Anatomy Exam 2

Explain how friction ridges are used in the identification of individuals.

They are unique to each individual and can be found on the tip of our fingers

List the different strata in the epidermis of thick skin vs. thin skin.

Thick skin- palm of hands, soles of feet; all five strata occur; houses sweat glands but no hair or sebaceous glands Thin skin- 4 layers, lacks stratum lucidum; contains follicles, oil and sweat glands

Define tonicity.

Tonicity is the ability of a solution to change the volume or pressure (ton) of the cell by osmosis.

List two steps of protein synthesis.

Transcription and translation

Define transcription and explain where it occurs in the cell.

Transcription is the formation of a ribonucleic acid (RNA) copy of a gene from DNA in the nucleus. Transcription includes three major events: initiation, elongation, and termination.

Describe the composition of cleavage lines.

"tension lines"; collagen and elastic fibers are oriented in parallel bundles in specific body locations; identifies the predominant orientation of collagen fiber bundles

Define apoptosis and give one example.

Apoptosis is the induced suicide of a cell. ex: the resorption of the tadpole tail at the time of its metamorphosis into a frog occurs by apoptosis

Define isotonic, hypertonic, and hypotonic solutions.

- An isotonic solution is one in which the solution and cytosol have the same relative concentration of solutes. (Ex: Saline with a 0.9% concentration of NaCl) - A hypertonic solution has a higher concentration of solutes and a lower concentration of water than the cytosol. Ex: a solution that contains 3% NaCl is hypertonic to red blood cells. - A hypotonic solution is one in which the solution has a lower concentration of solutes and there is a higher concentration of water than in the cytosol. (ex: pure water contains no solutes, so it is the most extreme example of a hypotonic solution.)

Define a codon and anticodon.

- Codon: a three nucleotide base unit. - Anticodon: a specific sequence of three adjacent nucleotides for each type of tRNA. The sequence of the anticodon determines the specific amino acid to which a given tRNA attaches. Additionally, the anticodon of each tRNA serves s the adapter site for binding a tRNA to its complementary codon of mRNA.

Describe the three fiber types in connective tissue.

- Collagen fibers: unbranched, cable-like long fibers that are strong, flexible, and resistant to stretching. They appear white in fresh tissue (or pink when stained). They are numerous in tendons and ligaments - Reticular fibers: similar to collagen but much thinner. They form branching, interwoven framework that is tough but flexible. They are abundant in stroma of organs such as lymph nodes, spleen, and liver. - Elastic fibers: contain protein elastin; they branch and rejoin, appearing wavy. They stretch and recoil easily; have a yellowish color. They are only visible in stained tissue (in which they appear black). They are abundant in skin arteries, lungs, allowing them to return to normal shape after being stretched

List the three categories of connective tissue.

- Connective tissue proper - supporting connective tissue - fluid connective tissue

Differentiate between exocrine and endocrine glands.

- Exocrine glands originate from invagination of epithelium that vurrows into the deeper connective tissues. These glands usually maintain their connection with the epitehlial surface by means of a duct, an epithelium-linee tube through which the gland secretions are discharged onto the epithelial surface. Ex: sweat glands, mammary glands, and salivary glands - Endocrine glands lack ducts and secrete their products (hormones) directly into the blood. Ex: thyroid and adrenal glands

Differentiate between endocytosis and exocytosis.

- Exocytosis is the movement of large substances FROM the cell. (Typically, when the vesicle and plasma membrane come in contact, the phospholipid molecules rearrange themselves and fuse. The fusion of the lipid bilayers requires the cell to expend energy in the form of ATP. - Endocytosis is the UPTAKE of large substances form the external environment into the cell.

Define the following terms: a. Hypertrophy, b. hyperplasia, c. atrophy, d. dysplasia, e. neoplasia.

- Hypertrophy: an increase in the size of the existing cells in a tissue, while the NUMBER of cells remains constant. - hyperplasia: an increase in the NUMBER of cells. (ex: callus) - atrophy: shrinkage of tissue by decrease in cell size or number. - dysplasia: abnormal tissue development - neoplasia: when tissue growth proceeds out of control and a tumor of abnormal tissue develops

Differentiate between integral and peripheral proteins.

- Integral proteins are embedded within and extend across the phospholipid bilayer; hydrophobic regions of the integral proteins interact wtih hydorphobic interior of the membrane. - Peripheral proteins are not embedded in the lipid bilayer. They are attached loosely to the external or internal surface and are "anchored" to the exposed part of the integral protein.

Differentiate between keratinized and nonkeratinized epithelium.

- Keratinized stratified squamous epithelium have a superficial layer that is dead. The cells fill with keratin as they move towards the apical surface, and in turn, die. - Nonkeratinized stratified squamous epithelium has a living superficial layer, with cells that lack keratin.

