prelims zoology lab
DESCRIPTION
compilation of zoology lab experimentsTRANSCRIPT
EXERCISE NO. 1
The Compound Microscope
Parts FunctionsBase Bottom most part that
supports the entire microscope
Pillar Part above the base that supports other parts
Inclination Joint Allows microscope to tilt/straighten
ArmCoarse Adjustment Knob
Large knob used for focusing the specimen
Fine Adjustment Knob Small knob for fine-tuning the focus
Body Tube Attached to the arm, holds the eye piece
Draw Tube Holds ocular lensesRevolving Nose Piece Where objectives are
attached toOBJECTIVES
1. Scanning2. MPO3. HPO4. Oil Immersion
1) 4x, shortest tube
2) 10x3) 40x4) 100x, the
longest tubeEye Piece/ Ocular Part where the
observer looks at the specimen
Dust Shield Protects objectives from foreign objects
Stage PlatformStage Clips Holds slideILLUMINATING PARTS
1. Illuminator2. Condenser 3. Iris Diaphragm
1) Light-source2) Controls &
concentrate light to the specimen
3) Regulates amount of light
N.B. The newer models have no INCLINATION JOINTS
QUESTIONS:
1. What is the microscope? An optical instrument used for viewing
very small objects, such as mineral samples or animal or plant cells, typically magnified several hundred times.
2. Name (3) Biologists who employed the microscope in their work. Describe briefly their work to zoology. Malpighi Anton Van Leeuwenhoek Robert Hooke
EXERCISE NO. 3
MAGNIFICATION
QUESTIONS:
1. What is magnification?- The act making something look larger than it is.
N.B – Total Magnification=multiplication power of the ocular x Objective
OBJCTV 4x 10x 15x 40x 60x5x 20x 50x 75x 200x 300x
10x 40x 100x 150x 400x 600x15x 60x 150x 225 600x 900x
EXERCISE NO. 4
THE ANIMAL CELL
QUESTIONS:
1. What parts of the animal cell were common to the paramecium and the squamous cell as observed under HPO?
- Nucleus and cytoplasm.
PLANT ANIMALCell Wall Made of
celluloseabsent
Plastids Present AbsentVacuoles Present,
stores vitamins
Small transportation
Nucleus Located at the side
Center
Locomotion No movement
Yes
Shape Rectangular Round & Irregular
Structure Rigid Lack RigidityCell Division Daughter
cells separated in cell plate
Daughter cells separate in cleavage furrow
Chloroplasts Present AbsentLysosome Absent Present, in
cytoplasmCilia Very rare Present
Comes in various size and tend to have different shapes
Not in Plant cells Not in Animal CellsLysosome Cell WallCentrioles VacuoleCilia PlastidsFlagella
A. ANIMAL CELLS PARTS1. Cell membrane
- Fluid mosaic lipid bilayer studded with proteins.- Integral protein, CHO acts as a door.- allows communication b/w cells.
2. Cytoplasm- consists of all cellular organelles.- Responsible for cell division.a. Cytosol- fluid portion of the
cytoplasm. Transports proteins.
b. Cytoskeleton- Maintains shape.3. Nucleus
- encloses genetic material.- Brain of the cell.
-Houses chromosomes – made up of chromatins.
Nuclear Pores- allow substances to pass & communicate with the cytoplasm.
Nuclear Envelope (ENDOMEMBRANE SYSTEM) - double membrane that surrounds it.
Nuclear Lamina- a net like array of protein filaments that maintains the shape of the nucleus.
Nucleolus- makes ribosomes. 4. Mitochondria
-“Power house of the cell”-has its own DNA-Thread granuleGenerates brown fat-used in hibernation.-converts chemical energy to ATP-double membrane.-divides by binary fission.-synthesis, modification and breakdown of cellular molecules. - Cellular Respiration-exchange of gases.-synthesis of hormones.
5. Ribosomes -Contains RNA & Proteins – from amino acids.-Protein Synthesis.-Assembles proteins.-free & bound ribosomes.
6. Endoplasmic Reticulum-works on proteins.-double sac.-closer to nucleus.-makes membranes.a. Rough ER-glycosylation glycoproteins-aids in the synthesis of secretory and other proteins.b. Smooth ER
- Synthesis of lipids, metabolism of CHO.-accumulates calcium ions transports to ER lumen.c. Transitional ER-transports vesicles to rough ER.
7. Golgi Apparatus- Consists of Cisternae -Membranous
network of flattened sacs.- Continues glycosylation.- Sorts, modifies, packages &
transports macromolecules.- Camillo Golgi.- Proteolysis
3 COMPARTMENTS:1. Cis2. Medial3. Trans
8. Lysosome- Single internal membrane.- Phagocytosis-engulfing smaller
organisms.- AUTOPHAGY - Suicidal bodies
-intracellular digestion.
