Zoology Laboratory LBBBIO8 Term 1 2024-2025 PDF

ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 THE MICROSCOPE & ANIMAL CELL STRUCTURE MICROSCOPY CONDENSER Technique for producing visible images of Classification structures or details too small to b...

ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 THE MICROSCOPE & ANIMAL CELL STRUCTURE MICROSCOPY CONDENSER Technique for producing visible images of Classification structures or details too small to be seen by ○ For illumination. the human eye. Function ○ Using microscope or other ○ Lens under the stage and specimen. magnification tool ○ Concentrates light under the specimen. MICROSCOPE Instrument used to magnify objects that IRIS DIAPHRAGM cannot be seen by the naked eye. Classification Can either be simple or a compound ○ For illumination. microscope. Function ○ Controls the amount of light. LIGHT MICROSCOPE Generally used to observe microorganisms LIGHT SOURCE and sections of plants and animals. Classification ○ For illumination. PARTS OF THE MICROSCOPE Function ○ Reflects light through the specimen. OCULAR/EYEPIECE Classification BASE ○ For magnification. Classification Function ○ For support. ○ Contains a lens normally with a 10x Function magnification with a pointer to aid ○ Supports the body of the in locating objects within the field of microscope. view. COARSE ADJUSTMENT KNOB ARM/HANDLE Classification Classification ○ For support. ○ For support. Function Function ○ Appropriate for focusing the scanner ○ Attachment for other mechanical or LPO. parts. FINE ADJUSTMENT KNOB REVOLVING NOSEPIECE Classification Classification ○ For support. ○ For support. Function ○ Mechanical part of a microscope. ○ For final focusing. Function ○ Holds and shifts objectives. HOW TO CARRY A MICROSCOPE PROPERLY OBJECTIVES Classification Hold the handle and support the base of the ○ For magnification. microscope. Don't hold it using only the handle. Function ○ Contain lenses for magnification. HOW TO USE A MICROSCOPE Types ○ Scanner 1. Place the microscope on a flat surface and ○ Low Power Objective (LPO) connect its power cord into an outlet. ○ High Power Objective (HPO) 2. Flip on the light switch, typically located on ○ Oil Immersion Objective (OIO) the bottom of the microscope. 3. After flipping the switch, light should come STAGE out of the illuminator, which is the light source. Classification 4. Rotate the revolving nosepiece to the lowest ○ For support. power objective lens. Function 5. Once you hear the lens click into place, stop ○ Platform on which slide is rotating the nosepiece. positioned. 6. Be gentle as you rotate the nosepiece to avoid breaking it or wearing it down. STAGE CLIPS/CONTROL 7. Using the coarse adjustment knob, move Classification the stage to the lowest level possible to ○ For support. ensure that you can place the specimen in Function the stage without damaging it. ○ Holds the slide in place. 8. Remove the blue cover in the condenser. ○ Moves the slide on the stage. 9. Check and open the iris diaphragm to allow light to pass through the condenser. Dr. Jennifer Maries Yap ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 10. Get the slide with the prepared specimens. WORKING DISTANCE 11. If you notice it to be dirty, use the lens Distance between the front of the cleaner paper to clean it. microscope objective lens and the surface of 12. Place the slide in the stage. the specimen. 13. Secure it using the stage clip. 14. Use the stage control to check if you can HOW TO USE OIO move the slide in the stage. 1. Place one small drop of immersion oil on 15. Adjust the binoculars (two oculars) to the spot of light. produce a clear field of view. To ensure that 2. Slowly rotate the 100x objective into you can only see only one image. alignment while checking to make sure it 16. Now, you are ready to examine your does not strike the slide. specimen under the microscope. 3. If you were properly focused under the 40x 17. Move the microscope slide around until the objective, the 100x will rotate into place sample is in the center of the field of view. without striking the slide. 18. Adjust the iris diaphragm to control the amount of light going through the FIELD OF VIEW OF NAKED EYE VS MICROSCOPE specimen. Appears upside-down and downward. 19. If the specimen appears dark with a fully Movement appears to be in opposite open iris diaphragm, check the light source. direction than actual movement 20. Use the coarse adjustment knob (moving it closer to the objective) to slightly focus the HOW TO PREPARE WET MOUNT specimen. Use the fine adjustment to produce a clear image. 