General Zoology Topics: 1-7 PDF

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This document provides an overview of general zoology, covering topics from history and significance to the work of key figures like Aristotle, William Harvey, and more. It introduces concepts like the binomial nomenclature of organisms and discusses different theories of evolution presented throughout scientific history.

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GENERAL ZOOLOGY TOPIC #01 HISTORY, DEVELOPMENTS, AND SIGNIFICANCE OF ZOOLOGY At the end of this lesson, you will be able to: 1. Discuss the history and branches of zoology; and, 2. Identify the developments in zoology and their uses. SIGNIFICANCE OF ZOOLOGY ...

GENERAL ZOOLOGY TOPIC #01 HISTORY, DEVELOPMENTS, AND SIGNIFICANCE OF ZOOLOGY At the end of this lesson, you will be able to: 1. Discuss the history and branches of zoology; and, 2. Identify the developments in zoology and their uses. SIGNIFICANCE OF ZOOLOGY SIGNIFICANCE OF ZOOLOGY “Students of biological sciences and social sciences can benefit from studying zoology.” SIGNIFICANCE OF ZOOLOGY Through the study of zoology, you can gain an understanding of the natural world and how we can help with conservation. It also offers the opportunity to consider ways to face global challenges such as climate change and food security, trying to find solutions to help both animals and humans alike. SIGNIFICANCE OF ZOOLOGY The study of zoology can lead to the study of animal behavior to a deeper and broader understanding of human psychology. Research on animal behavior has led to numerous discoveries about human behavior, such as Ivan Pavlov's research on classical conditioning. WHO ARE THE GREAT PSYCHOLOGISTS YOU KNOW WHO INCLUDED ANIMALS IN THEIR RESEARCH? WHO AMONG YOU IS EXCITED ABOUT WHAT CAN BE DONE IN LABORATORIES USING ANIMALS AS EXPERIMENT? HISTORY AND DEVELOPMENTS OF ZOOLOGY ARISTOTLE He is known as a Father of Zoology and Biology. More than 2000 years ago, he was able to observe the relationship of flora (plants) and fauna (animals). ARISTOTLE In his time, without microscope, he classified and organized all the organisms as animals and plants. This Scientist known for his primitive method of observation, specially when he wrote his first biology book named, “Aristotle’s Historia Animalium” ARISTOTLE Factors used by Aristotle in his early classification: Red-bloodedness Locomotion Abilities Shape Structure Environment CLAUDIO GALENO DE PÉRGAMO In 2nd century, he’s the most famous scientist that considered that were two (2) types of blood, namely: venous blood from liver that carry nutrients; and arterial blood which is from the heart that forms the vital spirit IBN AL NAFIS In 13th century, he discovered that blood travels from the heart to the lungs although he thought that air is needed to create, what he called “animal spirit”. MIGUEL SERVET After 300 years, in 16th century, he reached the same conclusion as Ibn al Napis and he wrote it theological treatise. These led him to burned at the stake along with most of his written books. WILLIAM HARVEY Known as the “MISUNDERSTOOD GENIUS” On about 17th century, this man ignored all the wisdom from books and research and start his own analysis in snakes and fishes before performing the ultimate experiment in human. WILLIAM HARVEY In 1628, Harvey wrote a book named, “Exercitatio anatomica de motu cordis et sanguinis in animalibus ” which is literally means the Anatomical Studies on the Motion of the Heart and Blood in Animals. WILLIAM HARVEY This book became famous because it contradicted the great Galen’s theory. His research about the blood circulation and the heart led to the promotion of biological research. At the age of 50, he published this masterpiece. THEODORE SCHWANN In 18th century, he begun to make a big impact in the world of biology. He is one of the founding scientist who developed cell theory. He focuses on animal tissues. THEODORE SCHWANN He also discovered pepsin, an protein enzyme that is responsible in digestion. His greatest contribution is the formation of germ theory of alcoholic fermentation. THEODORE SCHWANN He also discovered Schwann cells. He also coined the term metabolism for the chemical changes that happens inside a living tissue. or usually known as CAROLUS LINNAEUS He developed the eight taxonomic hierarchy which he devised includes the: Domain Order Kingdom Family Phylum Genus Class Species TAXONOMIC HIERARCHY or usually known as CAROLUS LINNAEUS He is the Father of Taxonomy or the science of naming using binomial nomenclature (scientific name), and classifying