EXERCISE NO. 5
ANIMAL CELL DIVERITY AS TO CELL SHAPE
OOGONIA- immature cells
OOCYTES- maturing egg cells
Located at the Graafian Follicles LACUNAE – minute spaces
Spider-like/Web-likeStellate (neurons) Gray matterIrregular No definite
cell form, but do not have the ability to change shape/form.
Amorphous No specific form, but can change in form
Flagellated With thread like tails (For locomotion)
Fusiform Narrow with tapered ends
Filamentous Broader with blunt ends
Cell Shape FunctionSperm cell Flagellated LocomotionOvum Spherical ReproductionAmoeba Amorphous LocomotionIntestinal lining Columnar AbsorptionSmooth muscle Fusiform Slow
contractionSkeletal Muscle Cylindrical Rapid actionSpinal Cord Stellate Transmission
of impulsesBone Web-like SupportHuman RBC Circular &
biconcave (not nucleated
Transport of gases. (cellular respiration)
Trachea Columnar SupportLiver Polygonal Storage and
ExcretionKidney Cuboidal ExcretionFrog chrompatophores
Irregular Pigmentation
Palm Skin Flat Protection
DUODENUM
-part of small intestine
-Blank spaces- goblet cells
SKELETAL MUSCLE
-there are striations
FROG SPINAL BONE- 1 circle = Haversian System/System- Where blood vessels are contained
= Haversian canal / Central Canal.- Rings are lamellae.
ACTIVITY NO. 6
CELL DIVISION
A. Reasons for Cell Division1. Growth2. Repair and replacement of damaged
cells.3. Reproduction of species
B. Types of Cell Division1. Amitosis
- Direct nuclear Division2. Mitosis
- To produce two identical cells.
GENERAL SCHEME
- DNA duplicates to produce 2 sister chromatids.
- Chromosomes attach to the spindle and separate.
- Makes 2 identical cells that are diploid.
MITOSIS
a. Interphase The cell obtains nutrients and
metabolizes them, grows, reads its DNA, and conducts other "normal" cell functions.
b. Prophase- The chromosomes supercoil and the fibers of the spindle apparatus begin to form between centrosomes located at the pole of the cells.
EARLY PROPHASE & LATE PROPHASE
c. Metaphase
The condensed sister chromatids are moved to the middle of the nuclear region to form a metaphasic plate.
d. ANAPHASE- The single centromere that has heldThe two chromatids together now splits.
EARLY ANAPHASE (8)
- The chromosomes move toward their respective poles, pulled by the kinetochore fibers.
LATE ANAPHASE (9)
- The centrosomes move farther apart.
e. TELOPHASE- Spindle fibers disappear and chromosomes lose their identity.
EARLY TELOPHASE
AMITOSIS- meiosis SEXUAL
MITOSIS- ASEXUAL reproduction
AMITOTIC- reproduction of cells.
Ex. Egg cells, sperm cells, germ cells.
MIOTIC- slower ex. Skin
MEOTIC-happens in 48 hours, 4 daughter cells.
EXERCISE NO. 7
PHYSIOLOGICAL ACTIVITIES OF CELLS
A. PASSIVE TRANSPORT-HIGH LOW CONCENTRATION-molecules move RANDOMLY.a) DIFFUSION
-random mixing of particles that occurs in a solution.- Both the solute and the solvent undergo diffusion-HIGH LOW concentration-Equilibrium is reached when the molecules are evenly distributed throughout the solution. FACTORS AFFECTING DIFFUSION1. Steepness of concentration gradient2. Temperature3. Size or Mass of diffusing substance4. Surface area5. Diffusion distance
b) OSMOSIS-Diffusion of water through a selectively permeable membrane.- HIGH LOW concentration.
c) FACILITATED DIFFUSION-diffusion with the help of transport proteins.-specific, transports larger molecules-HIGH LOW concentration
B. ACTIVE TRANSPORT-pumping of molecules (Protein pumps) against their concentration gradient.Ex. Sodium Pumps -LOW HIGH CONCENTRATIONa) ENDOCYTOSIS
- Taking BULKY material into a cell.- Uses energy- “Cell eating”- Forms food vacuole & digests food.- Ex. WBC eating bacteria.
b) EXOCYTOSIS- FORCES material OUT of the cell.
- Ex. When cell changes shape (happens in vesicles).
C. HYPOTONIC SOLUTION- Low solute; High water
RESULT:
- Cytolysis (Cells swell and bursts open)
D. HYPERTONIC SOLUTION- Low water; High solute
RESULT:
- Plasmolysis (Cells shrinks)E. ISOTONIC SOLUTION
- SOLVENT = SOLUTE
RESULT:
- Homeostasis- Dynamic Equilibrium
EXERCISE NO. 8
EPITHELIAL TISSUES
EPITHILIUM
- Cellular layer- Cells compactly arranged bound
together by a very little quantity of matrix or intercellular fluid.