Classify and describe the various types of exocrine glands based on mode of secretion.

- Merocrine glands: package their secretion into secretory vesicles and release the secretion by exocytosis. The glandular cells remain intact and are not damaged in any way. Ex: lacrimal (tear) glands, salivery glands, exocrine glands of the pancreas and gastric glands of the stomach - Apocrine glands produce their secretion when the apical membrane around a portion of the glandular cell cytoplams with the secretory product pinches off and becomes the secretion. The glandular cell repairs the damange and then continues to produce new secretions. Ex: Mammary glands and ceruminous glands in the ear. - Holocrine glands form from cells that acculumate a product, and then the whole cell disintegrates. The ruptured, dead cell is then replaced by other epithelial cells undergoing cellular division. Ex: Sebaceous (oil) glands

List the two types of embryonic connective tissue.

- Mesenchyme embryonic tissue: is the source of all other connective tissue; has star-shaped (stallate) or spindle-shaped mesenchymal cells dispersed in a gel-like ground substance that contains fine, immature protein fibers. - Mucous connective tissue (also known as Wharton's Jelly); immature protein fibers in this tissue are more numerous than in mesechyme; only found in the umbilical cord.

Define mitosis and meiosis in cell division.

- Mitosis is the process of somatic cell division. - Meiosis is the process of sex cell division that results in four gametes

Identify the mode of secretion for salivary glands, sweat glands in axillary region, and oil producing sweat glands.

- salivary glands - merocrine - sweat glands in axillary region - merocrine - oil producing sweat glands - holocrine

List and define the four different types of body membranes.

- Mucous membrane (mucosa) lines passageways and compartments that eventually open to the external environment (including digestive, respiratory, urinary, and reproductive tracts); perform absorptive, protective, and secretory functions; formed by an epithelium layer and an underlying connective tissue called the lamina propria. - Serous membrane: lines body cavities that do not open to the external environment. Composed of simple squamous epithelium called mesothelium. Produces serous fluid. Serous membranes have two layers: parietal layer and visceral layer with a serous cavity between. Examples: pericaridum, pleura, and peritoneum. - Cutaneous membrane (aka: skin): covers the external surface of the body; composed of keratinized stratified squamous epithelium. Functions include preventing water loss and protecting internal organs. - Synovial membrane: composed of a superficial layer of squamous epithelial cells that lack a basement membrane and rest on an areolar connective tissue layer; secretes synovial fluid that reduces friction.

List the two cell types found in nervous tissue. & function

- Neurons: receive, transmit, and process nerve impulses - Glial cells: which do not transmit nerve impulses, but are responsible for protection, nourishment, and support of the neurons.

Define osmotic pressure and hydrostatic pressure.

- Osmotic pressure is the pressure exerted by the movement of water across a semipermeable membrane due to difference in solution concentration. - Hydrostatic pressure is the pressure exerted by a fluid on the inside wall of its container.

List and describe the three types of endocytosis.

- Phagocytosis (cellular eating) is when the cell engulfs or captures a large particle external to the cell by forming membrane extensions caleld pseudopodia. Once the particle is engulfed, it is enclosed within a membrane sac, which is later broken down chemnically after it fuses with a lysosome. Ex: when white blood cells engulf and digest a microbe. - Pinocytosis (cellular drinking) is when the cell internalizes droplets of interstitial fluid that contain dissolved solutes. Multiple, small vesicles are formed. The process is nonspecfic b/c all solutes dissolved within the droplet are taken into the cell. (Most cells perform this type of transport) - Receptor-mediated endocytosis is when receptors on the plasma membrane bind to molecules within the interstatial fluid and bring them into the cell. This enables the cell to obtain bulk quantities, even if they are in low concentration. Ex: transport of cholesterol from teh blood to a cell.

Describe the six functions of connective tissue.

- Physical protection (bones of the skull, thoracic cage, adipose connective tissue around the kidneys and eyes) - Support and structural framework (bones, cartilage, connective tissue to make capsules around organs) - Binding of structures (Ligaments bind bone to bone, tendons bind muscle to bone, and dense irregular connective tissue anchors skin to muscle and bone) - Storage (adipose is the major energy reserve; bone is the primary reservoir for calcium and phosphorus) - Transport (Blood carries nutrients, gases, and waste) - Immune protection (leukocytes in the tissues protect the body against disease; viscous nature of extracellular matrix restricts movement and spread of disease-causing organisms.

Name two different types of active transport.