organisms. He devised the classification system which scientist use today in naming newly discovered living organism. WHY DO YOU THINK BINOMIAL NOMENCLATURE IS IMPORTANT? COCONUT - ENGLISH COCO – SPANISH NIYOG – TAGALOG LUBI – CEBUANO NGONGOL – PAMPANGA IING – ITNEG INYOG – IBANAG Cocos nucifera DOMAIN : Eukarya KINGDOM : Animalia PHYLUM : Chordata CLASS : Mammalia ORDER : Carnivora FAMILY : Felidae GENUS : Felis SPECIES : Catus The binomial name consists of a DOMAIN : Eukarya genus name and specific KINGDOM : Animalia epithet. PHYLUM : Chordata The scientific names are always italicized. CLASS : Mammalia The genus name is always ORDER : Carnivora capitalized and is written first; FAMILY : Felidae the specific epithet follows the genus name and is not GENUS : Felis capitalized. SPECIES : Catus There is NO exception to this. Felis catus or usually known as CAROLUS LINNAEUS Linnaeus continued to revise his way of classifying which grew from a slim pamphlet to a multivolume work, as his concepts were modified, more and more specimens were sent to him for classification purposes. CHARLES ROBERT DARWIN The works of Charles Robert Darwin lies mainly on evolution by natural selection. His studies became the foundation of modern evolutionary studies. CONCLUSION WHY DO YOU THINK IT IS IMPORTANT TO UNDERSTAND THE HISTORY AND SIGNIFANCE OF ZOOLOGY? TOPIC #02 THEORIES OF EVOLUTION At the end of this lesson, you will be able to: 1. Discuss the different theories of evolution; and 2. Cite evidences of evolution. JEAN BAPTISTE LAMARCK Use and Disuse Inheritance of Acquired Traits JEAN BAPTISTE LAMARCK Use and Disuse This theory states that when certain organs become specially developed as a result of some environmental need, then that state of development is hereditary and can be passed on to progeny. JEAN BAPTISTE LAMARCK Use and Disuse Lamarck believe that in this way, through many generations, animals such as giraffes could arise from deer-like animals that had to keep stretching their necks to reach high leaves on trees. Theory of Use and Disuse PROPOGATE YES AND PASS TO SPECIFIC PROGENY BODY USE PART OF VERY AN OFTEN? ORGANISM TENDS TO NO DISAPPREAR JEAN BAPTISTE LAMARCK Inheritance of Acquired Traits Lamarck specified that this theory is not to explain heredity but as a model of evolution. He believed that organism could pass on to its offspring their physical characteristics that the parent organism acquired through use or disuse during its lifetime. JEAN BAPTISTE LAMARCK Inheritance of Acquired Traits However, this theory was DISPROVED by many scientists by conducting experiments. Scientist have seen through many examples and observations that changes that occur in an animal during life are not passed on to the animal’s offspring. CHARLES ROBERT DARWIN Theory Of Natural Selection NATURAL SELECTION VS ARTIFICIAL SELECTION Natural selection is any selection process that occurs as a result of an organism's ability to adapt to its surroundings. Artificial selection, on the other hand, is selective breeding that is imposed by an external entity, usually humans, in order to enhance the frequency of desirable features. CHARLES ROBERT DARWIN Theory Of Natural Selection CHARLES ROBERT DARWIN Theory Of Natural Selection All species have different variation, traits and characteristics. Individuals with better adaptive traits are more likely to survive and reproduce. CHARLES ROBERT DARWIN Theory Of Natural Selection The process through which populations of living organisms adapt and change. This variation means that some individuals have traits that are better suited for the environment than others. CHARLES ROBERT DARWIN Theory Of Natural Selection The individual’s adaptive traits will pass to their offspring. Through this process, favorable traits are transmitted through generations. JAMES HUTTON Theory of Geological Change Strong forces change the earth surface due to catastrophe or slow changes. JAMES HUTTON Theory of Geological Change Catastrophism This may happen in relatively short amount of time and it can lead to species mass extinction. It is because of giant natural disasters like meteor shower, volcanic eruption, etc. JAMES HUTTON Theory of Geological Change Uniformitarianism This idea stated that the Earth was formed by slow, uniform ongoing geologic processes, not by sudden catastrophic events. JAMES HUTTON Theory of Geological Change Uniformitarianism One of the interesting things about those events is that they occur today in the same way that they have in the past. Scientists look at today’s geologic events to understand past events CHARLES LYELL Principles of