- Lies above basement membrane- AVASCULAR
CLASSIFICATION
A. SIMPLE/ NON- STRATIFIEDB. STRATIFIEDC. PSEUDOSTRATIFIED
-“Pseudo”- false.TYPES
A. CUBOIDAL – cube shapedB. COLUMNAR - rectangularC. SQUAMOUS – flatD. TRANSITIONAL- changes shape
TYPES ACCORDING TO LAYERS AND CELLS
1) SQUAMOUS Simple – blood vessels and arteries Stratified – Skin, Esophagus, Anus, and
Vagina.2) CUBOIDAL Simple – kidney and surface of the ovary Stratified – ducts of adult sweat gland3) COLUMNAR Non-Ciliated Simple – gastro intestinal
track, ducts of glands, gallbladder. Ciliated Simple- upper respiratory track,
uterine tubes, uterus, spinal cord. Stratified- part of urethra, ducts of some
glands Pseudostratified- upper respiratory track,
epididymis 4) TRANSITIONAL Urinary bladder, ureter, urethra.
Location FunctionSkin, blood vessels.
Allows materials to pass. Secretes lubrication substance.
Liver and in kidney tubules.
Secretes and absorbs.
Ciliated- uterine tubes, uterus.Non- Ciliated- small intestine, bladder.
Absorbs; also secretes mucus and enzymes.
Trachea & upper respiratory tracks
Secretes mucus, moves mucus
Esophagus, mouth, vagina
Protects against abrasions
Sweat glands, salivary glands, mammary glands
Protective tissue
Urethra, some glands
Secretes and protects
Linings of urethra, bladder, ureters
Allows urinary organs to expand and stretch
EXERCISE NO. 9
CONNECTIVE TISSUE
A. CHARACTERISTICS- From undifferentiated
mesenchymal cells- Extracellular matrix of fibers and
ground substance.- VASCULAR- Below basement membrane- Support and binding organs
together.
TWO BASIC ELEMENTS:
1) CELLS2) MATRIX
a) Ground Substanceb) Fibers
THREE TYPES OF FIBERS:
A. COLLAGEN- Occurs in bundles
- Found in bone, cartilage, tendons and ligaments.
B. RETICULAR- Finer than collagen- Support the walls of blood vessels,
nerve fibers, and skeletal and smooth muscles.
C. ELASTIC- May be arranged in fiber or
discontinuous sheets- Found in the ligaments of the skin,
blood vessel walls, lung tissues.
TYPES OF CONNECTIVE TISSUES:
1) RETICUAR2) ADIPOSE3) ELASTIC4) FIBROUS
-Dense fibrous/ fibrous CT – tendon-Loose fibrous areolar
EXERCISE 10SUPPORTIVE TISSUE
A. CHARACTERISTICS-provides supporting framework to the body.- Exhibit increased amount of matrix-cells are contained in tiny spaces or LACUNAE- includes CATRILLAGES and BONES.
B. CARTILLAGE- Dense and firm tissue- Resists TENSION and COMPRESSION- Lots of collagen and elastic fibers- No nerves or blood vessels- High content of PROTEOGLYCANS
(flexible) 80% water.- Chondroblasts makes matrix until
end of human adolescence.- LACUNAE – mature chondrocytes.
-SUPPORT AND REPAIR – hematopoiesis
C. TYPES OF CARTILLGE1) HYALINE
-above collagen-no fibers-Glassy, resists dye-few chondrocytes, all found in LACUNAE-Reduce, FRICTION; Absorbs, PRESSURE- flexible-covers END of long bonesPerichondrium – surrounds the cartilage.
2) ELASTIC -more elastic-almost identical to hyaline.-Matrix appears more fibrous –pleripherated -More lacunae, closely spaced- found in ear, auditory tube, epiglottis
- Gives support, maintains shape, allows flexibility.
HYALINE VS ELASTIC
E – Intermediate size thickness
H- less fibrous than E.
3) FIBROCARTILLAGE- Tough binding tissue- ROWS of chondoytes and collagen
fibers- Compressible and RESISTS tension.- Found in intervertebral discs.
D. BONE (OSSEOUS TISSUE)-most supportive tissue-more collagen surrounded by calcium salts- well VACULARIZED -Osteocytes stored in lacunae- bone marrow stores fat and makes blood cells.-Matrix is known as LLAMELAE HAVERSIAN SYSTEM = 1 circleHAVERSIAN CANAL =where blood vessels are locatedOSTEOCYTE-CANALICULI- webs connected to osteocyte. VOLKMANN CANAL- transmit blood vessels from the periosteum into the bone and that communicate with the Haversian canals.