A & P Exam 1

Chemical Level of Structure

Molecules (proteins, fats)

Cellular Level of Structure

Molecules that combine to form cells (basic unit of life)

Tissue Level of Structure

Groups of cells that work together to form a tissue

Tissue types

Epithelial tissue

Muscular tissue

Nervous tissue

Connective tissue

Organ Level of Structure

Composed of 2 or more tissue types

Ex: Stomach - muscle layers, epithelial layers that secrete mucus

System Level of Structure

Consists of related organs that share a common function

Ex: cardiovascular, nervous, digestive

Organismic Level of Structure

Whole organism

Homeostasis

The body’s internal environment remains within certain physiological limits. An imbalance in homeostasis results in illness.

Negative Feedback System

Reverses the effects of the original stimulus.

• A receptor monitors changes → info. is sent to control center → effector (muslces, glands) receive info. and respond

Ex: When you go outside on a hot day? Body temp goes up, Sweating goes up, body temp goes down

Positive feedback system

Enhance original stimulus

Ex: Child birth - contractions cause more contractions

Right Upper Quadrant (RUQ)

R. lobe of liver, gallbladder, R. kidney, small and large intestine

Left Upper Quadrant (LUQ)

L. lobe of liver, stomach, pancreas, L. kidney, spleen, portions of large intestine

Right Lower Quadrant (RLQ)

Cecum (large intestine), appendix, portions of small intestine, R. ovary or spermatic cord, R. ureter

Left Lower Quadrant

Most of small intestine, portions of large intestine, L. ureter, L. ovary or spermatic cord

Matter

All forms of matter are made up of elements

Atoms

• Each element is made up of atoms

• Atoms consist of electrons (-), neutrons, and protons (+)

• The atoms of a molecule are held together by chemical bonds

Ionic bonds

• Atoms are electrically neutral (charges atom = ion)

  • If atom gains electron → negative charge

  • If atom loses electron → positive charge

• Valence shell - most atoms are stable with 8 electrons in outer valence shell

• Ionic bonds involve transfer of electrons and the attraction of opposite charged ions draws them together

• Hydrophilic - water loving

Covalent bonds

Involve sharing of electrons between 2 atoms

Nonpolar covalent bonds

Share electrons equally and remain electrically neutral

• Hydrophobic - water hating

• Ex: tossing a ball back and forth equally

Polar covalent bonds

Share electrons unequally, one atom hogs electrons

• Hydrophilic - water loving

Organic compounds

Contain carbon (C) and hydrogen (H)

• carbon can form long chains, rings, and is useful for storing energy

Carbohydrates

Contain C, H, and O

• Includes starches, cellulose (plants), and glycogen, used for energy storage

• Hydrophilic - water loving (dissolve in water)

• Have polar covalent bonds

Monosaccharides

Single-unit sugars

• Glucose (1 ring)

Disaccharides

Contain 2 units of sugar

• Sucrose (2 rings)

Polysaccharides

Contain many units of sugar

• Glycogen (stored in skeletal muscle and liver)

Lipids (fats)

Contain mostly C and H

• Used for energy storage

Triglycerides

Contain glycerol (sugar) and 3 fatty acid chains

• Nonpolar covalent bonds (hydrophobic)

Phospholipids

Contain glycerol (sugar), phosphate group, and 2 fatty acid chains

• Polar/hydrophilic head - glycerol and phosphate group (-)

• Nonpolar/hydrophobic tails - fatty acid chains

• Amphipathic - contains hydrophobic and hydrophilic regions

Steroids

Ring structures, nonpolar

• Ex: cholesterol, estrogen, testosterone

Proteins

• Play a structural role in cells

• Made up of amino acids (20 different amino acids)

• Has levels of organization: primary, secondary, tertiary, and quaternary

Primary protein structure

Sequence of amino acids

Secondary protein structure

Minor folding and bending (makes smaller)

Tertiary protein structure

3D structure (makes a knot)

Quaternary protein structure

More than 1 peptide chain

• Ex: Hemoglobin - 4 peptide chains

Enzymes

• Made of protein

• Speed up chemical reactions

• Act as catalysts (reduce energy of activation)

• Specificity - fits with substrate like a key in a lock (specific 3D structure)