Geology CHARLES LYELL Principles of Geology Lyell is one of the scientists who rejected the theory of catastrophism and supported the theory Hutton. He published his book Principles of Geology in 1830. Lyell believed Hutton was correct about gradually changing processes shaping Earth’s surface. CHARLES LYELL Principles of Geology Generally, Earth's crust took place through countless small changes occurring over vast periods of time, all according to known natural laws. The combined efforts of Lyell and Hutton became the foundation of modern geology. CHARLES LYELL Principles of Geology The examples of this modern principle about geology are: Water erosion Wind erosion Land slide Glaciation Deposition of mud Lava cooling into rocks THOMAS MALTHUS Malthusian Principle THOMAS MALTHUS Malthusian Principle Malthusianism is the idea that population growth is potentially exponential while the growth of the food supply or other resources is linear thus, positive checks must be done to control the use of resources. AMOUNT OF FOOD OR OTHER RESOURCES TIME NUMBER OF AN ORGANISM TIME TIME TIME TIME THOMAS MALTHUS Malthusian Principle The theory propounded by Malthus can be summed up in the following propositions: 1. Population is necessarily limited by the means of subsistence (e.g. food). In other words, the size of population is determined by the availability of food. The greater the food production, the greater the size of the population which can be sustained. THOMAS MALTHUS Malthusian Principle The theory propounded by Malthus can be summed up in the following propositions: 2. Population increases in geometric progression or by multiples and food production increases in arithmetic progression or by addition. THOMAS MALTHUS Malthusian Principle The theory propounded by Malthus can be summed up in the following propositions: 3. Population always increases when the means of subsistence increase unless prevented by some powerful checks. (natural or political) THOMAS MALTHUS Malthusian Principle The theory propounded by Malthus can be summed up in the following propositions: 4. Two types of check can keep population on a level. The preventive and positive checks. THOMAS MALTHUS Malthusian Principle The preventive and positive checks. POSITIVE PREVENTIVE STARVATION ABSTAIN FROM SEX WAR PROMOTE LATE MARRIAGE DISEASE USING CONTRACEPTIVES Be guided with these terms! Fossils - preserved remains or impressions of ancient organisms. This includes bones, shells, exoskeletons etc. Homologous -similar structures but not in function. Analogous- structures that are anatomically dissimilar but same in function. Vestigial- structure that is no longer functional. In humans this includes, muscle of the ear, wisdom tooth, appendix, and tail bone. HOMOLOGOUS STRUCTURES ANALOGOUS STRUCTURES TOPIC #03 EXPLORING ECOLOGY At the end of this lesson, you will be able to: 1. Discuss the different levels of ecological study; and 2. Differentiate biotic and abiotic factors. WHAT IS ECOLOGY? ECOLOGY? Branch of biology that deals with the relations of organisms to one another and to their physical surroundings. Ecology is defined as the study of how living organisms on our planet interact with each other. CHARACTERISTICS OF LIVING ORGANISMS Characteristics of Living Organisms 1. Cellular organization - living things exhibit a high level of organization. All multicellular organisms are composed of cell and cell products. (cells – tissues – organ – system – organism) Characteristics of Living Organisms 2. Homeostasis It is the maintenance of a constant but dynamic internal environment within the body of organism. Characteristics of Living Organisms 3. Adaptation It is the ability of the organism to adjust to become fit to the changes in the environmental condition. 4. Reproduction It is necessary to perpetuate life. Characteristics of Living Organisms 5. Growth and development All living things increase in size due to cell division 6. Constant energy requirement Living things need energy to sustain life, hence energy is very essential to life Characteristics of Living Organisms 7. Responsiveness/ Irritability It is the ability of the organisms to respond to the various stimuli from the environment. HOW OUR PLANET REMAINS ITS ABILITY TO SUSTAIN LIFE? BIOTIC AND ABIOTIC FACTORS BIOTIC FACTORS A biotic factor is a living organism that shapes its environment. Example in freshwater ecosystem, it might include aquatic plants, fish, amphibians, and algae. ABIOTIC FACTORS An abiotic factor is a non-living part of an ecosystem that shapes its environment. In a terrestrial ecosystem, examples might include