1. Add a drop of water to a slide. 21. Make sure that there is space between the 2. Place the specimen in the water. objective and the specimen placed in the 3. Place the edge of a coverslip on the slide so stage. that it touches the edge of the water. 4. Slowly lower the coverslip to prevent forming and trapping air bubbles MICROSCOPE CONCEPTS Resolving power HOW TO INSTALL THE EYE PIECE MICROMETER Magnification Field of view 1. Twist and remove the bracket. 2. Insert the micrometer inside. 3. Place the bracket back to the eyepiece. RESOLVING POWER Denotes the smallest detail that a HOW TO PUT AWAY THE MICROSCOPE microscope can resolve when imaging a specimen. 1. Clean your microscope with solution, lens Function of the design of the instrument paper, and lint-free cloth. and the properties of the light used in the 2. Clean, remove, and store your microscope’s image formation. slides. 3. Put the objective lens and nose piece on the lowest power objective. 4. Turn o the microscope’s light. 5. Unplug the cord, wrap it up, and secure it with a tie. 6. Cover the body of the microscope with a microscope dust cover. DISSECTING MICROSCOPE Useful for viewing entire specimens of small animals or body parts of larger animals. Has the added advantage of giving a three-dimensional view of the object. Able to see the full view of the specimen or MAGNIFICATION POWER insect. Ocular Lens Power x Objective Lens Power = Total Magnification Power Ocular Lens Power = 10x Objective Lens Power ○ Scanner = 4x ○ LPO = 10x ○ HPO = 40x ○ OIO = 100x FIELD OF VIEW PARFOCAL Ability of microscope to stay relatively in focus as the user switches among objectives. Dr. Jennifer Maries Yap ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 DIFFERENCE BETWEEN DISSECTING AND COMPOUND MICROSCOPE DISSECTING COMPOUND MICROSCOPE MICROSCOPE Single objective lens Multiple objective lens Has a diopter No diopter CELL THEORY AND INTERNAL ORGANELLES Viruses are not included in these categories as viruses are not independently living organisms CELL THEORY but are dependent on living cells as hosts in ROBERT HOOKE order to replicate. Living organisms were found to be composed of small compartments or pores. First scientist to name these "cells" in 1665, EUKARYOTIC CELLS PROKARYOTIC CELLS after the small rooms that monks inhabit. Contains more Contains plasmids. MATTHIAS JAKOB SCHLEIDEN specialized Botanist who found cells in all plants he organelles: examined. Endoplasmic One of the two scientists who are credited Reticulum, Golgi with developing the first two of the three Apparatus, cell theory tenets. Mitochondria, Lysosomes. THEODOR SCHWANN In 1839, he was a physiologist who also Larger ribosomes. Have 70S ribosomes. found cells in animal tissues. Consist of a 60S large One of the two scientists who are credited subunit and 40S with developing the first two of the three small subunit which cell theory tenets. comes together to form an 80S complete RUDOLF VIRCHOW ribosome In 1855, he stopped the debate of where the cell came from. PLASMIDS He is a pathologist who added the third Small circular DNA fragments known that tenet to cell theory. have the ability to replicate independently of nuclear DNA. CELL THEORY TENETS 1. All living organisms are composed of cells. 2. Cells are the structural and organizational It was thought to be a feature of prokaryotic or unit of life. bacterial cells throughout the majority of the 3. All cells come from pre-existing cells. century but according to later scientific findings, they are also present in some eukaryotic cells. Plasmids have been discovered naturally in CELL fungi and certain higher plants, but it is still Basic biological unit of all known living unclear if they exist in animal cells. organisms. All cells consist of a cytoplasm contained within a cell membrane, sometimes called PARTS OF EUKARYOTIC CELL the plasma membrane. CELL MEMBRANE Cells within an organism can di er greatly Surrounds the cytoplasm of the cell which facilitating all the di erent physiological serves to separate and protect the cell from functions required for life. its environment. Are divided into two broad categories. Composed of a double layer of All living cells share five components: a phospholipids making it very flexible. plasma membrane, cytoplasm, DNA, Able to host various proteins and semi or ribosomes and a cytoskeleton. selectively permeable. Also known as Plasma Membrane. PROKARYOTIC CELLS Include the single-cell organism