POLICIES• Attendance• ID & uniform• Quizzes• Grading System – 40%
Quizzes – 30%Manual – 10%Exam – 60%
Anatomy-Physiology•Anatomy – “ana” (apart) “tomy” (to cut),
study of the structure and shape of the body and body parts and their relationships to one another.
•Physiology – “physio” (nature) “ology” (the study of)
study of how the body and its parts work or function.
THE CELL
Monina C. Montenegro, MD, DPSP
Antoni van Leeuwenhoek
• (1632-1723), Dutch, maker of first single lens microscope
• The first to document the structure of RBC & the nature of the circulatory system
• protozoans & bacteria, life cycles of many species of insects.
Micrometer = (µm) metric unit = 1/1000
Types of microscopes1. Compound or light microscopes
Principle: light source -- sunlight
Magnification = extent to which an image is enlarged
2. Electron microscopePrinciple: beam of electrons a. Transmission (magnification: 1Mx or greater)b. Scanning (3 – D image <250,000x)
Image under Compound microscope
Scanning EMTransmission EM
Ant Tissue Paper
Pollen Blood Cells
CELL
•Robert Hooke (1665) = study the cork & other plant materials many small partitions separatingcavities cells.
•Building block of all living things
•Carry out all chemical activities needed to sustain life
• carbon, oxygen, hydrogen, nitrogen• Iron, Na, K
3 Main Regions
1. Nucleus
•“headquarters” “control center”
•DNA ▫Genetic blueprint▫Building proteins▫Cell reproduction
3 Distinct Regions
•Nuclear envelope/membrane – encloses the nucleoplasm
•Nucleoli – 1 or more round bodies, where ribosomes are assembled
•Chromatin – DNA + protein (nondividing)▫Chromosome (dividing)
2. Plasma Membranesyn: plasma membrane, plasmalemma, cell
membrane- outer covering of the cell- surround each cell separate its
contents from external environment- composed of a bilipid layer
(proteins & carbohydrates float)- regulates what enters & leaves
the cell
Cell Membrane
rane
Plant cell
Membrane Junctions
1. Tight junction= formed from fusion of adjacent cell membrane= keep digestive juices & harmful substances from damaging the organs
2. Desmosomes= an area of contact between two adjacent cells= cell membrane thickened & fine fibers (tonofibrils) extend from the desmosome into the cytoplasm
e.g. skin
3. Gap junction= allow all materials to pass between cells
e.g. nervous system
3. Cytoplasm•semifluid, “factory area”
•3 Major Elements ▫Cytosol – semitransparent, largely water▫Organelles – “little organs”, specialized
compartments, specific functions▫Inclusions – nonfunctioning, stored nutrients or
cell products (pigment, mucus, fat, crystals, etc.)
1. Mitochondria•Tiny, threadlike
(mitos) or•Sausage-shaped•“powerhouse”
- ATP
2. Ribosomes•Tiny, round, dark
bodies•Proteins +
ribosomal RNA (rRNA)
•Actual site of protein production
3. Endoplasmic Reticulum (ER)• “network within the
cell”• Fluid-filled tubules or canals• Minicirculatory system• 2 Types
▫ Rough ER – w/ ribosomes, protein synthesis
▫ Smooth ER – cholesterol synthesis/breakdown, fat metabolism, drug detoxification
4. Golgi Apparatus•Stack of flattened membranous sacs
•Modify and package proteins
5. Lysosomes•“breakdown bodies”
•digestive enzymes
•demolition sites
▫WBC’s
6. Peroxisomes•Sacs containing oxidase
enzymes•Use oxygen to detoxify
harmful or poisonous substances (e.g. alcohol, formaldehyde)
•Disarm “free radicals”▫FR → H2O2→H2O▫ liver and kidney cells
7. Cytoskeleton•cell’s “bones and muscles”•cell shape•supports other organelles•intracellular transport•cellular movements
3 Types1. Microtubules -
cell shape, cell division
2. Intermediate filaments
3. Microfilaments
8. Centriole•Rod-shaped bodies•Direct the formation of mitotic spindle
1.Cilia – “eyelashes”, hair-like e.g. cells lining the respiratory system
2.Flagella – e.g. sperm
Cell Life Cycle•2 Major Periods1.Interphase – “metabolic phase”, cell