- Primary active transport: Primary active transport uses energy derived directly from the breakdown of ATP. (This also provides the phosphate group that is added to the membrane transport pump, which results in a change in protein shape and the subsequent movement of a solute across the membrane.) - Secondary active transport (aka: cotransport or coupled transport) Secondary active transport (aka: cotransport or coupled transport) moves a substance against its own concentration gradient using energy provided by the movement of a second substance down its concentration gradient. (In other words, the kinetic energy of one substance moving down its concentration gradient provides the power to pump the other substance across its concentration gradient.) There are two kinds of secondary active transport: symport (2 substances moved in the same direction) and antiport (2 substances moved in opposite directions)

List and describe the four phases of mitosis.

- Prophase: chromosomes appear due to coiling of chromatin; nucleolus breaks down; spindle fibers begin to form from centrioles, which move to opposing cell poles; nuclear envelope breaks down at the end of this stage. - Metaphase: spindle fibers attach to the centromeres of the chromosomes extending from the centrioles; chromosomes are aligned at the equatorial plate of the cell by spindle fibers. - Anaphase: sister chromatids are separated by spindle fibers and mvoed to opposite ends of the cell; centromeres separate and each sister chromatid is now a chromosome with its own cantomere; cytokinesis begins. - Telophase: chromosomes uncoil to form chromatin; a nucleolus re-forms within each nucleus, spindle fibers break up and disappear; new nuclear envelope forms around each set of chromosomes; cytokinesis continues as cleavage furrow deepens.

Identify the cell types in connective tissue.

- Resident cells: stationary cells that are permanently housed w/in the connective tissue to help support, maintain and repair the extracellular matrix. Examples are fibroblasts, adipocytes, mesenchymal cells, and fixed macrophages. - Wandering cells continuously move throughout the connective tissue proper and are components of the immune system. Examples are mast cells, plasma cells, free macrophages, and other leukocytes.

Give an example of an epithelial tissue by combining the cell shape and arrangement.

- Simple squamous epithelium: single layer of thin, flat cells resembling irregular floor tiles w/ single nucleus bulging at center. Ex: air sacs in lungs, lining of lumen of blood vessels; serous membranes of body cavities - Simple cuboidal epithelium: single layer of cells about as tall as they are wide; spherical and centrally located nucleus. Ex: surface of ovary, kidney tubules; secretory regions and ducts of most glands. - Simple columnar epithelium: single layer of cells that ar etaller than they are wide. Nucelus is oval, oriented lengthwise and located int eh basal region of the cell. This cell type is ideal for secretory and absorptive functions. (Two types: ciliated and nonciliated) - Pseudostratified columnar epithelium: appears to be stratified due to irregular cell shape and size, but all cells are in direct contact with basement membrane. (Two types: cilated, which contains cilia on apical surface...typically secrete mucin, found in larger air passageways of the respiratory system, AND nonciliated, which do not contain cilia. Nonciliated form is very rare, occurs primarily in the male urethra and epididymis. ** See tissue table!!! **

Define the cleavage furrow and explain how it is involved in cytokinesis.

A cleavage furrow is where microfilament proteins on the inner surface of the cell pinch the mother cell into two separate cells. the cleavage furrow indicates where it is dividing.

Identify three different types of muscle tissue.

- Skeletal muscle: responsible for movement of the skeleton; composed of long, cylindrical cells called skeletal muscle fibers arranged in parallel bundles that runt he length of the entire muscle. The cells are multinucleated. Skeletal muscle is voluntary. It attaches to bone and sometimes skin - Cardiac muscle: confined to the thick middle layer of the heart wall (myocaridum); responsible for the contraction of the heart to pump blood. Made of short, bifurcating (branching) cells with one or two cenrally located nuclei. Cells are connected with intercalated discs. Cardiac muscles are involuntary. - Smooth muscle: lacks striations in othe rmuscleds; cells are fusiform (spindle-shaped), meaning they are thick in teh middle and tapered at the end. They rae short and contain one centrally loacted oval nucleus; found in the walls of most viscera, such as intestines, stomach, airways, urinary bladder, uterus, and blood vessels. Contraction helps move substances. Is involuntary.

Identify the epithelial tissue type on the following given organ, a. Skin, b. trachea, c. urinary bladder, d. air sacs in the lungs (alveoli), e. stomach, f. mouth and esophagus, g. kidney tubules.

- Skin: keratinized stratified squamous epithelium - Trachea: ciliated pseudostratified columnar epithelium - Urinary bladder: transitional epithelium - air sacs in the lungs (alveoli): simple squamous epithelium - stomach: nonciliated simple columnar epithelium - mouth and esophagus: nonkeratinized stratified squamouis epithelium - kidney tubules: simple cuboidal epithelium

Classify four different epithelial tissues by cell shape.

