 3 types of barriers
Chemical – sweat, acidic, antibacterial chemicals
Physical/mechanical – desmosomes
Biological barriers – WBC/macrophages
Body temperature regulation – sweat, hair, top of head; vasodilation, vasoconstriction
Cutaneous sensations – temperature, touch, vibrations
Metabolic functions – Vitamin D
Blood Reservoir – 5% of total blood within Integumentary System
Excretion – waste through the skin (sweat), urea, (bacteria stinks in sweat)
Which parts of the integumentary are actively doing cell division?
Stratum basale/ germinativum (germinating layer) – epidermis - keratinocytes
The three major regions: epidermis, dermis, hypodermis
Epidermis – Keratinized stratified squamous epithelium
Cells
keratinocytes – produce keratin (allows skin to be tough) melanocytes – melanin (skin tone)
Epidermal dendritic (Langerhans) – macrophages that help activate immune system
Tactile (Merkel) cells – touch receptors – sense light
Layers: Deepest has highest metabolic act, as it goes up it has less metabolic act slowly dying (dead cells)
Stratum corneum – most superficial; 20-30 layers of dead cells; filled with keratin, waterproof
Stratum granulosum – granule layer (dying)
Stratum spinosum – spiny; layers of keratinocytes unified by desmosomes; cells contain intermediate filaments
Stratum basale – deepest epidermal; basement; mitotic stem cells
Stratum Lucidum – between granulosum & corneum – in thick skin only, palms and feet
Dermis – strong, flexible connective tissue [vascular – epidermis (avascular) relies for nutrients]
Cells include fibroblasts, macrophages, mast cells, and WBC’s
Layers
Papillary – nipple-like; Meissner’s corpuscles – deeper touch; Free nerve endings – light touch; Fingerprints – epidermal ridges to form friction
Reticular layer – collagen fibers and elastic (stretch-recoil)
Cleavage lines
What forms them and why incisions are made along them?
Collagen fibers arranged in bundles form cleavage (tension) lines; incisions made parallel to heal more readily
Skin pigmentation
Three pigments contribute to skin color: melanin (melanocytes), carotene, hemoglobin
Appendages of the skin (Details such as functions and where they are located)
Sweat Glands
Eccrine (merocrine) – palms, soles, forehead; sweat: 99% H2O, NaCl, Vit C, antibodies, dermcidin (anti-bacterial chemical), metabolic wastes (urea); functions in thermoregulation
Apocrine – axillary and anogenital; sebum, ducts connect to hair, onset after puberty, cerumen/ear wax
Hair
Guarding against abrasion, distributed entire surface except palms, etc
Consists of dead keratinized cells; gray white hair: decreased melanin production
Hair Follicle
Extends from the epidermal surface into dermis; hair bulb – dermis, hair matrix – cells that divide/alive
Root hair plexus – sensory nerve endings/goose bumps (thermoregulation for animals)
Nail
Scalelike modification of epidermis; nail matrix – alive portion of the nail, rest are dead
Three types of skin cancer and treatments
Basal cell carcinoma – least malignant, most common; stratum basale multiplies, cured by surgical excision 99%
Squamous cell carcinoma – 2nd most common, radiation therapy or surgically removed, stratum spinosum, scalp
Melanoma – most dangerous, involves melanocytes, metastatic, treated by surgical excision w/ immunotherapy

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