bacteria CYTOPLASM and archaea. Contains all of the material in the cell excluding the cell nucleus. EUKARYOTIC CELLS Composed of the cytosol, a gel-like Animal cells, plant cells, protists, and fungi substance which is enclosed by the cell are eukaryotes membrane, and all the other organelles. Dr. Jennifer Maries Yap ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 Peroxisomes can be thought of as NUCLEUS hazardous waste recycling centers as a Cells typically contain one nucleus each, major function is to reduce the damaging although certain specialized cells may reactive oxygen species into harmless contain many. waste products. ○ Muscle cells, with others, such as red blood cells, containing none. Contains most of a cell’s DNA molecules organized as multiple linear DNA molecules known as chromosomes. Kept separate from the cytoplasm by the nuclear envelope, another double layer of phospholipids, although this membrane is punctuated by nuclear pores. MITOCHONDRIA Powerhouses of the mammalian cell generating a supply of adenosine triphosphate (ATP), for use as a source of Animal cells di er massively in size, appearance chemical energy. and function but some factors are conserved. The number of mitochondria present in a Most cells also contain a nucleus which contains cell gives an idea as to how much energy it a complete copy of an individual's DNA as well requires. as other structures such as the ○ Red blood cells have none whereas energy-producing mitochondria and cells in the liver can contain protein-producing rough endoplasmic thousands. reticulum. ENDOPLASMIC RETICULUM Has a dynamic structure and is the largest CELL MEMBRANE organelle in the cell. Defines the borders of the cell and maintain Involved in the production of proteins, the cell function. storage of calcium, and the metabolism of The plasma membrane is selectively lipids in the cell. permeable. A rough and smooth endoplasmic reticulum ○ Allows some materials to freely can be di erentiated. enter or leave the cell, while other Rough Endoplasmic Reticulum (REM) materials cannot move freely, but ○ Is studded with protein-producing require the use of a specialized ribosomes and is the major source structure, and occasionally, even of protein translation in the cell. energy investment to pass. Smooth Endoplasmic Reticulum (SEM) Has the ability to transmit signals by ○ Has a role in the formation and means of complex, integral proteins known storage of lipids, such as cholesterol as receptors. and phospholipids, which are ○ Acts both as receivers of essential for the development of extracellular inputs and as fresh cellular membranes. activators of intracellular processes. RIBOSOME ○ Provide extracellular attachment Complex cellular mechanisms which sites for e ectors like hormones translate pieces of genetic code into and growth factors, and they proteins. activate signal transduction These proteins have multiple functions like response cascades when their catalyzing reactions, providing support, or e ectors are bound. even contracting muscles. Plasma membranes range from 5 to 10 nm nanometers in thickness. GOLGI APPARATUS The membrane surfaces that face the interior and exterior of the cell are Or the Golgi body is an organelle found in hydrophilic. most cells and is a continuation of the The interior of the cell membrane is endomembrane system and functions to hydrophobic and will not interact with package proteins for dispersal throughout water. the cell, or even to the outside of the cell via secretory vesicles. PHOSPHOLIPIDS LYSOSOME AND PEROXISOME Form an excellent two-layer cell membrane that separates fluid within the Recycling centers of the cell. cell from the fluid outside of the cell. Rich in enzymes they are responsible for breaking down many kinds of biomolecules into their constituent parts for later reuse. Dr. Jennifer Maries Yap ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 ANIMAL STRUCTURE HIERARCHY OF LIFE 1. Atoms 7. Organism 2. Molecules 8. Population 3. Cells 9. Community 4. Tissues 10. Ecosystem 5. Organs 11. Biosphere 6. Organ System DIFFERENCE BETWEEN EUKARYOTIC AND The fluid mosaic model of the plasma membrane PROKARYOTIC CELLS describes the plasma membrane as a fluid combination of phospholipids, cholesterol, and proteins. Carbohydrates attached to lipids PROKARYOTIC CELLS EUKARYOTIC CELLS (glycolipids) and to proteins (glycoproteins) extend from the outward-facing surface of the Small and simple Large and complex membrane. 