- Squamous cells are flat, wide, and somewhat irregular in shape; arranged like floor tiles w/ a nucleus that is somewhat flattened. - Cuboidal cells are about as tall as they are flat (though not a perfect cube since their edges are rounded); nucleus is spherical and located w/in the center of the cell - Columnar cells are slender and taller than they are wide; nucleus is oval and usually oriented lengthwise in the basal region of the cell - Transitional cells can readily change shape from polydedral to more flattened, depending on the degree to which the epithelium is stretched (such as in the lining of the bladder, which fills and is later emptied).

Differentiate among the three major types of membrane junctions and give one example for each type.

- Tight Junctions: composed of plasma membrane proteins that form strands or rows of proteins. They are poisitioned at apical surfaces around the cirucmference of adjacent cells to seal off the intercellular space and prevent substances from passing between cells; this requireds all materials to move THROUGH cells. Ex: tight junctions are present in epithelial cells that form the lining of the small intestine, so corrosive digestive enzymes do not move out and damage other cell types. - Desmosomes: composed of several proteins that bind neighboring cells. A thickened protein (protein plaque) is located ont eh internal surface of adjoining cells. Protein filaments extend from teh plaque through teh plasma membrane of both cells. Intermediate filaments of the cytoskelton extend throughout the cell to provide support and strength. Ex: The external layer of skin or heart. - Gap Junctions: composed of six transmembrane proteins called connexons, which form tiny fluid-filled tunnels or p9ores that extend cross a sall gap b/t adjacent cells. They rpovide a direct passageway for substances to travel b/t neibhoring cells (such as ions, glucose, and amino acids. Ex: Flow of ions b/t cells allows the spread of electrical activity in cardiac muscles of the heart.

Connective tissue proper

- bone: bone connective tissue - blood: fluid connective tissue - subcutaneous layer: adipose connective tissue - spleen: reticular connective tissue - tendons: dense regular connective tissue - elastic arteries: elastic connective tissue - tip of nose: hyaline supportin connect. tissue - external ear: elastic cartilage supporting connect. tissue - intevertebral discs: fibrocartilage supporting connective tissue - upper layer of dermis (Papillary layer): areolar connective tissue - lower layer of dermis (most of dermis): dense irregular connective tissue

Identify the connective tissue type on the following given organs:

- bone: bone connective tissue - blood: fluid connective tissue - subcutaneous layer: adipose connective tissue - spleen: reticular connective tissue - tendons: dense regular connective tissue - elastic arteries: elastic connective tissue - tip of nose: hyaline supportin connect. tissue - external ear: elastic cartilage supporting connect. tissue - intevertebral discs: fibrocartilage supporting connective tissue - upper layer of dermis (Papillary layer): areolar connective tissue - lower layer of dermis (most of dermis): dense irregular connective tissue

List the three types of RNA.

- messenger RNA (mRNA): carries the instructions for how to synthesis protein. - transfer RNA (tRNA): an adapter to bring a specific amino acid to a specific mRNA codon. - ribosomal RNA (rRNA): is the specific type of RNA for forming ribosomes.

Summarize the four stages involved in wound healing.

1)Cut blood vessels initiate bleeding into wound; brings clotting proteins and leukocytes 2)Blood clot forms; temporarily patching edges and acts as barrier 3)Cut vessels regenerate and grow in the wound - granulation tissue; production of new collagen; macrophage remove blood clot4)Epithelial regeneration of the epidermis

Briefly describe the characteristics of each layer of the epidermis.

1)Stratum basale- deepest layer; tightly attached to basement membrane; Keratinocytes, melanocytes, tactile cells (Merkelcells) 2)Stratum spinosum- once reached, new cell differentiates to a non-dividing, highly specialized keratinocyte; contains epidermal dendritic (Langerhans) cells 3)Stratum granulosum- granular layer; keratinization begins - fills up with protein keratin and cell's nucleus and organelles disintegrate 4)Stratum lucidum- dead cells; thin, translucent; pale and indistinct boundaries; keratinocytes are flattened and filled with translucent protein called eleidin5)Stratum corneum- dead cells; horn-like layer; most superficial layer; anucleate and tightly packed together

State the two types of facilitated diffusion and give one example for each.

1. Channel-mediated diffusion: the movement of small ions across the plasma membrane through water-filled protein channels. (The channel is either a leak channel (continuously open) or gated channel (opens in response to stimulus). Ex: Na+ leak channels allow Na+ to pass through continously. IN contrast, Na+ gated channels allow it to pass only in response to a particular neurotransmitter, such as in the use of muscle and nerve cells. 2. Carrier-mediated diffusion: the movement of small polar molecules, such as simple sugars or amino acids, which are assisted by carrier proteins. Ex: Glucose carriers are uniporters (only transport one substance) that prevent the loss of glucose in urine.

List the three general functions of a cell.