temperature, light, water, rock and soil, and atmosphere. LEVELS OF ECOLOGY ORGANISM POPULATION COMMUNITY ECOSYSTEM BIOME BIOME BIOSPHERE LEVELS OF ECOLOGY ORGANISM 1 specific species POPULATION Group of the same species COMMUNITY Population in an area Community with abiotic ECOSYSTEM factors Ecosystem with the same BIOME climate (tundra, dessert, rain forest) CONCLUSION TOPIC #04 TAXONOMY (Phylum) Mollusca, Porifera, Cnidaria, Platyhelminthes and Nematoda OBJECTIVES At the end of this lesson, you will be able to: 1. differentiate phylum according to their distinctive characteristic; and, 2. list down animals according to their phyla. PHYLUM: Mollusca Gastropods, Bivalves & Cephalopods PHYLUM: Mollusca ✓ They are soft-bodied animals that usually have an internal or external shell. ✓ Ex. Clams, squid, octopus, mussels, sea slug. ✓ They have a free swimming larval stage called a trochophore. PHYLUM: Mollusca BODY PLAN – 4 PARTS 1. foot – used for crawling, burrowing 2. mantle – thin layer of tissue that covers organs 3. shell – made by glands in the mantle that secrete calcium carbonate 4. visceral mass – guts (internal organs) PHYLUM: Mollusca FEEDING By the used of radula – ribbon of teeth Others are filter feeders using an incurrent and excurrent siphon FEEDING PHYLUM: Mollusca RESPIRATION AND CIRCULATION Respiration – GILLS Circulation - OPEN CIRCULATORY SYSTEM – heart and open sinuses. PHYLUM: Mollusca RESPONSE AND MOVEMENT Response ✓ Clams- simple nervous system ✓ Octopus – brains, complex behavior. Octopi and squid can open jars for reward or to avoid punishment Movement – mucus with the foot/muscle or jet propulsion for the octopus. PHYLUM: Mollusca REPRODUCTION Reproduction ✓ Usually external fertilization in the water. ✓ Some tentacled mollusks do internal fertilization. ✓ Some can be hermaphrodites. 3 MAIN GROUPS OF PHYLUM MOLLUSCA 1. Gastropods – shell-less or single shelled mollusks that move by using a muscular foot. The examples are: ✓ Sea hares – can squirt ink at predators ✓ Nudibranches – sea slugs, have chemicals in their bodies that taste bad. Can recycle nematocysts from cnidarians they eat. Sea hares Nudibranches 3 MAIN GROUPS OF PHYLUM MOLLUSCA 2. Bivalves – two shells held together by two powerful muscles. Clams, oysters, mussels and scallops. ✓ Scallops can flap their shells to move when threatened. ✓ Filter water over gills use mucus and cilia on gills to trap food particles. 3 MAIN GROUPS OF PHYLUM MOLLUSCA 3. Cephalopods – “head-footed”. Soft bodied. The head is attached to a single foot. The foot is divided into tentacles or arms. ✓ squid, octopus, nautilus, cuttlefish. They move by jet propulsion. ✓ Many have an ink sac to distract potential predators. ✓ They have a pen for a “backbone.” Nautilus Cuttlefish PHYLUM: Porifera Sponges PHYLUM: Porifera CHARACTERISTICS OF SPONGES 1. Contain pores (holes) to get food. 2. Adults are sessile (don’t move). 3. Are filter feeders – move water containing food in their pores & out a large hole in the top (an Osculum). 4. Body is asymmetrical & sac-like. PHYLUM: Porifera CHARACTERISTICS OF SPONGES 5. Are multicellular. 6. Are heterotrophic, have NO cell walls, & contain few specialized cells. 7. Have NO mouth, gut, specialized tissues, or organs. PHYLUM: Porifera CHARACTERISTICS OF SPONGES 5. Have skeletons. 6. Reproduce sexually or asexually. PHYLUM: Porifera STRUCTURE OF SPONGES ✓ Sponges have a simple body form. ✓ They depend on a current of water for everything, since they’re sessile. ✓ Body forms a wall around center cavity. Wall contains pores, to allow water flow into the center cavity. PHYLUM: Porifera STRUCTURE 1. Collar cells (Choanocytes) – digest food particles & contain flagella that move the water current through the sponge. 2. Osculum – large hole in the top of the sponge that allows water to exit the central cavity. PHYLUM: Porifera STRUCTURE 3. Spicule – thin, spiny structures that form the simple skeleton. 4. Amebocytes – cells that build spicules, digest food, & transport particles to cells. 