Anatomy OPT112 (copy)

standard anatomical position

\-body upright

\-legs slightly apart with feet facing forward and flat on the ground

\-arms at the side with palms facing forward

\-eyes and head directed straight ahead

body plane

imaginary lines through the body

body sections

slices through the body created by the plane

sagittal plane

plane that divides the body or an organ vertically into right and left sides

\-if it is directly down the middle: midsagittal

\-if it is not down the middle: parasagittal

coronal (frontal) plane

divides the body or an organ into an anterior and a posterior portion

transverse (cross-sectional) plane

divides the body or organ horizontally into upper and lower portions

\-produce images referred to as cross sections

oblique planes

dividing the body/organ at an angle

coronal suture

separates frontal and parietal bones

\-divides anterior and posterior parts of the skull

sagittal suture

\-divides parietal bones into right and left halves

\-divides skull into left and right

anterior

in front of

posterior

in back of

dorsal

towards the back side of the human body

ventral

toward the belly side of the human body

superior

closer to the head

inferior

closer to the feet

cranial (cephalic)

toward the head end

caudal

toward the rear or tail end

rostral

toward the nose or mouth

medial

toward the mid-line of the body

lateral

away from the mid-line of the body

ipsilateral

on the same side

contralateral

on the opposite side

deep

closer to the inside

superficial

closer to the outside

proximal

closer to the point of attachment to trunk

distal

farther away from point of attachment to trunk

dorsal body cavity

brain and spinal cord

ventral body cavity

1. thoracic (lungs, trachea, great vessels, heart, esophagus)
2. abdominal (major GI tract organs, spleen, kidney)


1. Pelvic (terminal GI tract organs, urinary bladder, reproductive organs)

serous membranes

\-line ventral body cavities


1. visceral layer: covers external surface of organs
2. parietal layer: covers internal wall of body cavity
3. serous cavity: potential space between the layers, filled with serous fluid

abdominal regions

1. Right upper quadrant (contains liver)
2. left upper quadrant (contains stomach)
3. right lower quadrant (intestines)
4. left lower quadrant (intestines)

fenestrations

small openings/windows (there is also fenestrated capillaries)

foramen

a short passage (doorway)

ex. foramen magnum (where brain stem passes)

canal/meatus

passage through a tube (hallway)

ex. optic canal

fossa

concavity

fissure

deep groove

process

extension

ramus

bifurcation, forked

cell

the basic, living, structural, and functional unit of the body

function of a cell

* compartmentalization of chemical reactions within specialized structures
* regulate inflow and outflow of materials
* utilize genetic material to direct cell activities

cytology

cell biology, study of cellular structure

cell physiology

study of cellular function

cell destiny

* to remain alive and functioning, the grow and divide, or to die


* homeostasis must remain a balance between cell multiplication and cell death
* the protein cyclin builds up during interphase and triggers mitosis (TO GROW AND DIVIDE)
* programmed cell death (apoptosis) occurs if a triggering agent turns on suicide enzymes that kills the cell
* Necrosis is cell death caused by injury or infection

nonmembranous organelles

Lack membranes and are in direct contact with the cytoplasm

* Ex. Ribosomes

Membranous organelles

* Surrounded by one or two lipid bilayer membranes
* Allows organelles to do specific function regardless of what is happening in the rest of cell
* Majority of organelles
* Only organelle with a “true” 2 lipid bilayer is the mitochondria
* nuclear envelope could be argued as well

scanning electron microscopy (SEM)

* provides a nice 3D view
* Shows external structures
* electrons shot at specimen and bounced back

Transmission electron microscopy (TEM)

* Shows internal structures
* Electron shot through specimen

Light microscope

* Resolution not the best
* Can really only get to 0.2 micrometers (would not be able to see ribosomes in a cell)

Structure of nucleus

* Largest organelle within a cell (5-7 micrometers)
* Round or oval body located near the cell center
* Surrounded by a nuclear envelope composed of two membranes
* envelope contains nuclear pores (transmembrane proteins)
* messenger molecules pass between the nucleus and the cytoplasm through these pores
* Require facilitated movement in/out of pores
* No membrane-bound organelles are present in the nucleus
* nucleus contains coiled strands of DNA known as chromatin (which condense to form chromosomes at the time of cell division)