1. Maintain integrity and shape of a cell 2. Obtain nutrients and form chemical building blocks 3. Dispose of waste

Name the two major membrane transport processes.

1. Passive processes (which do not require cellular energy expenditure, but instead depend on the kinetic energy inherent within a substance as it moves down its concentration gradient). Ex: Diffusion and Osmosis 2. Active processes (require cells to expend energy, such as a substance being pumped up its concentration gradient or the release of a membrane-bound vesicle. Ex: Active transport and vesicular transport.

List the three different lipid components of the cell membrane.

1. Phospholipids - The majority of lipids are phospholipids. They have a "balloon" head (which is polar and hyrdophilic) and two tails, which are nonpolar and hydrophobic. 2. Cholesterol - scattered within the hydrophobic regions of the phospholipid bilayer; strengthens the membrance and stabilizes it at temperature extremes. 2. Glcyolipids - lipids with attached carbohydrate groups. They are on the outer layer of the phospholipid bilyaer, where they are exposed to interstitial fluid; together the carbohydrate portion of the glycolipid molecules and the glocoprotein molecules help form the glycocalyx (sugar layer) on the cell's surface. ** The lipid portion is insoluable in water. Creates a nonpolar boundary to most substances. (Only small, nonpolar substances can move through easily)

Name the three main parts of a eukaryotic cell.

1. Plasma membrane (outer limiting barrier separating the internal contents of the cell from the external environment) 2. Nucleus (largest structure within the cell and has a nuclear envelope; mostly made of genetic material) 3. Cytoplasm (general term used for all cellular contents located b/t plasma membrane and nucleus; includes cytosol, organells, and inclusions)

Name and describe the 4 types of non-membrane-bound organelles.

1. Ribosomes - organelles containing protein and ribonucleic acid (RNA), arranged into both a large and small subunit. Bound ribosomes are attached to the external surface of the rough ER (and used to synthesize proteins destined for export out of the cell). Free ribosomes are suspended within the cytosol. 2. Cytoskeleton: supports intracellular structural support, organization of organelles, cell division, and movement of materials. Is formed by a framework of fibrous proteins. The cytoskeleton is formed by microfilaments, intermediate filaments, and microtubules. 3. Centrosome: typically in close proximity to the nucleus; is pari of perpendicularly oriented cylindrical centriols, surrounded by an amorphous protein. The primary function i sorganizing microtubles within the cytoskeleton. Best known for its function in cellular division. 4. Proteasomes: Large, barrel-shaped protein complexes that are responsible for digesting organelles located within the cytosol and nucleus.

Briefly explain the following skin disorders: a. acne, b. psoriasis, c. basal cell carcinoma, d. malignant melanoma

Acne - plugged sebaceous ducts Psoriasis - autoimmune disease where T-lymphocyte attacks keratinocytes and overproduction occurs; patches of white scaly plaques basal cell carcinoma - orginates in stratum basale; central depression with pearly edge; most common and usually occurs in face malignant melanoma - aggressive growth and metastasis, arises from melanocytes (Asymmetry, Border is ragged, Color is not uniform, Diameter is growing, Evolving in size or shape)

Describe the six different functions of proteins in the cell membrane.

1. Transport proteins: provide a means of regulating the movement of substances across the plasma membrane. (Types of transport proteins include channels, carriers, pumps, symporters, and antiporters) 2. Cell surface receptors: bind specific molecules that are called ligands (ligands are molecules that bind to macromolecules). Ex: neurotransmitter released from a nerve cell that binds to cell surface receptor of a muscle cell to initiate contraction 3. Identity Markers: communicate to other cells that they belong to the body. (Cells of the immune system use identity markers to distinguish normal, healthy cells from foreign, damaged or infected cells) 4. Enzymes: may be attached to either internal or external surface of a cell of catalyzing chemical reactions. 5. Anchoring sites: secure the cytoskeleton to the plasma membrane 6. Cell-adhesion proteins: used for cell-to-cell attachments; proteins that form membrane junctions perform a number of functions, including binding cells to one another.

Describe the structure of a neuron.

A neuron has a cell body that houses both the nucleus and other organelles. Extending from the body are branches called nerve cell processes, called dendrites , that receive signals and transmit info to the cell body. The single long process extending from the cell body is an axon, which carries outgoing signals to other cells.

Briefly explain the following conditions: a. alopecia, b. male pattern baldness, c. hirsutism.

Alopecia- thinning of the hair male pattern baldness - hair loss only on the crown region of the skull; baldness allele is dominant gene; hirsutism- excessive male-pattern hairiness in face, chest, back; excess male hormone androgens

Differentiate between ciliated epithelium and nonciliated epithelium.