5. Spongin – fibers of protein that make up softer sponges PHYLUM: Porifera REPRODUCTION Sexual reproduction – eggs are stored inside the walls of female sponges. Male sponges release sperm into the water. Sperm enter the female sponge through the water current & her cells carry the sperm to the eggs to be fertilized (internal fertilization). PHYLUM: Porifera REPRODUCTION Asexual reproduction – is either budding or regeneration. Gemmules – sphere shaped collections of amebocytes surrounded by a tough layer of spicules. Can survive harsh conditions & later grow into new sponges. PHYLUM: Cnidaria Jellyfish, Sea anemones, and Hydra PHYLUM: Cnidaria The phylum name comes from Cnidaria, the Greek word for nettle, a plant that has stinging hairs. PHYLUM: Cnidaria ✓ Exhibit radial or biradial symmetry. ✓ Are all aquatic (typically marine, but some freshwater). ✓ Are sessile, free-floating, or weak swimming. ✓ Have a tissue-level organization. ✓ Have a primitive nervous system. ✓ Have stinging cells. PHYLUM: Cnidaria ✓ Cnidarian bodies are organized around the gastrovascular cavity, where digestion takes place. ✓ Two layers of cells: gastrodermis (lining the digestive tract) and epidermis (outer layer) ✓ Mesoglea: jelly substance in between the two cell layers. Medusa Polyp PHYLUM: Cnidaria REPRODUCTION Sexual reproduction: gametes are shed directly into the water. Asexual reproduction: usually by budding, some by fission. PHYLUM: Cnidaria REPRODUCTION PHYLUM: Cnidaria LIFE CYCLE Cnidarians generally alternate between sessile polyps that reproduce asexually and swimming medusae that reproduce sexually. One of these stages is missing in many forms of other organism. PHYLUM: Cnidaria FOUR IMPORTANT CNIDARIAN CLASSES 1. CLASS HYDROZOA ✓ Mostly marine ✓ Alteration of generation (polyp and medusa stages) is usually exhibited ✓ Includes hydroids, fire corals, and Portugese man-of-war HYDROZOAN: HYDRA PHYLUM: Cnidaria FOUR IMPORTANT CNIDARIAN CLASSES 2. CLASS SCYPHOZOA ✓ Dominant stage is the medusa ✓ Polyp is absent or reduced ✓ Cup-shaped umbrellas ✓ Includes true jellyfish SCYPHOZOA: AURELIA LABIATA PHYLUM: Cnidaria FOUR IMPORTANT CNIDARIAN CLASSES 3. CLASS CUBOZOA ✓ Like jellyfishes, but they have cubical umbrellas. ✓ Some may deliver fatal stings. ✓ Includes the box jelly, one of the 10 most venomous organisms on earth. Cubozoans PHYLUM: Cnidaria FOUR IMPORTANT CNIDARIAN CLASSES 4. CLASS ANTHOZOA ✓ Polyps with a flowerlike appearance ✓ NO medusa stage ✓ All marine, found all over the world ✓ Includes sea anemones, corals, sea fans, and sea whips. ANTHOZOANS: CORALS Anthozoans: Anemones ANTHOZOANS: ANEMONES PHYLUM: Platyhelminthes Flatworms PHYLUM: Platyhelminthes 4 Principal Types Of Flatworms Divided Into 4 Taxonomic Groups 1. Class Turbellaria >3,000 free-living species some commensal, a few parasitic forms Aquatic, few on land Body architecture adapted to a free-living lifestyle. PHYLUM: Platyhelminthes 4 Principal Types Of Flatworms Divided Into 4 Taxonomic Groups 2. Class Monogenea 400 spp mostly ectoparasites of fish, amphibians that Feed on blood, mucus, etc. Anterior and posterior ends for clinging, but life cycle remains simple, with a single free living larval stage. Class Monogenea PHYLUM: Platyhelminthes 4 Principal Types Of Flatworms Divided Into 4 Taxonomic Groups 3. Class Trematoda: flukes > 6000 spp of endoparasites (liver, lungs, blood, muscles) Body and life cycle adapted to parasitic existence. > 6000 spp of endoparasites (liver, lungs, blood, muscles) Body and life cycle adapted to parasitic existence. Oral sucker oral sucker ventral sucker Ventral sucker Class Trematoda: Schistosome life cycles are unusual in several ways Separate sexes: dioecious Hydatidosis of the Liver Cerebral Hydatidosis PHYLUM: Platyhelminthes 4 Principal Types Of Flatworms Divided Into 4 Taxonomic Groups 4. Class Cestoda: tapeworms > 3500 spp of endoparsites, almost all intestinal parasites with highly specialized body and life cycle. 9 ft tapeworm from human host. Largest in sperm whale was over 30 meters long Class Cestoda: tapeworms > 3500 spp of endoparsites, almost all intestinal parasites SCOLEX with highly specialized body and life cycle. PHYLUM: Nematoda Roundworms PHYLUM: Nematoda ✓ Common name: round worms ✓ >20,000 species. ✓ Mostly widespread and abundant of all metazoans ✓ 90,000 worms in a decomposing apple. ✓ Marine and freshwater benthos, soil, parasites on plants and animals PHYLUM: Nematoda ✓ Most are parasitic ✓ Smaller than tapeworms with a thick outer covering that keeps them from being digested ✓ Tapered at both ends PHYLUM: Nematoda ✓ Free-living species have well developed sensory organs ✓ Some species are parasitic to plants and fungi ✓ Can form symbiotic relationships with bacteria ✓ 50 species are human parasites (including hookworm and pinworm) PHYLUM: Nematoda Muscular and Digestive Systems of Roundworms ✓ Have a pseudocoelom and 2 body openings (mouth and anus) ✓ Simplest animals with a tubelike digestive system Have pairs of lengthwise muscles ✓ Lack circular muscles ✓ Move in a thrashing motion PHYLUM: Nematoda Roundworms infect humans by several methods Can go through the host’s: ✓ Digestive tract (Ascarsis) ✓ Through the