Earth and Life Science PDF

EARTH AND LIFE SCIENCE ——— LESSON 1 : THE ORIGIN OF LIFE —— THEORIES OF THE ORIGIN OF LIFE : — SPONTANEOUS GENERATION Life arises from non-living matter. — BIOGENESIS Life originates from pre-existing life. — PANSPERMIA Life originated elsewhere and was transported to Earth. — SPECI...

EARTH AND LIFE SCIENCE ——— LESSON 1 : THE ORIGIN OF LIFE —— THEORIES OF THE ORIGIN OF LIFE : — SPONTANEOUS GENERATION Life arises from non-living matter. — BIOGENESIS Life originates from pre-existing life. — PANSPERMIA Life originated elsewhere and was transported to Earth. — SPECIAL CREATION Life was created by a supernatural being. — THE PRIMORDIAL SOUP THEORY Proposed by Alexander Oparin and John Haldane. Life started in a "soup" of organic molecules formed by energy from lightning interacting with atmospheric chemicals. The early Earth's oceans were filled with simple organic molecules (CHNOPS) essential for life. These molecules are self-assembled into living cells, starting with amino acids —— CLASSICAL EXPERIMENTS SUPPORTING THE PRIMORDIAL SOUP THEORY : — ELECTRICAL DISCHARGE EXPERIMENT : MILLER UREY Simulated the early Earth's atmosphere with gases like methane, ammonia, water, and hydrogen. — THERMAL SYNTHESIS EXPERIMENT : SIDNEY FOX Demonstrated the formation of proteinoid microspheres (protocells) by heating amino acids. — PROTOCELL EXPERIMENT : JACK SZOSTACK Investigated the formation of protocells from nucleic acids and lipids, suggesting that early life forms with a single RNA gene could have evolved. EARLY LIFE FORMS The first evidence of life dates back to 3.5 billion years ago. The earliest life forms were prokaryotes, single-celled organisms without a nucleus. Cyanobacteria, the first photosynthetic organisms, played a crucial role in oxygenating the Earth's atmosphere. EVOLUTION OF MULTICELLULAR ORGANISMS : Multicellular organisms evolved from unicellular eukaryotes. Single eukaryotic cells formed colonies through association, leading to cell specialization and the development of multicellular organisms. Fossil evidence supports the evolution of life over time, with organisms adapting to their environment for survival. ——— LESSON 2 : UNIFYING THEME OF LIFE — ORGANIZATION Life is organized from the atomic level to the biosphere level. Cells are the basic unit of life, forming tissues, organs, organ systems, and ultimately organisms. Organisms interact within populations, communities, ecosystems, and the biosphere. — ADAPTATION AND EVOLUTION Evolution explains the unity and diversity of life. Organisms adapt to their environment to survive, and those with favorable traits are more likely to reproduce. Natural selection drives this process, leading to changes in species over time. — REGULATION AND HOMEOSTASIS Organisms maintain internal balance (homeostasis) to survive in diverse environments. Examples include maintaining body temperature and blood glucose levels. — ENERGY PROCESSING Living organisms obtain and process energy. Autotrophs produce their own food (e.g., plants through photosynthesis). Heterotrophs obtain energy by consuming other organisms. — GROWTH AND DEVELOPMENT Organisms follow a pattern of growth and development based on their genetic code. Cells divide and differentiate, leading to increased size and complexity. — RESPONSE TO STIMULI Living organisms respond to changes in their environment (stimuli). Responses can be in various forms, such as movement, contraction, or changes in behavior. — REPRODUCTION AND HEREDITY Reproduction ensures the survival of species. Asexual reproduction involves a single parent, while sexual reproduction involves two parents. Heredity is the passing of traits from parents to offspring through genes. — DIVERSITY AND UNITY All living beings are systems, with a unity that is greater than the sum of its parts. Diversity of life arises from different environments and evolutionary pressures. — LIVING THINGS ARE MADE OF CELLS Cells are the fundamental building blocks of all living organisms. Viruses are nonliving entities that require living cells to replicate. ——— LESSON 3 : ANIMAL REPRODUCTION —— ASEXUAL REPRODUCTION This type of reproduction does not require two parents. The offspring is an exact copy of the parent. Common forms include fission, fragmentation, and budding. 1. FISSION The parent divides in half, forming two individuals. 2. FRAGMENTATION Breaking of body parts followed by regeneration. 3. BUDDING An outgrowth (bud) develops from the parent and eventually separates to become a new individual. —— SEXUAL REPRODUCTION - Requires two parents to produce offspring. - The combination of genes from both parents increases species variation. - Fertilization, the union of egg and sperm cells, can happen internally or externally. — EXTERNAL FERTILIZATION - The union of egg and sperm occurs outside the female reproductive tract. - Common in bony fish and amphibians. — INTERNAL FERTILIZATION - The union of egg and sperm occurs within the female reproductive tract. - Offspring can be produced in three ways: oviparity, ovoviviparity, and viviparity. 