Genetic Engineering in Biology - ELS 2nd Quarter Review

REVIEWER IN ELS (2nd SEM – 2nd Quarter)  Bacteria, yeasts, and cultured plant and animal cells are usually used for recombinant DNA experiments. 7.3 PRODUC...

REVIEWER IN ELS (2nd SEM – 2nd Quarter)  Bacteria, yeasts, and cultured plant and animal cells are usually used for recombinant DNA experiments. 7.3 PRODUCING GENETICALLY MODIFIED ORGANISMS  Molecular cloning is done by cutting the desired DNA fragment (gene) into DEOXYRIBONUCLEIC ACID (DNA): The genetic material present in sex cells is used as a vector, usually either from a virus or a bacterial plasmid a carrier of genetic information passed on from parent to offspring through a genetic Vector in molecular cloning refers to a DNA molecule used as a vehicle to carry a material called deoxyribonucleic acid. foreign genetic material to another cell.  Every human body cell contains 23 pairs of chromosomes. A smalls plasmid from E. coli is a circular DNA containing about 1000 to 2000 base  Each cell in the human body contains about 35 000 genes. pairs that can replicate independently inside a bacterial cell.  Genes: A distinct portion of the DNA responsible for an inherited trait. These are coded instructions that must happen in the body, including how you function GENETICALLY MODIFIED PLANTS: advances in genetic engineering have been and how you look. particularly useful in medicine and in agriculture.  The genetic material found inside the nucleus (genotype) is expressed as an 1) Pest-Resistant Crops: a major effort seen in manipulating plant genes for observable characteristic (phenotype). agriculture has been involved in making crops resistant to insects and pests  Central dogma of molecular biology: flow of genetic information to protein. without the use of harmful chemicals. Replication: a process where a single-strand of DNA will serve as template to produce  Cotton fibers: widely used in the garments and textile industry, can hardly its complementary strand. survive insect attacks.  About 40% of chemical pesticides can kill insects that devour cotton plants. Transcription: a process, prior to the production of proteins, the messenger RNA  Bacillus thuringiensis (Bt) is a soul bacterium which produces crystal (mRNA) is first synthesized using the DNA as a template. proteins that is toxic to crop pests. Translation: a process where the mRNA is finally used as a template to produce the  Proteins are toxic to pests but not to humans. desired protein in the code of DNA found in the nucleus of the cell. 2) Herbicide-Resistant Crops: Agriculturists also encounter problems controlling weeds or unwanted plants that compare with crops for space, water, and Codons: mRNA bases form a three-letter base combination triplet. nutrients.  One codon corresponds to one amino acid (the basic building block of proteins).  Glyphosate: kills weed but it also stops the crops for growth. 3) Plants with More Nutritional Values: the production of genetically engineered GENETIC ENGINEERING: a technique that allows a specific gene from on organism to plants that will greatly benefit the customers. be transferred into the DNA of another organism.  Golden rice: notable projects that addresses the nutritional deficiencies associated with vitamin A.  Selective breeding: the process of using plants or animals with desirable traits o This has a yellow color because it contains beta-carotene. to reproduce offspring with specific traits.  Hybridization: the process of crossing plants or animals with different variations  About 250 million children suffer from vitamin A deficiency. of the same trait to create an organism with the best trait, has been around for  Iron and vitamin A deficiencies have been affecting third world countries many years as well. for many years. RECOMBINANT DNA TECHNOLOGY: It is the technique of combining two DNA GM FOOD CONSUMPTION AND POTENTIAL RISKS sequences from different sources. GM FOODS: they are criticized for their potential environmental hazard and probable  Its goal is cloning a particular gene for analysis or mass production of medically consequences of digesting them useful protein product. CONCERNS ON THE CONSUMPTION OF GM CROPS 1) They are potentially harmful to other organisms.  Omnivore: an organism that eats both flesh meat and plants.  Transgenic crop could be harmful to some insects. ANIMALS HAVE ADAPTIONS FOR ESCAPING PREDATORS 2) They can elicit resistance.  The exposure of weeds to the GM crops could lead to the growth of  Camouflage: have the abilities such as smelly sprays, stingers, and skin capable herbicide-resistant “superweeds,” which would require traditional toxic of blending (camouflage). pesticide. 3) They can affect the gene flow. ANIMALS REPRODUCE THROUGH SEXUAL AND ASEXUAL MEANS  The possibility of pollen transfer for interbreeding and producing new  Most animals reproduce by merging a tiny, mobile sperm cell and a much larger hybrids is another concern. female egg cell in the process of fertilization. GENETICALLY MODIFIED ANIMALS  Hydra: an unusual animal that lives exclusively in fresh water. 1) Transgenic Animals ANIMALS MOVE FROM PLACE TO PLACE  Gene pharming: uses transgenic animals to produce pharmaceuticals  Animal movement is a diverse characteristic among animals that is usually products for therapeutic and diagnostic purposes. related to obtaining food, finding a mate, reproducing its own kind. 2) Clones  Xenotrasplantation: another genetic engineering application or the use of 8.2 ANIMALS’ SPECIALIZED STRUCTURES animal organs instead of human organs in transplant patients. Cell grow, mature, and undergo differentiation in multicellular animals, resulting in 8.1 THE WORLD OF ANIMALS tissue formation. EARTH: the only planet that supports life and filled with diverse creatures as a result  The human body is made up of more than 200 differentiated cells. of over three billion years of evolution.  