Both ciliated and nonciliated are forms of simple columnar epithelium. - Ciliated simple columnar epithelium has cilia that project from the apical surfaces of the cells. Muscus covers these apical surfaces and is moved along by the beating of the cilia. Ex: air passages in the lungs, uterine tubes. - Nonciliated simple columnar epithelium has no cilia, but often has microvilli. This type of cell lines most of the digestive tract, from the stomach to the anal canal.

Name the three basic components of connective tissue.

Cells, protein fibers and ground substance

Differentiate between chromatin and chromosomes.

Chromatin is the finely filamented mass of DNA and its associated proteins when a cell is NOT dividing. Chromatin becomes tightly coiled masses (Chromosomes) only when the cell is dividing.

Identify the differences between DNA and RNA in the sugar ring, nucleotide bases and the number of strands.

DNA - double strand, deoxyribose is the sugar, thymine is the 4th base. RNA - single strand, ribose is sugar, uracil is the 4th base.

Describe the structure of DNA and its function.

DNA is composed of deoxyribonucleotides, which include the five-carbon sugar dexyribose, a phosphate, and one of four nitrogenous bases: adenine, cytosine, guanine, and thymine. DNA is an enormous macromolecule that comprises most of the genetic material of the cell.

Name the major enzyme involved in DNA replication.

DNA polymerase

Describe the characteristics of simple diffusion.

Diffusion is the net movement of a substance from where it is more concentrated to where it is less concentrated, until equilibrium is reached. Examples of molecules that move by simple diffusion are respiratory gases (O2 and CO2), small nonpolar fatty acids, ethanol, and urea.

State what is produced during DNA replication.

During DNA replication, the 46 double helix strands are replicated.

Identify the layer of the skin into which a tattoo dye is injected, and explain why tattoos become permanent images on the skin.

Dye is injected into the dermis which doesn't have rapid cell turnover; scar tissue surrounds dye granules which are too big more dendritic cells to ingest; permanence

Describe how skin pigmentation is altered in albinism.

Enzyme (tyrosinase) needed to produce melanin is nonfunctional

List the two main layers of skin and name the layer below it.

Epidermis, dermis, subcutaneous layer

List the four main tissue types.

Epithelial- covers body and organ surfaces; lines cavities; forms glands Connective- binds; supports; protects tissues and organs Muscle- moves skeleton or organ walls Nervous- transmits nerve impulses and processes information

Distinguish between first-, second-, and third-degree burns.

First- redness, pain and edema; Second- blistered; Third- involves 3 layers

Explain the advantage of having friction ridges.

Formed from large folds and valleys of dermis and epidermis; help increase friction on contact so our hands can firmly grasp and feet do not slip; provides flexibility to skin

List and describe the events that occur during the three subphases of interphase.

G1 phase - cells grow and produce new organelles and structures required for DNA replication S phase (synthesis) - the 46 double helix strands are replicated G2 phase (second gap phase) - enzymes and other structures needed for CELL division are synthesized.

Define a gene.

Genes are the discrete units DNA is functionally organized into. Genes are segments of nucleotides within DNA that provice the instructions for the synthesis of specific proteins.

Define ground substance and List the three different large molecules found in ground substance.

Ground substance is a noncellular material produced by the connective tissue cells. It is within this substance that the connective tissue cells and protein fibers reside. (It can be viscous (blood), semisolid (cartilage), or solid (bone).) Three molecules in ground substance are: - Glycosaminoglycans (GAGs): polysaccharide composed of carbohydrate building blocks. They are negatively charged and hydrophillic - Proteoglycans: when a GAG is linked to a protein, forming an even larger molecule. Tehy are composed of carbohydrates. The size is largely due to the negative charge, which causes them to repel each other and spread out. - Adherent glycoproteins: proteins w/ carbohydrates attached, which act like glue to bond connective tissue cells and fibers to the ground substance.

Define tissue.

Groups of similar cells and extracellular material that perform a common function

Name the pigments that contribute to the normal skin color.

Hemoglobin, melanin and carotene(yellow-orange pigment)

Explain the change in size and shape of the red blood cell in different solutions related to the direction of water movement.

If red blood cells are in an isotonic solution, there will be no net movement of water, so the cells will maintain their normal shape. In a hypertonic solution, the solute concentration is higher than the cytosol, so there is less water in the solution and water will leave the cell (possibly causing crenation (when the cell shrinks). In a hypotonic solution, the solute concentration is lower than the cytosol, so there is more water in the solution and the water ENTERS the cell, which can cause the cell to lyse (or rupture) from the pressure.

Construct the mRNA sequence based on a given DNA template.

If the base sequence of DNA template strand is TTAGCTAGC, then the base sequence of the newly formed RNA will be AAUCGAUCG Base pairing: DNA RNA Thymine (T) --- (A) Adenine Adenine (A) --- (U) Uracil Cytosine (C) --- (G) Guanine Guanine (G) --- (C) Cytosine

Define introns and exons in the pre-mRNA.