• Denatured (structure destroyed) by changes in pH or temp

• Enzyme remains unaltered during reaction

• Process: E + S → ES → E + P

Nucleic Acids

RNA and DNA (deoxyribonucleic acid)

DNA

Genetic code, resembles a twisted ladder

• Consists of: nitrogen base, sugar, and phosphate

ATP

Adenosine tri-phosphate

• energy currency

• ADP + P → ATP (requires energy)

• ATP → ADP + P (releases energy

Animal Cell

Consists of:

• Plasma membrane - outer membrane

• Cytosol - fluid portion of cytoplasm (inside cell)

• Organelles - structures with specific functions

Plasma Membrane

Selectively permeable - allows certain substances in and keeps others out

Contains:

• Membrane lipids (phospholipid bilayer)

• Membrane proteins

• Small amounts of steroids and carbohydrates incorporated

Membrane lipids

Described by the fluid mosaic model

• Phospholipid bilayer: hydrophilic/polar heads face outward and hydrophobic/nonpolar tails face in

Integral proteins

Extend across the membrane, can act as a receptor, channel, or transporter

• Are amphipathic

Peripheral proteins

Attach to inside or outside of bilayer

• Are hydrophilic (polar)

Electrochemical gradient

The cell maintains a high concentration of potassium (K+) inside the cell and a high concentration of sodium (Na+) outside the cell

• Due to the Sodium/Potassium Pump

Selectively permeable

(plasma membrane)

• permeable - allows passage

• Membrane is permeable to substances that are:

  • Small

  • Hydrophobic

  • Uncharged

Passive processes

Require no ATP and move from high to low concentration

Simple diffusion

Movement of substances based on their own kinetic energy (high → low concentration)

• Until equilibrium - no net movement

Osmosis

Movement of water from hi. → lo. water concentration

• OR: movement of water from lo. → hi. solute concentration

Tonicity

Cell shape change in response to solution

• RBC (0.9% NaCl, impermeable to Na and Cl)

Hypotonic Solution

Lower water concentration inside cell

• H2O goes into cell, cell enlarges and ruptures

Hypertonic Solution

Lower water concentration outside the cell

• H20 moves out of cell, cell shrivels

Isotonic Solution

Equal water concentration in and outside the cell

• No net movement of H2O

• Happy Cell

• Ex: Saline

Facilitated Diffusion

Substances too large or too polar require a protein transporter/carrier to move down its concentration gradient

Active Processes

require ATP (energy)

Primary Active Transport

Requires a protein transporter and ATP. Moves substances against the concentration gradient

• Ex: Sodium-Potassium ATPase Pump

Secondary Active Transport

Uses ATP Indirectly

Two substances move - one substance moves down its concentration gradient and the other against its gradient

• Ex: Usually sodium moves down its concentration gradient (powered by Na/K pump) to move another substance (like H+) against its gradient

Bulk Transport

Movement of large particles. requires energy

Exocytosis

excretion of substances

Endocytosis

bringing substances into the cell

• Ex: receptor mediated endocytosis and phagocytosis

Cystic Fibrosis

• Recessive genetic disorder (both parents carry genetic mutation)

• Production of thick (immovable) mucus in respiratory, digestive, and reproductive systems. Enables bacteria to accumulate (infection)

• Physiology: Defective (CFTR) protein channel does not allow Cl- to move from inside the cell into the lumen of the various systems, H2O does not follow because osmosis disrupted

  • Lack of H2O makes mucus thick

Tissue

A group of cells with common embryonic orgin and function

• Epithelial

• Connective

• Muscle

• Nervous

Germ Layers

After 8 days of development of embryo, 3 germ layers form:

• Ectoderm (outer) , Mesoderm (middle) , and Endoderm (inner)

  • Connective t. and Muscle t. arrise from Mesoderm

  • Nervous t. arises from ectoderm

  • Epithelial t. arised from all 3 layers

Tight Junctions

Found in epithelial tissue

• Plasma membrane from neighboring cells adhere to each other

• Purpose - prevent fluid from leaking out

Gap (communicating) Junctions

Found in cardiac muscle and nervous t.

