Cell Structure Review:
Cell Theory: The cell is the basic unit of structure & function in all organisms.
All cells come from pre-existing cells - Biogenesis.
Organelles:
Mitochondria - powerhouses, elongated, cristae, muscle, sperm
Golgi - secrete glycoproteins, cisternae
SER - no ribosomes, RER - have ribosomes
Cilia - short-hair-like projections, trachea
Flagella - long hair-like projections, sperm
Ribosomes - spherical, free or on ER, protein synthesis
Nucleoli - produce mRNA
Nucleus - surrounded by nuclear membrane (with pores), genetic material, controls metabolism.
Centrosome - has 2 centrioles, movement of chromosomes during mitosis.
Microvilli - cell membrane extensions, absorption of extracellular materials.
Plant Cell: chloroplasts, cell wall, large vacuole
Animal Cell: centrosome, lysosomes, small or no vacuole
Fluid-Mosaic Model of Cell Membrane Structure:
Potato-shaped proteins intermittently found in a mass of double-tailed phospholipids.
DNA, RNA, Protein Synthesis, Genetic Engineering:
DNA: Watson & Crick - double helix, building blocks = nucleotides, deoxyribose - sugar, A - T,
G - C.
RNA: single strand, ribose - sugar, no T, has U (Uracil) instead.
Protein Synthesis:
> Transcription - the genetic code for a particular protein is "transcribed" from a portion of
the DNA molecule in the nucleus to messenger RNA (mRNA), which leaves through a nuclear pore & attaches to the ribosomal
RNA (rRNA) on the surface of a ribosome, where it acts as a template for the attachment of amino acids carried over by transfer
RNA (tRNA) in a process called Translation.
> Review codon (triplet code), anti-codon, & stop codon.
Genetic Engineering - changes DNA through direct manipulation.
Restriction Enzymes - cut DNA at particular points.
Recombinant DNA - DNA formed from the combination of portions of 2 or more different DNA molecules.
Look at your Genetic Engineering Outline, notes, & labs & review:
transgenic organism (ex. Ecoli with human insulin gene), Gel Electrophoresis, DNA Sequencing, DNA Fingerprinting,
Human Genome Project (completed 2001, 3 billion base pairs, 30,000 genes), Gene Therapy, Cloning (reproductive, therapeutic),
& Genetically Engineered Foods.
Cell Division: Mitosis - exact doubling & splitting of the nucleus, yielding 2 identical
nuclei in 1 cell. Cytokinesis - splitting of the cytoplasm, yielding 2 daughter cells. Allows for growth
& repair.
Basic Stages of Mitosis:
Interphase - "resting stage", chromatin is visible, DNA replicates forming 2 chromatids attached
by a centromere.
Prophase - In an animal cell, the centrosome splits into 2 centrioles, one of which goes to one pole
& one to the other pole of the cell with spindle fibers in between, chromosomes become shorter, thicker, & visible
& attach to the spindle fibers.
Metaphase - Nucleoli & nuclear membrane dissolve, chromosome pairs line up at the equatorial
plate.
Anaphase - Chromosome pairs split, with one member of each pair going to 1 pole & the other member
to the opposite pole, guided by the spindle fibers.
Telophase - Chromosomes become diffuse & form chromatin again, spindle dissolves, nuclear membrane
forms around each set of chromosomes, & the cell now has 2 identical nuclei. THE END OF MITOSIS.
Cytokinesis:
Cytoplasm splits after mitosis, resulting in 2 daughter cells, each with an identical nucleus.
Development: zygote (fertilized egg) goes through cell division many times forming a ball of
identical cells (blastula). These cells continue to divide & then differentiate (certain segments of the DNA functions
in each cell, causing it to become muscle, nerve, bone, etc) forming an embryo. The embryo developes into a fetus &
then is born.
Some topics to think about before your midterm exam:
anatomy - structure physiology - function thorax-chest
ocular objectives diaphragm - adjusts
light medial - midline
proximal - near pt. of origin pathology - disease
kinetic energy - motion water - most common molecule
carbon, hydrogen, oxygen, nitrogen atoms electrons
protons
neutrons Big Bang Theory String Theory
Bonding-ionic, covalent
radioactive - spontaneously breakdown pH buffer
semipermeable
cell membrane-Fluid Mosaic Model cell wall - cellulose
Cell Theory - Schleidon & Schwann ribosomes --> proteins
amino acids mitochondria - powerhouses, energy prokaryotic cells
eukaryotic cells Golgi - packaging glycoproteins RER SER
anabolism - build up, synthesis catabolism - break down
irritability - respond to stimuli isotonic solution - same
hypertonic - higher mitotic spindle - made of microtubules diffusion
osmosis active transport mitosis cytokinesis genetic
engineering
epithelium - closely packed cells Cartilage - hyaline, elastic, fibro
Bone - compact, spongy Bones of body Sutures of skull
Muscles - origin, insertion, action A band I band sarcomere
Sliding Filament Theory Gene Therapy DNA RNA
transgenic organism restriction enzymes
Neurons, Action Potential, Reflex Arc:
Neuroglia - support, protect. Ex. Astrocytes
Neuron - general structure: dendrites (carry impulse toward the cell body), axon hillock, axon (carries
impulse away from the cell body), axon terminal.
