Transcript 3,4 cellsandbodynoaudio

Chapter 3 and Chapter 4
Cells and body organization
CELL STRUCTURE AND
FUNCTION
CELLS
TINY UNITS OF LIVING MATERIAL
 VARY IN SIZE AND SHAPE
 CHICKEN EGG- LARGE
 MOST ARE VERY SMALL

WHY ARE CELLS SO SMALL?
A CELL’S SURFACE IS THE GATE
THAT FOOD AND OXYGEN MUST
ENTER AND WASTES MUST EXIT
 AS A CELL’S SIZE INCREASES, THE
AMOUNT OF SURFACE AREA FOR
THIS EXCHANGE DECREASES
RELATIVE TO THE VOLUME
 SUFFOCATION RESULTS IF
SURFACE AREA IS TOO SMALL

LOOKING AT CELLS
MICROSCOPES ARE VERY USEFUL
 LIGHT MICROSCOPES- GOOD
 ELECTRON MICROSCOPES- MUCH
MORE POWERFUL, VERY
EXPENSIVE

CELLULAR ORGANELLES
ORGANELLES= THE CELL’S TINY
ORGANS
PLASMA MEMBRANE- SURROUNDS
THE CELL
CYTOPLASM- THE FLUID INSIDE THE
CELL MEMBRANE
NUCLEUS- THE CELL’S CONTROL
CENTER

NUCLEUS
CONTAINS DNA= THE BLUEPRINT
FOR THE CELL
 THE INFORMATION STORED IN DNA
TELLS THE CELL HOW TO MAKE
PROTEINS
 HAS ITS OWN MEMBRANE
NUCLEOLUS- CENTER OF NUCLEUS
RIBOSOMES ARE MADE HERE

IN THE CYTOPLASM...
RIBOSOMES- MAKE PROTEINS
 ER (ENDOPLASMIC RETICULUM)PACKAGES PROTEINS
-SMOOTH ER- LIPID SYNTHESIS
-ROUGH ER- RIBOSOMES ON THE
SURFACE
 GOLGI- PROCESSES PROTEINS AND
REPACKAGES THEM

SIGHTS OF THE CYTO.
LYSOZOMES- STORAGE OF
ENZYMES FOR DIGESTION
 MITOCHONDRION- BURNS GLUCOSE
AND PRODUCES ENERGY (ATP)
 CENTRIOLS- PRODUCE AND
ORGANIZE MICROTUBULES
(CYTOSKELETON)

CILIA AND FLAGELLA
EXTERNAL STRUCTURES
 USED TO MOVE THE CELL OR ITS
ENVIRONMENT
 MADE OF MICROTUBULES
CILIA- SHORT, OARLIKE- WINDPIPE
FLAGELLA- LONG, WHIPLIKE
SPERM

PLASMA MEMBRANE




A PHOSPHOLIPID BILAYER (DOUBLE
LAYER OF PHOSPHOLIPIDS)
SELECTIVELY PERMEABLE- PICKY
ABOUT WHAT GETS THROUGH
HAS EMBEDDED PROTEINS THAT SERVE
AS CHANNELS AND CARRIERS
GLYCOPROTEINS- CELLULAR
IDENTIFICATION
FUNCTION
OXYGEN AND CARBON DIOXIDE
PASS FREELY THROUGH THE
MEMBRANE
 OTHER MOLECULES MUST USE A
CHANNEL PROTEIN OR CARRIER TO
CROSS
 WATER- USES A PROTEIN CHANNEL
TO PASS THROUGH

DIFFUSION
THE RANDOM MOVEMENT OF
MOLECULES FROM AN AREA OF HIGHER
CONCENTRATION TO AN AREA OF
LOWER CONCENTRATION
 OSMOSIS- THE DIFFUSION OF WATER
ACROSS A PLASMA MEMBRANE
PASSIVE TRANSPORT- NO ENERGY IS
REQUIRED

TONICITY
AFFECTS THE MOVEMENT OF WATERBASED ON SOLUTE CONC.
 ISOTONIC- WATER AND SOLUTE CONC.
OF CELL AND FLUID ARE EQUAL
 HYPOTONIC- FLUID HAS LESS
SOLUTES/MORE WATER- CELLS SWELL
 HYPERTONIC- FLUID HAS MORE
SOLUTES/LESS WATER- CELLS SHRIVEL
TRANSPORT BY CARRIERS

FACILITATED TRANSPORTSUBSTANCE IS MOVING DOWN ITS
CONCENTRATION GRADIENT
(DIFFUSION)
- THESE LARGER MOLECULES
NEED A PROTEIN CARRIER TO
GET THROUGH THE MEMBRANE
- NO ENERGY IS USED
MORE ON TRANSPORT...
ACTIVE TRANSPORT- SUBSTANCE
IS PUMPED AGAINST THE
CONCENTRATION GRADIENT
 WORKS AGAINST DIFFUSION
- REQUIRES A PROTEIN CARRIER
- USES ENERGY