1. OVIPARITY Eggs are fertilized internally but develop outside the mother's body. 2. OVOVIVIPARITY Eggs are fertilized internally and develop inside the mother, receiving nourishment from the yolk. 3. VIVIPARITY Eggs develop internally and receive nourishment directly from the mother's blood through the placenta. ——— LESSON 4 : GENETIC ENGINEERING — GENETIC ENGINEERING Altering an organism's DNA to create new species. — GENETIC MODIFIED ORGANISM Organisms resulting from genetic engineering, also known as transgenic organisms. — TECHNIQUES OF GENETIC ENGINEERING Artificial Selection (Breeding): Selective Breeding: Selecting organisms with desired traits for mating. Hybridization: Breeding different organisms to combine traits. Inbreeding: Breeding closely related organisms to maintain desired traits. Cloning: Creating a genetically identical copy of an organism. Natural Cloning: Identical twins, parthenogenesis, and asexual reproduction. Artificial Cloning: Techniques like somatic cell nuclear transfer (Dolly the sheep). Gene Splicing: Inserting specific gene sequences into the genome of another organism. Recombinant DNA Technology: Using vectors like bacteria or viruses to transfer genetic information. APPLICATIONS OF GENETIC ENGINEERING Genetically Modified Bacteria: Escherichia coli for producing synthetic human insulin. Cyanobacteria for producing bioplastic. Genetically Modified Plants: Bt corn for pest resistance. Banana vaccine for hepatitis virus. Golden rice for betacarotene production. Genetically Modified Animals: Bioluminescent animals for cell identification and disease detection. Fast-growing salmon for increased growth hormones. — ETHICAL CONSIDERATIONS OF GMO's BENEFITS : Increased production, pest resistance, reduced pesticide use, improved nutritional content, disease detection, and enhanced colors. RISKS : Allergic reactions, production of toxins, and disruption of biodiversity. — SAFETY OF GMO's Extensive research and testing have shown that GMO foods are safe for human consumption. The National Academies of Science, Engineering, and Medicine (NAS) concluded in 2016 that GMOs are safe to eat. — HISTORY OF GMO's Early Stages: Artificial selection practiced by ancestors, dating back to 7,800 BCE. Modern Era: 1973: First genetically engineered (GE) product invented. 1975: Asilomar Conference established guidelines for GE experiments. 1990s: Genetically modified foods introduced to markets. 2000s: Continued development and commercialization of GMOs. — OTHER INFORMATION ABOUT GMO's Restriction Enzymes: Enzymes that cut DNA at specific nucleotide sequences. DNA Ligase: An enzyme that joins DNA fragments together. Plasmids: Circular DNA molecules found in bacteria, used as vectors in genetic engineering. Transformation: The process of introducing foreign DNA into a cell. T-DNA: A segment of DNA in the Ti plasmid of Agrobacterium tumefaciens, used for gene transfer into plants. Cry1Ab Toxin: A protein produced by Bacillus thuringiensis, lethal to certain insect larvae. ——— LESSON 5 : ORGAN SYSTEM — DIGESTIVE SYSTEM Major Organs: Mouth, tongue, teeth, salivary glands, pharynx, esophagus, stomach, liver and gallbladder, pancreas, small and large intestines. Receives, breaks down, and absorbs food. Eliminates unabsorbed material. Nutrient Absorption: Digestion: Mechanical and chemical processes break down food into smaller, soluble forms. Absorption: Nutrients pass through the intestinal walls into the bloodstream. Metabolism: Nutrients are converted into energy for repair, growth, and development. Anabolism: Building new substances. Catabolism: Breaking down substances. — RESPIRATORY SYSTEM Major Organs: Nasal cavity, pharynx, larynx, trachea, bronchi, lungs. Intake and output of air. Exchange of gases between air and blood. Lungs: The primary organs of respiration in mammals, where oxygen is absorbed and carbon dioxide is released. Gills: Used by aquatic animals to extract dissolved oxygen from water. Tracheal System: Found in insects, allowing direct diffusion of oxygen and carbon dioxide to and from cells. Skin: Used by amphibians, earthworms, and some turtles for cutaneous respiration. — SKELETAL SYSTEM Major Organs: Bones, ligaments, cartilages. Support. Protection. Movement. Storage. Hematopoiesis (blood cell production). The skeletal system provides structural support, protects vital organs, facilitates movement, stores minerals, and produces blood cells. — CARDIOVASCULAR SYSTEM Major Organs: Heart, arteries, capillaries, veins. Major Functions: Move blood through vessels. Transport