Function of the nucleus

* Stores and transmits genetic information in the form of DNA
* Genetic information passes from the nucleus to the cytoplasm, where amino acids are assembled into proteins

Structure of the nucleolus

* Densely stained filamentous structure within the nucleus
* consists of proteins associated with DNA in regions where information concerning ribosomal proteins is being expressed

Function of the nucleolus

* Site of ribosomal RNA (rRNA) synthesis
* Assembles RNA and protein components of ribosomal subunits, which then move to the cytoplasm through nuclear pores

Nuclear pores

* projects into the cytosol
* very small substances can pass through pore
* large substances requires interaction with transmembrane protein for passage
* typical nucleus has 800-1000 nuclear pores

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nuclear membrane (nuclear envelope)

outer bilayer of nuclear membrane is continuous with membrane of rough ER

nuclear pores

-projects into the cytosol
-very small substances can pass through the pore
-large substances requires interactions with transmembrane protein for passage
-typical nucleus has 800-1000 nuclear pores

ribosomes

- packages of ribosomal RNA (rRNA) and protein
-has a small subunit and a large subunit: only once it is assembled is it a functional ribosome
-within mitochondria, ribosomes synthesize mitochondrial proteins

free ribosomes

-found throughout the cytosol
-function is to synthesize proteins found inside the cell from mature mRNA

membrane-bound organelles

-attached to endoplasmic reticulum (rough) or nuclear membrane
-synthesize proteins needed for plasma membrane or for export
-multiple (10-20) form a polyribsome

polar amino acids

easily interact with other polar molecules in a hydrophilic environment
-do not pass through cell membrane easily without transport

nonpolar amino acids

easily interact with other nonpolar molecules in a hydrophobic environment
-like lipids (lipophilic)
-readily pass through a cell membrane (nonpolar and uncharged molecules)

charged amino acids

-very hydrophilic
-do not pass through cell membrane easily without transport

primary protein structure

chain of amino acids

secondary protein structure

coiling or folding of a polypeptide due to H-bonding between amino acids
-alpha helix or beta sheet

tertiary protein structure

three-dimensional folding pattern of a protein due to side chain interactions

quaternary protein structure

multiple proteins connect by disulfide bridges and hydrogen bonds
-can overall change polarity of the molecule and shift confirmation

proteins that regulate gene expression

-synthesize RNA from DNA
-synthesize polypeptides from RNA

transporter proteins

mediate the movement of solutes such as ions and organic molecules across plasma membranes

enzymes

accelerate the rate of specific chemical reactions, such as those required for cellular metabolism

cell signaling proteins

enable cells to communicate with each other, themselves, and with the external environment

motor proteins

initiate movement
-actin and myosin

structural proteins

support, connect, and strengthen cells, tissues, and organs

defense proteins

Protect against infection and disease due to pathogens
-cytokines and antibodies

endoplasmic reticulum

-network of membranes forming flattened sacs or tubules called cisterns
-the ER takes up 1/2 of membranous surfaces within the cytoplasm
-continuous with outer nuclear membrane

rough endoplasmic reticulum

-continuous with nuclear envelope and covered with attached ribosomes
-synthesizes. processes, and packages proteins (into vesicles and sends to golgi complex) for export
-free ribosomes synthesize proteins for local use

smooth endoplasmic reticulum

-no attached ribosomes
-synthesizes phospholipids, steroids, fats, and carbohydrates
-detoxifies harmful substances (ex. alcohol)

golgi apparatus structure

-adjacent to the endoplasmic reticulum
-series of cup-shaped, closely apposed, flattened, membranous sacs
-associated with numerous vesicles located nearby
-generally, a single golgi apparatus is located in the central portion of a cell near its nucleus

golgi apparatus function

concentrates, modifies, and sorts proteins arriving from the rough ER prior to their distribution via the golgi vesicles to other organelles or outside the cell

golgi complex: packaging of proteins

1. proteins pass from the rough ER to golgi complex in transport vesicles (1-2) where they fuse with the entry cistern (3)
2. proteins pass from entry cistern to medial cistern from processing (glycosylation) and then to the exit cistern by transfer vesicle (4-5)
3. Finished proteins exit golgi as secretory (7), membrane (8), storage vesicle, the lysosome (9) to plasma membrane