IN AND OUT
ENDOCYTOSIS- LARGE
SUBSTANCES ARE “ENGULFED” BY
THE CELL USING A PIECE OF THE
CELL MEMBRANE
 EXOCYTOSIS- A VESICLE FORMED
BY THE GOLGI FUSES WITH THE
PLASMA MEMBRANE AND DUMPS
ITS CONTENTS OUT OF THE CELL

THE NUCLEUS
NORMALLY THE DNA IS IN AN
UNCOILED STATE CALLED
CHROMATIN
 WHEN THE CELL GETS READY TO
DIVIDE, THE DNA COILS UP INTO
THICK STRUCTURES CALLED
CHROMOSOMES

NUCLEAR ENVELOPE
SEPARATES THE NUCLEUS FROM
THE REST OF THE CELL
 A DOUBLE MEMBRANE
 NUCLEAR PORES- OPENINGS IN
THE NUCLEAR ENVELOPE THAT
ALLOW PROTEINS AND RNA TO
PASS

MEMBRANES
ENDOPLASMIC RETICULUM, GOLGI
APPARATUS AND VACUOLES ARE
ORGANELLES COMPOSED MAINLY
OF MEMBRANES
 ER- A SYSTEM OF TUBULAR CANALS
ROUGH- RIBOSOMES ON SURFACE
SMOOTH- NO RIBOSOMES
 VACUOLE- A STORAGE SACK

GOLGI APPARATUS
HOLLOW PANCAKES
 PACKAGES STORES AND
DISTRIBUTES PROTEINS MADE BY
ROUGH ER
 SOMETIMES THESE SUBSTANCES
ARE MOVED OUT OF THE CELL
- EX. DIGESTIVE ENZYMES

LYSOSOME
CONTAINS DIGESTIVE ENZYMES
 DIGESTS PARTICLES TAKEN IN BY
ENDOCYTOSIS
 AUTODIGESTION- “CELLULAR
SUICIDE”- REMOVES WEBBING
FROM BETWEEN OUR FINGERS
WHILE WE ARE EMBRYOS

MITOCHONDRIA
ATP ARE PRODUCED HERE AS
GLUCOSE IS “BURNED”
 OXYGEN IS USED AND CARBON
DIOXIDE AND WATER ARE
RELEASED A WASTE PRODUCTS
 AEROBIC CELLULAR RESPIRATION

CYTOSKELETON
HELPS MAINTAIN THE CELLS SHAPE
 ANCHOR OR MOVE THE
ORGANELLES AROUND INSIDE THE
CELL
 MICROTUBULES- DIVIDE THE CELL
DURING DIVISION, FLAGELLA
(SPERM)

CELLULAR METABOLISM
ALL THE CHEMICAL REACTIONS
THAT OCCUR IN A CELL
 EVERY REACTION IN A CELL
REQUIRES A SPECIFIC ENZYME
 REACTANTS- STARTING MATERIALS
FOR A REACTION
 PRODUCTS- RESULT OF A
REACTION

ENZYMES
PROTEINS THAT SPEED UP A
REACTION
 AN ENZYME WILL ACT ON A
SPECIFIC MOLECULE CALLED A
SUBSTRATE
 HAVE AN ACTIVE SITE WHERE THE
SUBSTRATES BIND AND ARE
CHANGED

COENZYMES
NON-PROTEIN MOLECULES THAT
ASSIST THE ENZYME IN ITS “WORK”
 EX. VITAMINS- HELP YOUR
ENZYMES

AEROBIC CELLULAR RESP.
GLUCOSE + OXYGEN= WATER +
CARBON DIOXIDE + ENERGY (ATP)
 MAKES 36 ATP/GLUCOSE
 NAD+ = AN IMPORTANT HYDROGEN
CARRIER
 3 STEPS- GLYCOLYSIS, KREB’S
CYCLE, ELECTRON TRANSPORT
SYSTEM

FERMENTATION
ANAEROBIC- DOES NOT REQUIRE
OXYGEN
 PRODUCES ONLY 2 ATP/GLUCOSE
 OCCURS IN MUSCLES DURING
HEAVY USE
 PRODUCES LACTIC ACID WHICH
MAKES YOUR LEGS ACHE
HUMAN ORGANIZATION
TISSUE