skin (Hookworms) ✓ Through undercooked food (pigs infected with Trichinella) Ascaris lumbricoides Ascaris lumbricoides Hookworm infection Hookworm infection PHYLUM: Nematoda Roundworm parasites of other organisms ✓ Nematodes infect pine trees, cereal crops and food plants ✓ Attracted to plant roots, soil and root crops ✓ 1200 species cause disease in plants ✓ Soil nematodes invade roots for food TOPIC #6 WHAT MAKES UP AN ATOM At the end of this lesson, you will be able to: 1. discuss the three sub atomic particles; and, 2. determine number of protons, electrons, and neutrons of an atom. 5th CENTURY BC DEMOCRITUS Greek Philosopher who suggested everything was made of two things – empty space and “atomos” Atomos – Greek word for “uncuttable” or indivisible 5th CENTURY BC DEMOCRITUS 2 MAIN IDEAS Atoms are the smallest possible particle of matter. There are different types of atoms for each material. LATER THAN 5th CENTURY BC ARISTOTLE and others Also a Greek Philosopher who conclude that matter consisted of various combinations of the “elements” and could be infinitely divided. - FIRE, EARTH, AIR, AND WATER - Aristotle believed that logical thought and observation, alone, was enough to explain the world and rules of motion. 2000 YEARS AFTER ARISTOTLE JOHN DALTON British scientist who claimed that atoms of different elements vary in size and mass, and indeed this claim is the cardinal feature of his atomic theory. 2000 YEARS AFTER ARISTOTLE JOHN DALTON Revolutionized chemistry by creating the atomic theory. 1807 JOHN DALTON DALTON’S ATOMIC THEORY 1. All matter consists of tiny particles called atoms. Dalton and others imagined the atoms that composed all matter as tiny, solid spheres in various stages of motion. 1807 JOHN DALTON DALTON’S ATOMIC THEORY 2. Atoms are indestructible and unchangeable. Atoms of an element cannot be created, destroyed, divided into smaller pieces, or transformed into atoms of another element. Dalton based this hypothesis on the 1807 JOHN DALTON DALTON’S ATOMIC THEORY 3. Elements are characterized by the weight of their atoms. Dalton suggested that all atoms of the same element have identical weights. Therefore, every single atom of an element such as oxygen is identical to every other oxygen atom. 1807 JOHN DALTON DALTON’S ATOMIC THEORY 4. In chemical reactions, atoms combine in small, whole-number ratios. Experiments that Dalton and others performed indicated that chemical reactions proceed according to atom to atom ratios which were precise and well-defined. 1807 JOHN DALTON DALTON’S ATOMIC THEORY 5. When elements react, their atoms may combine in more than one whole-number ratio. Dalton used this assumption to explain why the ratios of two elements in various compounds, such as oxygen and nitrogen in nitrogen oxides, differed by multiples of each other. 1807 JOHN DALTON DALTON’S ATOMIC THEORY 1. All matter is made of atoms. 2. Atoms neither be created nor destroyed. 3. Atoms of one element are all the same. 4. Compounds form by combining atoms. 1807 JOHN DALTON Dalton’s Early Atomic Model “Billiard Ball” model He envisioned atoms as solid, hard spheres, like billiard balls, so he used wooden balls to model them. SPECIAL CONTRIBUTION 1830 - Michael Faraday He develop 2 laws of electrochemistry. 1. The amount of chemical change produced by current at an electrode-electrolyte boundary is proportional to the quantity of electricity used and; 2. the amounts of chemical changes produced by the same quantity of electricity in different substances are proportional to their equivalent weights. SPECIAL CONTRIBUTION 1879 - Sir William Crookes He studied the effects of sending an electric current through a gas in a sealed tube. 1895 - Wilhelm Roentgen We know them today as x-rays which are part of the electromagnetic spectrum. SPECIAL CONTRIBUTION 1896 - Henri Bequerel Bequerel had discovered radioactivity. The radiation emitted by the uranium shared certain properties with x-rays and light. These rays were named alpha, beta, and gamma by Ernest Rutherford. 