Introns are noncoding regions of mRNA. Exons are the nucleotide sequences in the mRNA that were transcribed from DNA and are susequently spliced together.

Describe the functions of the five cell types (keratinocytes stem cell, melanocytes, nondividing keratinocytes, tactile cells, and Langerhans cell) in the epidermis.

Keratinocytes stem cell - divides to generate new cells in stratum basale Melanocyte - produce and store melanin Nondividing keratinocytes - highly specialized keratinocyte in stratum spinosum; attach to their neighbors by desmosomes Tactile ends - Merkel cells; release chemicals that stimulate sensory nerve endings when compressed Langerhands cell - immune cells that fight infection in epidermi

Name the three different types of hair.

Lanugo- fine, unpigmented, downy hair that appears on fetus Vellus- fine unpigmented/lightly pigmented hair; upper and lower limbs Terminal- coarser, pigmented, longer; grows on scalp, eyebrows, eyelashes, axillary and pubic

Briefly explain the 'rule of nines' that is used to estimate the surface area of a burn.

Major body parts account for 9% of total body surface area (head/neck, limb) 18% (legs, front or back trunk); 1% perineum

Name the type of RNA formed after completion of transcription.

Mature mRNA is formed at the completion of transcription.

Differentiate between the two common types of sweat glands (merocrine and apocrine).

Merocrine- eccrine; secretes to surface of epidermis; thermoregulation; eliminates drugs; prevents growth of microorganisms Apocrine- secretes to hair follicle; viscous and cloudy secretions; bacteria causes noticeable odor BOTH - myoepithelial cells contract to squeeze gland in response to nervous system stimulation

Briefly describe the structure of hair and nails.

Nails- scale-like modifications of the stratum corneum; eponychium - cuticle; hyponychium - free nail edge Hair- keratinized cells growing from follicles

Name the 5 types of membrane-bound organelles within a cell

Name the 5 types of membrane-bound organelles within a cell 1. Endoplasmic reticulum: an extensive interconnected membrane network that varies in shape but with one continous lumen. Two types: Rough ER (with ribosomes attached) and Smooth ER (without ribosomes attached) 2. Golgi apparatus: (several elongated flattened saclike membraneous structures called cisternae. The Golgi apparatus has distinct polarity, the cis-face (closer to ER) and trans-face. 3. Lysosomes: small, membraneous sacs that contain digestive enzymes which are immersed in acidic fluid (pH 5). Lysosomes participate in digestion of unwanted or uneeded substances, damaged organelles, etc. 4. Peroxisomes: membrane-enclosed sacs that contain over 50 enzymes that vary by cell type. They are responsible for removal of hydrogen from a molecule and the subsequent production of Hydrogen Peroxide. 5. Mitochondria: oblong-shaped organelles with double membrane with fold of the inner membrane called cristae. Mitochondria are the "powerhouses" of the cell, and engage in aerobic respiration to complete the digestion of glucose and other fuel molecules, such as fatty acids.

Describe the main characteristics of epithelial tissue.

One or more layers of closely packed cells; little to no extracellular matrix; polarity: Apicalsurface(free) and basalsurface(fixed); lack blood vessels; rich with nerves; high regeneration capacity

Define osmosis.

Osmosis is the passive movement of water through a selectively permeable membrane in response to a difference in relative concentration of water on either side. Osmosis is different from simple diffusion because it does not involve the transport of solutes.

List the functions of the subcutaneous layer or the hypodermis.

Pads and protects body; acts as an energy reservoir; provides thermal insulation; extensive vascular network promotes rapid absorption

Explain the four functions of epithelial tissue.

Physical protection; Selective permeability; Secretions (gland cells); sensations (touch, pressure, temperature, pain)

Describe the structure of the plasma membrane.

Plasma membrane is a fluid matrix composed of approx equal mixture of lipids and proteins. It regulates the movement of substances both into and out of the cell.

State the source of energy that drives primary active transport.

Primary active transport uses energy directly derived from the breakdown of ATP.

List and briefly explain the seven functions of the skin.

Protection; prevention of water loss and gain; metabolic regulation; secretion and absorption; immune; temperature regulation; sensory reception

Describe the structure of RNA and its function.

RNA is the ribonucleic acid, which includes the five-carbon surgar ribose, a phosphate, and one of four nitrogenous bases: adenine, cytosine, guanine, and uracil.

Differentiate between simple diffusion and facilitated diffusion.