substances throughout the body. The cardiovascular system is a closed circulatory system that transports oxygen, nutrients, hormones, and other essential substances to cells while removing waste products. The document describes the structure of the heart and the functions of its different chambers. It also explains the composition of blood, including red blood cells, white blood cells, platelets, and plasma. — URINARY SYSTEM Major Organs: Kidneys, ureters, urinary bladder, urethra. Remove waste from blood. Maintain water and electrolyte balance. Store and transport urine. The urinary system filters waste products from the blood, regulates fluid balance, and eliminates waste in the form of urine. The document illustrates the position and orientation of the urinary system organs. — MUSCULAR SYSTEM Major Organs: Muscles. Cause movement. Maintain posture. Produce body heat. The muscular system is responsible for movement, posture, and heat generation. The document classifies muscles into three types: skeletal, smooth, and cardiac. — LYMPHATIC SYSTEM Major Organs: Lymphatic vessels, lymph nodes, thymus, spleen. Return tissue fluid to blood. Carry certain absorbed food molecules. Defend the body against infection. The lymphatic system plays a crucial role in immune defense, fluid balance, and nutrient transport. The document describes the structure and function of lymph nodes and the spleen. — IMMUNE SYSTEM Parts of immune system : Bone Marrow: Produces white blood cells. Lymph Nodes: Filter harmful substances and activate immune responses. Spleen: Destroys malfunctioning and old cells. Types of immunities : Innate Immunity: Provides immediate, non-specific defense against pathogens. Adaptive Immunity: Highly specific, long-lasting protection that remembers past encounters with antigens. The immune system protects the body from disease by recognizing and destroying foreign invaders. The document explains the different components of the immune system, including white blood cells, lymph nodes, and the spleen. It also details the mechanisms of innate and adaptive immunity. — INTEGUMENTARY SYSTEM Major Organs: Skin, hair, nails, sweat glands, sebaceous glands. Protect tissues. Regulate body temperature. Support sensory receptors. The integumentary system is the body's largest organ, providing a protective barrier, regulating temperature, and enabling sensory perception. — NERVOUS SYSTEM Major Organs: Brain, spinal cord, nerves, sense organs. Detect changes. Receive and interpret sensory information. Stimulate muscles and glands. The nervous system controls and coordinates all bodily functions through the transmission of nerve signals. The document describes the structure and function of the central nervous system (CNS) and the peripheral nervous system (PNS). It also explains the different types of neurons and their roles in communication. — ENDOCRINE SYSTEM Major Organs: Pineal gland, hypothalamus, pituitary gland, thyroid, thymus, pancreas, adrenal glands, testes, ovaries. Regulate bodily functions through hormones. Coordination. Growth and development. Metabolism. Fluid balance. Reproductive process. Stress response. ——— LESSON 6 : EVOLUTION —— EARLY THEORIES OF EVOLUTION Jean Baptiste de Lamarck: Theory of Inheritance of Acquired Traits: Lamarck proposed that organisms can pass on physical characteristics acquired during their lifetime to their offspring. Theory of Use and Disuse: He believed that the more an organism uses a particular part of its body, the more developed it becomes, and vice versa. This theory is also known as Lamarckism. Vestigiality: The phenomenon of retaining genetically encoded physical structures that have lost their ancestral function in a given species. Examples: Appendix, wisdom teeth, tailbone. Hypertrophy: The process of using parts of an organism more, causing them to be retained and enlarge. Atrophy: The process of not using an organism's parts as much as their actual use, causing the part to degrade, deteriorate, and eventually be removed due to lack of use. —— CHARLES DARWIN'S THEORY OF EVOLUTION Natural Selection: The differential survival and reproduction of individuals based on their heritable traits. Organisms with traits better suited to their environment are more likely to survive and reproduce, passing on those traits to their offspring. Idea of Common Descent: All living organisms share a common ancestor. Idea of Gradualism: Evolution occurs gradually over long periods of time. Idea of Multiplication of Species: New species arise from existing species through the process of evolution. —— ARTIFICIAL SELECTION VS. NATURAL SELECTION Artificial Selection: The process of selecting and breeding animals and plants over many generations to achieve desired modifications by humans. Examples: Domesticated animals, crops. Natural