growth, longer phase, resting from division
- genetic material (DNA) - duplicated
2.Cell division – reproduces itself
DNA Replication
•DNA – building blocks “nucleotides”
▫Deoxyribose sugar▫Phosphate group ▫Nitrogen-containing
base
DNA Replication
2 Events of Cell Division
1. Mitosis – division of the nucleus
2 daughter nuclei
2. Cytokinesis – division of the cytoplasm
MitosisSTAGES:
• PROPHASE = chromatin coil and shorten chromosomes, barlike bodies
▫ Chromosome = 2 strands of chromatids, held together by a buttonlike body, centromere
MitosisSTAGES:• METAPHASE – chromosomes cluster and align at the center
MitosisSTAGES:• ANAPHASE – movement of chromosomes toward opposite ends of the cell
MitosisSTAGES:• TELOPHASE – chromosomes uncoil and become chromatin again, nuclear envelope forms around each chromatin mass
Cell Division
CELL PHYSIOLOGY
• Definition of terms:▫ Solution – homogenous mixture of 2 or more
components (e.g. air, seawater, alcohol)
▫ Solvent – (dissolving medium) substance present in the largest amount in a solution
▫ Solutes – components or substances present in smaller amounts
MOVEMENT of SUBSTANCES MOVEMENT of SUBSTANCES ACROSS CELL MEMBRANEACROSS CELL MEMBRANE
Definition of Terms:
•Intracellular fluid – (nucleoplasm and cytosol) ▫solution containing gases (O2, CO2),
nutrients and salts dissolved in H2O. •Interstitial fluid – fluid that bathes the
exterior of cells▫nutrients (amino acids, sugars, fatty acids,
vitamins), hormones, neurotransmitters, salts and waste products.
Definition of Terms:•Selective permeability – allows some
substances to pass through it while excluding others
•Passive transport – substances are transported across the membrane w/o energy input from the cell
•Active transport – use of ATP to drive the transport process
Passive Transport Processes
1. Diffusion – movement of molecules or ionsfrom a region of higher to lower concentration (concentration gradient).
Size of the molecules Temperature
Diffusion
Simple Diffusion
MOVEMENT of SUBSTANCES ACROSS CELL MEMBRANE
PHYSICAL PROCESSESPASSIVE PROCESS
2. Osmosis = movement of water from a lower to higher concentration
through a semi-permeable membrane
Osmosis
MOVEMENT of SUBSTANCES ACROSS CELL MEMBRANEPHYSICAL PROCESSES
PASSIVE PROCESS3. Facilitated diffusi0n = protein carrier
is needed as a transport vehicle (e.g. glucose)
MOVEMENT of SUBSTANCES ACROSS CELL MEMBRANE
PHYSICAL PROCESSESPASSIVE PROCESS
4. Filtration = process by w/c H2O and solutes are forced through a membrane (or capillary wall) by fluid or hydrostatic pressure (pressure gradient)
e.g. filtering capacity of the kidney
Active Transport Processes
1. ACTIVE TRANSPORT - “solute pumping”
- when a cell requires protein carriers that use ATP to move substances across the membrane
- move against concentration or electrical gradients
Active Transport
MOVEMENT of SUBSTANCES ACROSS CELL MEMBRANE
PHYSICAL PROCESSESREQUIRE CELL ENERGY2. BULK TRANSPORT
a) EXOCYTOSIS – “out of the cell”e.g. hormones, mucus,
wastes
Exocytosis
MOVEMENT of SUBSTANCES ACROSS CELL MEMBRANE
PHYSICAL PROCESSESREQUIRE CELL ENERGY
2. ENDOCYTOSIS – “into the cell”
Phagocytosis – “cell eating”, bacteria or dead body cells
MOVEMENT of SUBSTANCES ACROSS CELL MEMBRANEPHYSICAL
PROCESSESREQUIRE CELL ENERGY
3.PINOCYTOSIS - “cell drinking”
- bulk-phase endocytosis
- droplet or extracellular fluid containing dissolved proteins or fats- e.g. intestinal lining, kidney tubules
Table. 3.2
EFFECT of OSMOSIS in CELLS
ISOTONIC = same concentration as cell fluid = tissue fluids; blood plasma
0.9% NSS; 5% dextrose (glucose)
HYPOTONIC = lower concentration than cell fluid = cell swells
HYPERTONIC = higher concentration than cell fluid
= cell shrinks
Effects of osmosis
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