Simple diffusion occurs when solutes that are small and nonpolar move into or out of a cell down their concentration gradient without a transport protein; they simply pass b/t the phospholipid molecules. Facilitated diffusion is when small solutes that are charged or polar must be assisted by plasma membrane proteins in order to cross the phospholipid bilayer.

Classify three different epithelial tissues based on number of cell layers.

Simple epithelium- one cell layer thick; direct contact w/basement membrane; minimal stress and filtration, absorption, secretion (air sacs of lungs, intestines, blood vessels) Stratified- two or more layers; resembles brick wall; structural support or better protection; found areas subjected to abrasive activities or mechanical stresses; basal layer continuously regenerate as apical layer is lost Pseudostratified- appears layered b/c nuclei are distributed at different levels

Describe the two layers of the dermis.

Superficial papillary- projections called dermal papillaeinterdigitate with epidermal ridges; containsensory nerve endings that serve as tactile receptors Deeper reticular layer- means "network"; large bundles of connective fibers are interwoven with follicles, sebaceous and sweat glands, nerves and blood vessels

Describe the two common types of exocrine glands.

Sweat (sudoriferous) and sebaceaous (oil)

Distinguish between symport and antiport and give one example for each.

Symport secondary active transport is when the 2 substances are moved in the same direction, such as when glucose binds to the transport protein, allowing both the glucose and the Na+ to move into the cell. Antiport is when the 2 substances move in opposite directions, such as when the H+ is moved out of the cell, by the energy provided by Na+ moving into the cell.

Explain the importance of cleavage lines and the formation of stretch marks.

Tension lines: cutting perpendicular results in slow healing and increased scarring Stretch marks are formed when skin exceeds elastic capacity and collagen fibers are torn

State the organic molecule (lipids or proteins) that forms the major component of the plasma membrane.

The membrane is mostly made up of the phospholipid bilayer, which ensures the cytosol remains inside the cell and the interstitial fluid (fluid outside the cell) stays outside.

Define resting membrane potential in relation to the distribution of sodium and potassium across the cell membrane.

The resting membrane potential is the electrical charge difference that represents potential energy, specifically when the cell is at rest. -> A cell must have an unqueal distribution of ions and molecules across the plasma membrane. The cytosol has more K+ than the surrounding interstatial fluid, which has a higher concentration of Na+ than the cytosol. In addition, the cytosol has negatively charged protein molecules, which are too large to pass through teh membrane. -K+ is chemically attracted to the outside (due to the lower concenrtraion), but electrically opposed, due to the higher positive charge outside the cytosol. When the chemical pull equals the electrical pull, the K+ reaches equilibrium. - The Na+ moving into the cell, makes the inside more positive.

Explain the function of sodium-potassium pump in relation to the movement of those ions.

The sodium-potassium (Na+/K+) pump is a special type of ion pump (exchange pump). It moves Na+ out of the cell and K+ into the cell. There is a 1:2:3 ratio -- 1 ATP is required to pump 2 K+ ios into the cell and 3 Na+ ions out of the cell.

State the source of energy that drives secondary active transport in connection to primary active transport.

The source of energy for secondary active transport is the kinetic energy of one substance moving down its concentration gradient provides the power to pump the other substance across its concentration gradient.)

Explain the two stages of the cell life cycle.

The two states of the cell life cycle are interphase and mitotic phase. Interphase is the time the cell prepares for division. It includes three phases: G1 phase (cells grow and producd new organelles and other structures needed for DNA replication.), S phase (during which the 46 double helix strands of DNA are replicated), and G2 phase (when centriole replication is completed and the enzymes and other structure needed for cell division are synthesized.

State the cell types for each type of cell division.

The two states of the cell life cycle are interphase and mitotic phase. Interphase is the time the cell prepares for division. It includes three phases: G1 phase (cells grow and producd new organelles and other structures needed for DNA replication.), S phase (during which the 46 double helix strands of DNA are replicated), and G2 phase (when centriole replication is completed and the enzymes and other structure needed for cell division are synthesized.

Define translation and explain where it occurs in the cell.

Translation is the synthesis of new protein and takes place at ribosomes within the cytosol. The mRNA is threaded through a ribosome, and the information is "read"....the code in the nucelotide of the mRNA is translated, meaning that it is converted into the language of amino acids to produce a newly formed strand of protein.

Define vesicular transport.

Vesicular transport is the transport of large substances across the plasma membrane by vesicle (a membrane-bound sac filled with materials). (Also called bulk transport). It is active transport (because it requires energy from the cell).

List the two components that make up the cytoplasm.

cytoplasm and organelles

Briefly describe the functions of hair.

protection; facial expression in eyebrows; heat retention; sensory reception via hair root plexuses that detect light touch; visual identification; chemical signal dispersal (pheromones

Identify the structure and describe the function of the various types of connective tissue listed below:

see tissue table