SIMILAR CELLS THAT PERFORM A
SIMILAR FUNCTION
4 MAJOR TYPES OF TISSUES
1. EPITHELIAL- COVERS BODY
SURFACES AND LINES BODY
CAVITIES
2. CONNECTIVE- BINDS AND
SUPPORTS BODY PARTS
3. MUSCLE- MOVES BODY PARTS
4. NERVOUS- RECEIVES STIMULI AND
CONDUCTS IMPULSES FORM ONE
PART TO ANOTHER
EPITHELIAL TISSUE
CELLS ARE TIGHTLY PACKED
TOGETHER TO FORM A LAYER
 SKIN
 LINING OF DIGESTIVE TRACT,
CIRCULATORY SYSTEM,
RESPIRATORY TRACT

3 TYPES OF EPITHELIUM
SQUAMOUS- COMPOSED OF
FLATTENED CELLS- EX. LINES
BLOOD VESSELS
CUBOIDAL- CUBE SHAPED CELLS- EX.
KIDNEY TUBULES
COLUMNAR- RECTANGULAR PILLAR
SHAPED CELLS- EX. DIGESTIVE
TRACT LINING
LAYERS OF EPITHELIAL CELLS
SIMPLE- ONE LAYER OF CELLS
STRATIFIED- SEVERAL LAYERS OF
CELLS ARE STACKED ON TOP OF
EACH OTHER
PSEUDOSTRATIFIED- APPEARS TO BE
LAYERED BUT SOME CELLS SPAN
BOTH LAYERS
SPECIAL EPITHELIAL CELLS


CILIATED- HAVE CILIA WHICH MOVE
OTHER PARTICLES - EX. TRACHEA
GLAND CELLS- SECRETE SUBSTANCES2 TYPES
ENDOCRINE- SECRETE SUBSTANCES
INTO THE BLOODSTREAM
EXOCRINE- USE DUCTS FOR
SECRETIONS
BETWEEN CELLS...
3 TYPES OF JUNCTIONS
TIGHT JUNCTIONS- FORM A SEAL
BETWEEN 2 CELLS- DIGESTIVE
TRACT
GAP JUNCTION- OPEN CHANNEL
BETWEEN 2 CELLS- ALLOWS
COMMUNICATION- HEART
ADHESION- HOLD CELLS TOGETHERHEART
CONNECTIVE TISSUE
VERY DIVERSE
 BINDS ORGANS TOGETHER,
PROVIDES SUPPORT AND
PROTECTION. FILLS SPACES,
PRODUCES BLOOD CELLS AND
STORES FAT
 CELLS USUALLY SEPARATED BY A
MATRIX

MATRIX
SEPARATES CELLS OF CONNECTIVE
TISSUE
 CAN BE SOLID, SEMISOLID OR EVEN
FLUID (BLOOD PLASMA)

LOOSE CONNECTIVE TISSUE
MAIN FUNCTION IS SUPPORT
 MADE UP MAINLY OF CELLS CALLED
FIBROBLASTS
ADIPOSE TISSUE- STORES FAT
RETICULAR TISSUE- LYMPH NODES,
SPLEEN, BONE MARROW, THYMUSIMMUNE SYSTEM- STORE OR
PRODUCE WHITE BLOOD CELLS

FIBROUS CON. TISSUE
BINDS BODY PARTS TOGETHER
 TENDONS- CONNECT MUSCLES TO
BONES
 LIGAMENTS- CONNECT BONES
TOGETHER AT JOINTS
 CARTILAGE- A STRUCTURAL
CONNECTIVE TISSUE

CARTILAGE
FLEXIBLE
 NO DIRECT BLOOD SUPPLY SO IT
HEALS VERY SLOWLY
3 TYPES
HYALINE- MOST COMMON- NOSE AND
AT THE ENDS OF LONG BONES
ELASTIC- FLEXIBLE- EAR

CARTILAGE CONT.
FIBROCARTILAGE- CAN WITHSTAND
TENSION AND PRESSUREBETWEEN VERTEBRAE, KNEE
JOINTS
BONE
RIGID- HARD MATRIX
COMPACT BONE- SHAFTS OF LONG
BONES
SPONGY BONE- ENDS OF BONES
 LESS DENSE THAN COMPACT BONE
BUT STILL STRONG

BLOOD
HAS A LIQUID MATRIX CALLED
PLASMA (55% OF THE VOLUME)
 3 SOLID COMPONENTS
RED BLOOD CELLS- NO NUCLEUS,
CARRY OXYGEN TO OTHER CELLS
WHITE BLOOD CELLS- HAVE A
NUCLEUS, FIGHT INFECTION
PLATELETS- CELL FRAGMENTS, CLOT

MUSCLE
CONTAIN ACTIN AND MYOSIN
FILAMENTS WHICH ARE
RESPONSIBLE FOR THE
CONTRACTION
 3 TYPES

1. SKELETAL
VOLUNTARY CONTROL
 ATTACHED TO BONES
 MULTINUCLEATED
 STRIATED- ALTERNATING LIGHT
AND DARK BANDS DUE TO THE
PLACEMENT OF ACTIN AND MYOSIN
FILAMENTS