• Allows info to spread quickly

Epithelial Tissue (General Features)

• Function - lines and covers organs. Protection filtration, absorption, and secretion

• Tight junctions - cells touch

• Avascular - lack a blood supply

• Nerve supply

• High capacity for renewal - generate new cells

• Single or multiple (stratified_ layers

• Contain a free surface and a basal surface attached to connective tissue

• Nutrients from connective tissue

• Epithelial cells secrete a basement membrane which acts as adhesive to the connective tissue

Simple Squamousal Cells

Tile-like cells, one layer

• Lines blood vessels

Simple Cuboidal Cells

Square shaped

• In Kidney tubules

Ciliated Columnar Cells

Contains hairs that trap particles

• In Respiratory system - trachea and broncho

Simple Columnar Cells (Non-ciliated)

Contain microvilli which increase surface area for absorption of nutrients

• In digestive system (stomach and small intestine)

Stratified Squamousal Cells

• Contains at least 2 layers

• Cells at the basal surface continue to dived and push older cells upward

• Older cells get dehydrated, flatter, and harder on the free surface

• Cells slough off at the surface and are replaced

• Provides protection (keratin in dead cells)

Glandular Epithelia

Form endocrine or exocrine glands

Endocrine Glands

Secrete hormones into bloodstream

Exocrine Glands

Secrete products into ducts

• 3 types: Merocrine, Apocrine, and Holocrine

Merocrine Glands

Secrete product from secretory vesicles using exocytosis

Apocrine Glands

Secrete the product from the apical portion of the cytoplasm

Holocrine Glands

Secrete product by the cell bursting (and destroyed in process)

Connective Tissue General Features

• Function - binds, supports, protects the body, and stores energy

• Consists of cells, ground substance, and fibers. Matrix = ground substance and fibers

  • Ground substance - bathes cells

  • Fibers - provide strength

• Cells do not touch, separated by matrix

• Except cartilage, all vascular

• Except cartilage, has nerve supply

• Derived from mesoderm

Connective tissue cells ending in -Blast?

Immature cells, which can divide

Connective tissue cells ending in -cyte

Mature cell which cannot divide

Ground Substance

Calcified, jelly or liquid. Medium for cells, bathed in it

• Ex: Chondroitin Sulfate - jelly substance found in cartilage

Collagen Fibers

Bend but don’t stretch (3 fibers)

Elastic Fibers

Branch and do stretch

Reticular Fibers

Network, found in adipose tissue, framework for cells

Loose Connective Tissue

Many cells, fewer fibers

• Ex: Adipose and Areolar tissue

Dense Regular Connective Tissue

Less cells, more fibers, fibers are parallel

• Ex: Tendons and Ligaments

  • Tendons - connect muscle and bone

  • Ligaments - connect bone and bone

Dense Irregular Connective Tissue

Fibers are interwoven

Provides more strength in different directions

Cartilage

Consists of collagen and elastic fibers embedded in chondroitin sulfate

• Chondrocytes - mature cartilage cells that lie in spaces called lacunae

Avascular because chondrocytes produce a chemical, anti-angiogenesis factor which prevents blood vessel formation

• Slow in healing

Bone

Has calcified ground substance

• 2 types: compact or spongy bone

Compact Bone

Has circular units called osteons (in slides)

Spongy Bone

Has spaced for red marrow which produces blood cells

Blood

Liquid Matrix

• Cells: Red blood cells (no nuclei), White blood cells (nuclei), Platelets (cell fragments)

Mucus Membranes

(epithelial and connective tissue)

• Lines body systems that open directly to exterior

• Mucus keeps membranes from drying out. Protects against microbes

  • Ex: Respiratory, Digestive

Serous Membranes

(epithelial and connective tissue)

• Lines sealed cavities that do not open to exterior

• Serous fluid allows organs to glide

  • Ex: Thorax (pleura) and abdomen (peritoneum)

Synovial Membranes

(only connective tissue)

• Lines cavities of freely moveable joints

• Synovial fluid - lubricates

Muscle Tissue General Features

• Function - movement and generation or heat

• Derived from mesoderm

Skeletal Muslce

Attached to skeleton, striated and voluntary. Parallel fibers

Cardiac Muscle

Heart muscle, striated and involuntary. Branched fibers

Smooth Muscle

Found in visceral organs, non-striated and involuntary. Spindle-shaped fibers

Nervous Tissue General Features

• Function - communication between organs, tissues, ect.

• Derived from ectoderm

Neurons

Nerve cells

• Consist of dendrites, cell body, and axons