1897 JOSEPH JOHN THOMSON Discovered the electron. He was the first scientist to show the atom was made of even smaller things. He demonstrated that cathode rays were negatively charged. THOMSON’S EXPERIMENT Voltage source - + Vacuum tube Metal Disks THOMSON’S EXPERIMENT Voltage source - + THOMSON’S EXPERIMENT Voltage source - + THOMSON’S EXPERIMENT Voltage source - + Passing an electric current makes a beam appear to move from the negative to the positive end THOMSON’S EXPERIMENT Voltage source - + Passing an electric current makes a beam appear to move from the negative to the positive end THOMSON’S EXPERIMENT Voltage source - + Passing an electric current makes a beam appear to move from the negative to the positive end THOMSON’S EXPERIMENT Voltage source - + Passing an electric current makes a beam appear to move from the negative to the positive end THOMSON’S EXPERIMENT Voltage source By adding an electric field THOMSON’S EXPERIMENT Voltage source + - By adding an electric field THOMSON’S EXPERIMENT Voltage source + - By adding an electric field THOMSON’S EXPERIMENT Voltage source + - By adding an electric field THOMSON’S EXPERIMENT Voltage source + - By adding an electric field THOMSON’S EXPERIMENT Voltage source + - By adding an electric field THOMSON’S EXPERIMENT Voltage source + - - Adding an electric field cause the beam to move toward the positive plate. Thomson concluded the beam was made of negative moving pieces. 1897 “PLUM PUDDING”MODEL 1911 ERNEST RUTHERFORD He is a former student of J.J. Thomson, proved Thomson's plum pudding structure is incorrect. 1911 ERNEST RUTHERFORD Rutherford with the assistance of Ernest Marsden and Hans Geiger performed a series of experiments using alpha particles. 1911 ERNEST RUTHERFORD NON-DEFLECTED Positively charged CIRCULAR ZINC- PARTICLE alpha-particles were SULPHIDE directed at a piece of thin gold foil. GOLD FOIL ALPHA RAYS DEFLECTED PARTICLE RADIOACTIVE SOURCE 1911 ERNEST RUTHERFORD Rutherford predicted the alpha particles would pass straight through the gold foil. That’s not what happened. 1911 ERNEST RUTHERFORD RUTHERFORD’S CONCLUSION 1. The atom is mostly empty space. 2. There is a small, dense center with a positive charge. 3. Rutherford discovered the nucleus in atoms 1913 NEILS BOHR He is a student of Rutherford's, developed a new model of the atom. Expanded Rutherford nuclear model He used the work of Plank and Einstein as the basis to stipulate that electrons orbits around the nucleus. This model is patterned on the solar system and is known as the planetary model. 1926 ERWIN SCHRÖDINGER An Austrian physicist that took the Bohr atom model one step further. He generated a mathematical model for the distribution of electrons in an atom. This mathematical equation leads to the location of electrons in an atom or the direction of electron where it goes. 1926 ERWIN SCHRÖDINGER This atomic model is known as the quantum mechanical model of the atom. The quantum mechanical model does not define the exact path of an electron, but rather, predicts the odds of the location of the electron. 1926 ERWIN SCHRÖDINGER 1927 WERNER HEISENBERG “Uncertainty Principle” “It was impossible to determined the both the exact position and speed of electron as they move around the atom” It means that the electrons cannot be pin-pointed but exist on a possible location using the Schrödinger’ s equation. 1932 JAMES CHADWICK Proves the existence of neutrons. He used the new method of detecting particles emitted by radioactive elements developed by Irene Jolio Curie. The essential nature of atomic nucleus was established with the discovery of neutron. 1932 JAMES CHADWICK He determine that there is a new elementary particle distinct from the proton and led to the discovery of nuclear power and weapon by the end of WWII. 1932 JAMES CHADWICK 21 ST CENTURY MODERN ATOMIC THEORY This time, scientist formulated that atom of one element are the same, and atom with different elements are different. Also, atom of the same elements that is atom with the same number of proton with different numbers of neutrons are called ISOTOPES. Elements can be categorized as metals, nonmetals, or metalloids. Metals are good conductors of heat and electricity. Nonmetals are poor conductors of heat or electricity. Metalloids have intermediate properties. A vertical column is known as a group. Group 8A elements (He, Ne, Ar, Kr, Xe, Rn) are called the noble gases. The periodic table is a chart in which elements having similar chemical and physical properties are grouped together. ATOMIC NUMBER: 8 ATOMIC MASS: ?? MASS NUMBER: ?? # OF PROTON: ?? # OF NEUTRONS: ?? # OF ELECTRONS: ?? CHARGE: 0 ATOMIC NUMBER (Z) = # OF PROTON ATOMIC MASS = (if indicated just copy) MASS NUMBER (A) = # OF PROTONS + # OF NEUTRONS # OF PROTONS = ATOMIC NUMBER (Z) # OF NEUTRONS = MASS NUMBER (A) - ATOMIC NUMBER (Z) IF NEUTRAL: (P=e); # OF ELECTRONS = IF POSITIVE CHARGE: (P – (positive charge) ); IF NEGATIVE CHARGE: (P + (negative charge) ); IF LOOSEN AN ELECTRON: (+) positive charge; CHARGE = IF GAINS AN ELECTRON: (-) negative charge; Or PROTON – ELECTONS = CHARGE ATOMIC NUMBER: 8 ATOMIC MASS: ?? MASS NUMBER: ?? # OF PROTON: ?? # OF NEUTRONS: ?? # OF ELECTRONS: ?? CHARGE: 