2. SMOOTH
NO STRIATIONS
 NOT VOLUNTARY
 FOUND IN DIGESTIVE,
CIRCULATORY AND OTHER
SYSTEMS
 CONTRACTS MORE SLOWLY THAN
SKELETAL MUSCLE , BUT IT CAN
REMAIN CONTRACTED FOR A
LONGER TIME

3. CARDIAC MUSCLE
FOUND ONLY IN THE WALLS OF THE
HEART
 HAS STRIATIONS LIKE SKELETAL
MUSCLE, BUT IT IS NOT UNDER
VOLUNTARY CONTROL
 COMMUNICATION TO SYNCHRONIZE
CONTRACTIONS IS DUE TO GAP
JUNCTIONS BETWEEN THE CELLS

NERVOUS TISSUE
CONDUCTS ELECTRICAL IMPULSES
 MADE OF CELLS CALLED NEURONS
THAT CARRY THE IMPULSE
3 PARTS- AXON= AWAY
DENDRITE= TOWARD
CELL BODY= CENTRAL PART
 NERVE- CLUSTER OF NEURONS
 NEUROGLIAL CELLS- SUPPORT AND
PROTECT NEURONS

SKIN- AN ORGAN
ORGAN= COMPOSED OF TWO OR
MORE TISSUES
3 LAYERS
EPIDERMIS- EPITHELIUM
DERMIS- CONNECTIVE, MUSCLE,
NERVOUS, EPITHELIUM (GLANDS)
SUBCUTANEOUS- CONNECTIVE
TISSUE- LAYER OF FAT
SKIN CANCER
MALIGNANT MELANOMA- DARKLY
PIGMENTED SPOT THAT LOOKS LIKE
A MOLE- UV LIGHT
 BASAL CELL AND SQUAMOUS CELL
CARCINOMAS- EPIDERMAL CELLS,
UV LIGHT, SURGICAL REMOVAL

MAJOR BODY CAVITIES
THORACIC- SUBDIVIDED INTO
CAVITIES THAT CONTAIN THE
HEART AND LUNGS
ABDOMINAL- SEPARATED FROM THE
THORACIC CAVITY BY THE
DIAPHRAGM. CONTAINS MOST OF
THE DIGESTIVE SYSTEM
MEMBRANES
A LAYER OF EPITHELIAL CELLS
THAT LINE BODY SURFACES
MUCOUS- LINE THE DIGESTIVE,
RESPIRATORY, URINARY AND
REPRODUCTIVE SYSTEMS
SEROUS- LINE THORACIC AND
ABDOMINAL CAVITIES + ORGANS
SYNOVIAL-JOINTS BETWEEN BONES
MENINGES-BRAIN

ORGAN SYSTEMS
WORK TOGETHER TO MAINTAIN THE
BODY’S INTERNAL ENVIRONMENT
MAINTENANCE
 CIRCULATORY
 DIGESTIVE
 URINARY
 LYMPHATIC
 RESPIRATORY

ORGAN SYSTEMS CONT.

INTEGUMENTARY- SKIN
ORGAN SYSTEMS CONT.
SUPPORT AND MOVEMENT
 SKELETAL
 MUSCULAR
ORGAN SYSTEMS CONT.
INTEGRATION AND COORDINATION
 NERVOUS
 ENDOCRINE
REPRODUCTION
 REPRODUCTIVE
HOMEOSTASIS
INTERNAL ENVIRONMENT REMAINS
CONSTANT EX. CONSTANT BODY
TEMP, BLOOD PRESSURE ETC.
 REQUIRES THAT ORGAN SYSTEMS
WORK TOGETHER TO KEEP CELLS
WARM, WELL FED, DISEASE AND
WASTE FREE AND HAPPY!

MAINTAINING BALANCE
NEGATIVE FEEDBACK- PROCESS
BY WHICH THE BODY CORRECTS
ITSELF TO NEGATE THE ORIGINAL
PROBLEM
 NERVOUS AND ENDOCRINE
SYSTEMS REACT TO PROBLEMS
AND CORRECT THEM

EX. BODY TEMPERATURE



BLOOD TEMP MEASURED BY THE
HYPOTHALAMUS (IN THE BRAIN)
TOO LOW- THEN NERVOUS IMPULSES
SHUT DOWN BLOOD FLOW TO SKIN +
BEGINS SHIVERING RESPONSE
TOO HIGH- THEN MORE BLOOD
CIRCULATES TO SKIN SURFACE + SWEAT
PRODUCTION