lysosomes

-"membranous vesicles"
-formed in golgi complex and filled with digestive enzymes
-pumps in hydrogen ions by active transport from cytosol until internal pH reaches 5.0

functions of the lysosome

-digest foreign substances (i.e. bacteria)
-digest and recycle components of the cell's organelles (autophagy) or in cases of cell destruction (autolysis)

peroxisomes

-vesicles with a membrane similar to those associated with lysosomes
-replicate by mitosis (form by division of preexisting peroxisomes)
-smaller than lysosomes
-contain enzymes that oxidize organic material
-pH is not very acidic compared to lysosomes

function of peroxisomes

-part of normal metabolic breakdown of amino acids and fatty acids
-oxidizes toxic substances such as alcohol and formaldehyde
-contains catalase which decomposes H2O2 (hydrogen peroxide)

Mitochondria

-double membrane organelles
-central cavity is known as the matrix
-inner membrane folds are known as crista (function is to increase surface area in the mitochondria)

function of the mitochondria

-ATP generation
-powerhouse of the cell

replication of mitochondria

-mitochondria self replicate
-have circular DNA with 37 genes
-DNA is only inherited from mother because sperm mitochondria break off at fertilization (midpiece and tail break off and the midpiece is where the mitochondria is in a male)

cytosol

-intracellular fluid
-55% of cell volume
-the liquid part of the cytoplasm
-site of many important chemical reactions, such as production of ATP, synthesize of building blocks for organelles

parts of the cytosol

75-90% water with other components:
-large organic molecules (proteins, carbohydrates, lipids) suspended by electrical charges
-small, dissolved organic molecules (simple sugars) and ions
-large aggregates of lipids droplets and glycogen granules (inclusions) (pigment inclusions)

cytoskeleton

-network of protein filaments throughout the cytosol (microfilaments, intermediate filament, microtubules)
-continually reorganized based on needs of the cell

cytoskeleton functions

-provides cell support and shape
-organization of chemical reactions
-cell and organelle movement

microfilaments

-thinnest filaments made of actin
-for locomotion and division
-support microvilli
- 7 nanometers in diameter
-g-actin protein subunit

intermediate filaments

-several different proteins
-desmosomes anchor intermediate filaments
-anchor organelles
-10 nanometers in diameter
-several proteins are the protein subunits

microtubules

-large cylindrical structures composed of tubulin
-spiral-like structure
-flagella, cilia, and centrosomes made up of microtubules
-are the railroad tracks for motor proteins to transport vesicles
-25 nanometers in diameter
-tubulin is the protein subunit

centrosome

-found near nucleus
-has the pericentriolar area surrounding the centrosome
-composed of 2 centrioles (90 degrees to each other)
- centrioles are composed of 9 clusters of 3 microtubules (9+0 array)
-play a vital role in formation of cilia and flagella: "basal bodies": in base of cilia/flagella (has same arrangement)

pericentriolar area

formation site for mitotic spindle and microtubules
-surrounds the centrosome

transport via motor proteins

motor protein (ATP) powered "walks" vesicle along the microtubule of cytoskeleton

cilia and flagella structure

-shaft contains pairs (doublets) of microtubules (9+2 array) (has a center doublet)
-covered by cell membrane
-basal body is centriole responsible for initiating its assembly (microtubule arrangement different than in shaft)

differences in cilia and flagella

-cilia are short and multiple (respiratory)
-flagella are longer and single (reproductive)

movement of cilia

-stiff during power stroke but flexible during recovery
-many coordinated together
-locations are airways and uterine tube

movement of flagella

-single flagella wiggles in a wavelike pattern
-propels sperm forward

plasma membrane

-flexible but sturdy barrier that surround cytoplasm of cell
-fluid mosaic model

fluid mosaic model

-lipid and protein held together by hydrogen bonds
-lipid is barrier to entry or exit of polar substances (small to medium nonpolar can readily pass)
-embedded proteins serve as "gatekeepers" which regulate traffic
-small amounts of carbohydrates in plasma membrane
-ratios of lipids/proteins/carbohydrates that comprise the plasma membrane vary depending on location within human body