0.1 to 5.0µm 10 to 100µm CELL WALL Unicellular Unicellular or Surrounds plant, fungi, bacteria, algae and multicellular archaea cells. Strong structure located just outside of the Nucleus is absent Nucleus is present cells' cell membrane. Plant cell walls are mainly composed of Circular DNA Linear DNA cellulose while fungi cell walls are composed of chitin, glucans and proteins Single haploid Paired diploid and bacterial cell walls are mainly chromosome chromosome composed of peptidoglycan. Lack membrane-bound Has membrane-bound However, all cell walls give the cell rigidity organelles organelles and strength, o ering protection against mechanical stress and limit the entry of Reproduce both Mostly reproduce large molecules that may be toxic to the sexually and asexually sexually cell. Cell division by binary Cell division by mitosis ENDOSYMBIOSIS THEORY fission Hypotheses the origin of organelles within eukaryotic cells. Bacteria and Archaea Plant and animal cells Assumes that once all cells on Earth were cells like humans prokaryotes. ○ At some point, a larger bacteria ingested a smaller bacteria, keeping SIMILARITIES OF PROKARYOTIC AND the membrane intact. EUKARYOTIC CELLS ○ The two bacteria began to work together as a unit, symbiotically, Both have plasma membrane. relying on each other and Both have cytoplasm. reproducing. Both have ribosomes. If the larger cell ingested a cyanobacteria, Both have DNA. that bacteria became a chloroplast and the cell a plant cell. In fact, chloroplast and mitochondria are ANIMAL CELL STRUCTURE the major evidence for the endosymbiotic theory because they both still act like prokaryotes. They have their own DNA compared to the rest of the cell and divide separately from the cell, using binary fission, typical to prokaryotes. However, the chloroplast and mitochondria still need the rest of the cell to live and thrive. Dr. Jennifer Maries Yap ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 CELL DIVISION METAPHASE The chromosomes are aligned at the INTRODUCTION - MITOSIS equatorial region of the nucleus. The phases of the cell cycle. At this stage, the replicate chromosomes, Following mitosis (M), cells enter the G1 which are much shorter and more stage of interphase, initiating a new cycle. condensed, are known as sister chromatids. Cells may become non-dividing (GO) or They are joined together at their central continue through G1, where they become region called centromere. committed to begin DNA synthesis (S) and Closely associated with centromeres are complete the cycle (G2 and M). kinetochores, protein complexes to which Following mitosis, two daughter cells are the spindle fibers are attached to. produced and the cycle begins anew for each cell. ANAPHASE INTERPHASE The sister chromatids are separated and The genetic materials inside the nucleus pulled apart toward the opposite poles. appear as thin, thread-like structures This stage is di erentiated early and late appropriately called chromatin fibers. stages depending on the distance travelled Within the nucleus, can be found 1 to 2 by the chromatids. nucleoli, which are dense, darkly stained bodies formed by several chromosomal materials that code for certain RNA's. Near the nucleus is the centrosome which contains centrioles. TELOPHASE Cleavage furrow, a constriction of the plasma membrane at the region of the equatorial plate, starts to appear. The chromosomes begin to uncoil and assume a threadlike appearance. At this stage the nuclear membrane and the PROPHASE nucleolus start to reappear. The chromatin fibers start to appear as The asters and mitotic spindles disappear. coiled, thickened, condensed structure At late telophase, the cleavage furrow forming chromosomes that are visible becomes more constricted leading to the under the light microscope. formation of 2 daughter cells. Centrioles are seen in the opposite poles. Locate ray-like microtubule bodies called asters radiating around each centrioles and mitotic spindles forming between centrioles. The nuclear membrane begins to disappear as well as the nucleoli CYTOKINESIS It is the division of the cytoplasm, usually occurs along with telophase. Completely separated daughter cells are formed soon after mitosis. Dr. Jennifer Maries Yap ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 MEIOSIS ANIMAL HISTOLOGY & ORGANOLOGY Most cell division results in daughter cells with identical genetic information, DNA. TISSUES The exception is meiosis, a special type of Di erent tissues have di erent structures division that can produce sperm and egg that are suited to their functions