Selection: The process where nature selects which organisms will survive and reproduce based on their traits. —— EVIDENCES OF EVOLUTION Fossil Records: Mineralized remains of living things over a long period of time. Comparative Anatomy: Homologous Structures: Similar structures with different functions. Example: The forelimbs of humans, cats, horses, bats, and dolphins. Analogous Structures: Similar structures with similar functions. Example: The wings of bats, birds, and butterflies. Comparative Embryology: Closely related organisms go through similar stages in their embryonic development. Comparative Biochemistry: Several species of organisms have similar biochemical pathways. Example: All mammals share almost the same biochemistry.  Molecular Biology: All living things are said to be basically alike. The fact that all living things have DNA and/or RNA affirms the evolutionary theory that all living things share a common ancestor. Biogeography: The continental drift theory explains the geographic distributions of similar or closely related organisms. ——— WEEK 7 : BIOTIC POTENTIAL AND ENVIRONMENTAL RESISTANCE ECOLOGY The study of living organisms and their interactions with each other and their environment. ECOSYSTEMS A biological community of interacting organisms and their physical environment. — ECOSYSTEM STABILITY Conditions for Ecosystem Stability: A constant supply of energy (the sun is the source for all life on Earth). Living organisms that convert energy into organic compounds (plants - autotrophs - photosynthesis). Recycling of materials between organisms and the environment. ABIOTIC FACTORS : Nonliving components that influence an organism (e.g., temperature, water availability, sunlight). BIOTIC FACTORS : Living components that interact with an organism (e.g., predators, prey, competitors). — POPULATION GROWTH - POPULATION GROWTH RATE : Dependent on biotic potential and environmental resistance. - BIOTIC POTENTIAL : Measures how well a species has adapted to survive (e.g., defense mechanisms, resistance to adverse conditions, migration, seed dispersion). - ENVIRONMENTAL RESISTANCE : Factors that limit population growth (e.g., disease, availability of food, predators). — POPULATION DYNAMICS - POPULATION : All individuals of a species that live in an area. - DEMOGRAPHY : The statistical study of populations, used to predict population changes. - POPULATION SIZE : The number of individuals in an area. Determined by the growth rate (births vs. deaths). - DENSITY : Measurement of population per unit area or volume. - DISPERSION : The spatial pattern of individuals in a population relative to one another. — FACTORS AFFECTING POPULATION DENSITY DENSITY-DEPENDENT REGULATION : Population growth rates are regulated by the density of a population. Most density-dependent factors are biological (biotic) in nature. Examples: Predation, inter- and intra-specific competition, accumulation of waste, diseases caused by parasites. DENSITY-INDEPENDENT REGULATION : Factors that are typically physical or chemical (abiotic) in nature that influence mortality regardless of population density. Examples: Weather, natural disasters (storms, forest fires, flooding, pollution). — TYPES OF BIOLOGICAL INTERACTIONS NEUTRALISM : Two populations interact, but neither affects the evolutionary fitness of the other. MUTUALISM : A mutually beneficial symbiotic relationship (both organisms benefit). COMMENSALISM : A one-sided symbiotic relationship (one organism benefits, the other is unaffected). AMENSALISM : One organism is inhibited or destroyed, the other is unaffected. PARASITISM : One organism (parasite) lives on or in another (host), causing harm. PARASITOIDISM : A form of parasitism where the parasitoid lives on or inside the host and eventually kills it. COMPETITION : Organisms compete for resources. PREDATION : One organism feeds on another. — BIOTIC POTENTIAL Definition: The ability of a population to grow under ideal environmental conditions. Factors Affecting Biotic Potential: Predation: Predators can significantly impact prey population growth. Presence of Diseases: Diseases can cause high mortality rates. Food Scarcity: Limited food resources lower reproductive capacity. Changes in Environmental Conditions: Climate change can impact reproductive success and survival. — CLASSIFICATION OF ORGANISMS BASED ON BIOTIC POTENTIAL Generalist: Organisms that can live in various habitats, have a wide diet, and are adaptable to changing conditions. Specialist: Organisms with specific resource needs, limited habitat preferences, and are more vulnerable to environmental changes. — HUMANS AS GENERALIST OR SPECIALISTS Humans are considered "generalist specialists". They can occupy and utilize diverse environments but also specialize in adapting to specific environmental extremes.