Neurons classified by: structure (unipolar, bipolar, multi) or function (sensory, Inter {associative}, motor).
Action Potential (nerve impulse, AP) - Resting membrane potential (cell Polarized) ---> Stimulus ---->
changes permeability of cell membrane -----------> Na ions enter ----> Depolarization (beginning of AP) ----> AP
is self-propagating ----> directly behind AP is Repolarization.
Synapse - where the axon terminal of one neuron is close to the dendrite of the adjacent neuron. Pre-synaptic
membrane ------> Synaptic Cleft ---------> Post-synaptic membrane. Synaptic vesicles (with neurotransmitter
{ACh}).
Reflex Arc - receptor neuron (special sensory) ---> sensory neurons -------> Interneurons ----->
Motor neurons -----> to a muscle or gland (Effector).
Saltatory Response - only in myelinated neurons, impulse jumps from one node of Ranvier to the next.
Speeds up AP.
Central Nervous System
Meninges - coverings of brain & spinal cord
Dura mater - directly under skull
Arachnoid - web
Pia mater - on surface of brain & cord
Cerebrum - Lobes (frontal, parietal, temporal, occiptal)
Cerebral cortex - outer, gray matter, convolutions (gyri)
Corpus callosum - link between right & left hemispheres
Fissures - Longitudinal, Rolando, & Sylvius
Cerebellum - Arbor Vitae (Tree of Life), equilibrium, reflexes, muscle coordination.
Brain Stem ("Primitive", "Reptilian")
Medulla - respiration, BP, heart rate
Pons - skilled acts
Midbrain
Spinal Cord - sensory & motor
Spinal Nerves - 31 pair (mixed nerves)
Cranial Nerves - 12 pair (#, name, function)
Autonomic Nervous System - Parasympathetic, Sympathetic
Internal Pig: Some items you want to think about:
Incisions - ventral surface, using scalpel - through skin, then back over again through muscle: down throat
region, chest, abdomen, around umbilical cord, and down behind hind legs.
Trachea - windpipe, has cartilage rings, epiglottis over glottis.
Diaphragm - large sheet of muscle separating the thoracic & the abdominal cavities.
Heart - mammalian (4 chambered), upper chambers (atria) covered by flaps (auricles) & lower chambers
(ventricles).
Uvula - extends from soft palate in humans, but not in pigs.
Esophagus - tube, posterior to the trachea, carries food to the stomach (had bile salts, but no food).
Small Intestine - had villi (microscopic finger-like projections that increase the surface area & thus
the absorption ability of the SI). Mesentery between loops of SI.
Liver - large, brown, with gall bladder behind it.
Kidneys - have ureters to carry urine to bladder.
Eye & Vision - Think about:
3 coats of eyeball: 1) Sclera - outer, tough, white,
2) Choroid - pigmented, vascular, 3) Retina - inner, photoreceptors
Photoreceptors: Rods: most numerous, pick up dim light, Pigment is rhodopsin (breaksdown into scotopsin
& retinine {derivative of vitamin A}) Cones: mostly in fovea centralis, Pigment is iodopsin, which breaks down in
bright light.
Extrinsic Muscles: move eyes up, down, left, right. Ex. Superior rectus.
Iris: pigmented, controls size of pupil (dilates for dim light & distant object, constricts for bright
light & near object).
Lens: focuses light on retina. Helmholtz's Theory of Accomodation of the lens - For near object: ciliary
muscle contracts & lens bulges, & for distant object: ciliary muscle relaxes & lens flattens.
Blind Spot: optic disk, no rods or cones, where optic nerve leaves the retina.
Cornea: thick, tough, transparent, in front of eyeball.
Conjunctiva: thin, mucous membrane over cornea.
Light rays are refracted by cornea, lens (to greatest extent), and humors (aqueous, vitreous). Parallel
light rays converge when they pass through a convex lens, & diverge when they pass through a concave lens.
Anterior & Posterior Chambers, Optic chiasma, Occipital Lobe - Where ? What ?
Nearsightedness: myopia
Farsightedness: hyperopia
Nutrition - Some things to think about:
Nutrients:
Inorganic - water: universal solvent, chem. reactions, protoplasm, sweat. Fe (iron) - hemoglobin.
Organic - Carbohydrates: monosaccharides ----> disaccharides, yield 4.1 kcal/gram. Lipids
(fats) -->9.3 kcal/gram, Protein (100 or more amino acids linked) -> 4.1 kcal/gram. Vitamins
- not usually made by the body, needed in small amounts. C, K, A.
Food Guide Pyramid: Food groups - servings/day.
Balanced Diet:
Enzymes- Biological catalysts. React with particular substrates. See earlier chapter on chemistry.
Basal Metabolic Rate (BMR): when you are at rest, the # of calories needed to stay alive (breathing, HR,
kidneys). Ave. = 1400 - 1700 Calories/day.
Total Metabolic Rate (TMR): # of kcal/day used when you are active.