0 ATOMIC NUMBER: 8 ATOMIC MASS: 15.9994 MASS NUMBER: 16 # OF PROTON: 8 # OF NEUTRONS: 8 # OF ELECTRONS: 8 CHARGE: 0 ATOMIC NUMBER: 2 ATOMIC MASS: 4.0026 MASS NUMBER: 4 # OF PROTON: 2 # OF NEUTRONS: 2 # OF ELECTRONS: 2 CHARGE: 0 ATOMIC NUMBER: 30 ATOMIC MASS: 65.38 MASS NUMBER: 65 # OF PROTON: 30 # OF NEUTRONS: 35 # OF ELECTRONS: 30 CHARGE: 0 ATOMIC NUMBER: 92 ATOMIC MASS: 238.029 MASS NUMBER: 238 # OF PROTON: 92 # OF NEUTRONS: 146 # OF ELECTRONS: 92 CHARGE: 0 TOPIC #7 THE CELL At the end of this lesson, you will be able to: 1. differentiate prokaryotic and eukaryotic cells; and, 2. explain the function of each cell organelle. THE HISTORY OF THE CELL THEORY MARCELO MALPIGHI An Italian doctor and naturalist, born in 1628. He is considered to be the “FATHER OF MICROSCOPY” as he carried out many observations of tissues taken from living things using simple microscopes. He died in Rome in 1694. Malpighi made many drawings of his observations, like the ones in the engraving on the left. In this Malpighi drawing some of the observations he made of plant tissues can be seen. ANTON VAN LEEUWENHOEK A Dutch scientist and tradesman, born in 1632. He died in 1723. He manufactured many microscopes and used them to observe microorganisms. The engraving on the left shows some drawings of the microorganisms that Leeuwenhoek observed using microscopes he made himself. ROBERT HOOKE An English scientist, born in 1635. He died in 1703. In 1665, he studied a sheet of cork with a simple microscope like the one you see in the next picture. The engraving on the left shows one of Hooke’s drawings of his observations of a sheet of cork. When he saw the small, honeycomb-like compartments on the sheet, Hooke called them “cells” (from the Latin word for small room). ROBERT BROWN A Scottish botanist, born in 1773. He died in 1858. Thanks to developments in microscopes, he was able to observe the inside of plant cells in more detail. Brown discovered that there was a structure in plant cells: he called it the “nucleus.” Scientists would later discover that this structure is present in all eukaryotic cells. MATTHIAS SCHLEIDEN A German botanist (1804-1881) THEODOR SCHWANN A German physiologist and anatomist (1810-1882) RUDOLF VIRCHOW A German doctor (1821-1902) In 1937, Schleiden came to the conclusion that the cell is the unit of structure in plants. In other words, that all plants are made of cells. A year later, Schwann concluded that this is also true for animals. In other words, that all animals are also made of cells. Based on both scientists’ findings, the first principle of the cell theory was developed: “The cell is the unit of structure of living organisms.” RUDOLF VIRCHOW Virchow studied the physiology of cells and concluded that every cell carried out the three vital functions. RUDOLF VIRCHOW Virchow’s work led to the completion of the other two principles of the cell theory: “The cell is the unit of function of living organisms.” “All cells come from preexisting cells.” THE CELL THEORY 1. The cell is the basic unit of life in all living things. 2. All organisms are made of cells. 3. All cells come from preexisting cells. TWO TYPES OF CELLS TWO TYPES OF CELLS PROKARYOTIC CELLS Have NO membrane-covered DNA. Have NO membrane-covered organelles. Have circular DNA. Belongs to Kingdom Monera. PROKARYOTIC CELLS TWO TYPES OF CELLS EUKARYOTIC CELLS Have a TRUE nucleus. Have a membrane-covered organelles Have linear DNA. DIFFERENT PARTS AND FUNCTIONS OF A EUKARYOTIC CELL CELL MEMBRANE Outer layer of cell Allows nutrients into the cell and wastes outside of the cell “Gate into the city” Cell Membrane CYTOPLASM Cytoplasm a jelly-like fluid contained in the cell that holds the organelles. THE NUCLEUS DNA The control center of the cell Contains the Cell’s DNA Nucleolus Nuclear Membrane MITOCHONDRIA Power center of cell Outer Membrane Provides the energy the cell needs to move, divide, etc. Inner Membrane RIBOSOMES Site where proteins are made. Cell parts are made of proteins. ENDOPLASMIC RETICULUM Transportation system of cell Rough ER- ribosome's attached Smooth ER- no ribosome's GOLGI COMPLEX Packaging house of cell Packages, processes, and ships out the stuff the cell makes. LYSOSOMES Digests food particles and cell parts or “Garbage men”. Protects cell by digesting foreign invaders or “Police men”. VACUOLE Stores water, food & wastes. CELL WALL Found only in plant cells Protects and supports the cell CHLOROPLASTS Found only in plant cells. Contains chlorophyll (makes plants green) Where photosynthesis takes place GENERAL ZOOLOGY

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