cells. Tissues are classified into four main The process is split into meiosis I and categories. meiosis II, and both meiotic divisions have ○ Epithelial multiple phases. ○ Muscle Meiosis I is a type of cell division unique to ○ Connective germ cells, while meiosis II is similar to ○ Nervous mitosis. EPITHELIAL TISSUE Covers the outside of the body and lines the organs and cavities within the body Shape ○ Cuboidal ○ Columnar ○ Squamous Arrangement ○ Simple ○ Stratified ○ Pseudostratified SIMPLE SQUAMOUS Air sacs are the passage of air so it is more likely that it is made up of empty spaces. SIMPLE CUBOIDAL SIMPLE COLUMNAR Dr. Jennifer Maries Yap ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 STRATIFIED SQUAMOUS ADIPOSE CONNECTIVE TISSUE TRANSITIONAL BLOOD HYALINE CARTILAGE CILIATED PSEUDOSTRATIFIED COLUMNAR ELASTIC CARTILAGE CONNECTIVE TISSUE Mainly binds and supports other tissues. Contains sparsely packed cells scattered throughout an extracellular matrix. The matrix consists of fibers in a liquid, jellylike, or solid foundation. AREOLAR/LOOSE CONNECTIVE TISSUE FIBROCARTILAGE DENSE CONNECTIVE TISSUE BONE Dr. Jennifer Maries Yap ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 TYPES OF CONNECTIVE TISSUES SMOOTH MUSCLE COLLAGENOUS FIBERS Provide strength and flexibility. RETICULAR FIBERS Join connective tissue to adjacent tissues. ELASTIC FIBERS Stretch and snap back to their original length. NERVOUS TISSUE CELLS OF CONNECTIVE TISSUES Functions in the receipt, processing, and FIBROBLASTS transmission of information. Secrete the protein of extracellular fibers. NERVOUS TISSUE CONTAINS MACROPHAGES NEURONS Involved in the immune system. Or Nerve Cells that transmit nerve impulses.. MUSCLE TISSUE Responsible for nearly all types of body GLIAL CELLS movement. Or Glia, supports cells. Muscle cells consist of filaments of the proteins actin and myosin, which together enable muscles to contract. It is divided in the vertebrate body into three types. ○ Skeletal Muscle ○ Cardiac Muscle ○ Smooth Muscle SKELETAL MUSCLE ORGANOLOGY CARDIAC MUSCLE Dr. Jennifer Maries Yap ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 FROG BLOOD VESSELS We have di erent parts of the body and then di erent parts of the body are composed of di erent types of tissues that composes the organs. FROG SKIN FROG STOMACH/INTESTINE FROG SPINAL CORD Dr. Jennifer Maries Yap ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 TOAD EXTERNAL ANATOMY Layer where the body of cutaneous glands are situated, thus giving it a spongy ORGAN SYSTEMS appearance. Digestive System STRATUM COMPACTUM Muscular System Integumentary System Inner layer of the dermis. Lymphatic System Consists of layers of white fibrous Endocrine System connective tissue which are compactly Nervous System arranged. Skeletal System Male Reproductive System Female Reproductive System Respiratory System Urinary System Circulatory System CHROMATOPHORES Located at the junction of epidermis and dermis. Contains a row of old black pigment containing melanophores. HISTOLOGY OF THE SKIN DERMIS The skin of the toad, similar to the frog, it is divided into two major layers, the outer epidermis and the inner dermis. ○ These are further subdivided into sublayers. The glands are of two types - the larger, poison glands which possess a thin epithelial wall, and the smaller, more numerous, mucous glands, which have thicker walls. ANATOMICAL DIRECTIONS STRATUM CORNEUM Outermost stratified layer of squamous epithelial tissue of flattened, dead cells. Thin hardened or cornified layer constantly removed when the toad sheds its skin. ○ Ecdysis or molting STRATUM GERMINATIVUM Consisting of living and growing layers of stratified epithelial tissue. STRATUM LAXUM / SPONGIOSUM Outer sublayer immediately below the stratum germinativum. Dr. Jennifer Maries Yap ZOOLOGY LABORATORY LBBBIO8 | Term 1 | 2024 - 2025 THUMB PADS Male ○ The thumb pads of inner fingers are EXTERNAL ANATOMY OF FROG / TOAD enlarged or “swollen”. ○ These are used during amplexus or false copulation. Female ○ The thumb pads of the inner fingers are not “swollen”. SIZE Male ○ Sexually mature male frogs are generally smaller than female. Female ○ Sexually mature female frogs are relatively bigger than males. SEX DETERMINING CHARACTERISTICS (FROGS) VENTRAL VIEW Male ○ The skin on the ventral side of the head near the angles of the jaw has a distinct dark pigmentation due to concentration of pigments. Female ○ Pigments are di used; hence, there are no distinct dark pigmentation. Dr. Jennifer Maries Yap