Histology: the study of animal and plant tissues.  Microtome: an instrument used to cut tissues into ultra-thin sections. ANIMALS: they are multicelled organisms that must obtain their food by eating other  Tissues sections are treated with biological stains (colors) to differentiate cells organisms. and tissues, and to have a clearer view of the different parts under the microscope.  Animal kingdom comprises an estimated 9 to 10 million species of animals on Earth, with at least four million currently named and identified. FOUR TYPES OF TISSUES FOUND IN ANIMALS  Most animals inhabit the seas, with fewer on freshwater, and even fewer on land. 1) Epithelial 2) Connective ANIMAL CELLS ARE ORGANIZED 3) Muscular 4) Nervous tissues  Animal cells are organized into specialized groups called tissues with distinct functions.  Tissues form an organ, which work together to perform a complex job.  The inner wall of the stomach has tall epithelial cells that help absorb food.  In most animals, different organs form organ systems. Smooth muscle surrounds the stomach and helps it move food through peristalsis. The stomach walls also have nerve tissues that send signals to the ANIMALS OBTAIN THEIR FOOD FROM OTHERS brain. Blood cells in connective tissue transport the absorbed food, and loose connective tissue connects the epithelial cells to other tissues in the stomach.  Herbivores: plant eating animals, such as grasshoppers, cows, snails, etc.  Tissues in the stomach have different roles but with a common goal: To digest  Carnivores: flesh eating animals, mostly predators—they hunt and kill preys such food. as lions, hyenas. 8.3 ANIMALS’ NEEDS FOR SURVIVAL  Chemical digestion – breaks down macromolecules (proteins, starch, and fats) into soluble molecules. THE NEED FOR PORTECTION AND SUPPORT 3) Absorption: The process where the digested food materials are taken by  An animal’s body is protected by an outer covering called integument. the cells and are converted into new protoplasm to provide energy.  Its main function is to cover and protect the organism. 4) Elimination: is the passing of materials that were not absorbed in the  Whiskers: special hairs of mammals that respond to touch. They grow on large intestine out of the body. the lips and cheeks of most mammals, but they also grow on other parts.  Feces: solid waste;  Roughage: undigested food; THEY NEED TO PROVIDE BODY SHAPE AND SUPPORT INTERNAL ORGANS  Anus: feces stored temporarily in the rectum before they are  Skeleton: a firm framework which gives physical support and protection excreted out of the body through an opening. for the body and provides surfaces for the attachment of muscles.  Defecation or egestion: the process of removing undigested matter  Hydrostatic skeleton: liquids in the bodies. from the body.  Exoskeleton: animals like corals, mollusks, crabs, and insects have a hard THE NEED TO TRANSPORT ESSENTIAL MATERIALS external covering.  Endoskeleton: higher forms of animals particularly vertebrates like Circulatory system: method of transport. fishes, frogs, chickens, and humans are supported by hard framework. TWO BASIC TYPES OF CIRCULATORY SYSTEM THE NEED TO MOVE  Open circulatory system – fluid is pumped through open-ended vessels  Skeletal muscles: are voluntary, which means you can control them and transported among the cells with no distinction between blood and consciously. interstitial fluid.  Smooth muscles: move food among the digestive system, while cardiac  Closed circulatory system – blood is confined within blood vessels muscle pump the heart and never stop working. separated from the interstitial fluid.  Antagonistic pairs: muscles in pairs that work against each other. THE NEED FOR A DFENSE SYSTEM  Extensor: muscles that causes to straighten.  Flexor: muscles that causes to bend.  Lymphatic system: sometimes referred to as the other circulatory THE NEED TO INDIGEST FOOD system.  Lymph nodes: tiny bean-like structures.  Nutrition: the food intake and the processes of food conversion.  These fluid do not return to the capillaries but collect in spaces around body cells in diffusion. FOOD PROCESSES IN ANIMALS  Lymph: leaked fluid. 1) Indigestion: intake of food into the body.  Lymphatic system is returned to the bloodstream through two 2) Digestion: the mechanical and chemical breakdown of food molecules veins located in the neck. into soluble and diffusible molecules that can be absorbed by body cells.  Infectants are present, lymphocytes (white blood cells) multiply TWO TYPES OF DIGESTION: rapidly to engulf and destroy them.  Physical digestion – mechanical breakdown of food by chewing and  Spleen: the largest organ in lymphatic system, lymphocytes are muscular contractions in the stomach. produced in here. DISEASE CAUSING AGENTS THE NEED TO CONTROL AND RESPOND TO ENVIRONMENTAL CHANGE 1) Viruses  Stimuli: nervous system keeps your body working properly despite the 2) Bacteria constant changes taking place around you. 3) Allergens  Nerve net: sea sponges lack a true nervous system but have a system of 4) Toxic chemicals separate but connected nerve cell.  Neurons carry information through the nervous system in the form of They causes abnormalities that disrupt the normal functioning or the body. nerve impulses. Immune response: coordinated process by the immune system at the THE NEED TO ELIMINATE WASTES AND OTHER HARMFUL SUBSTANCES introduction of a foreign substances.  Homeostasis: the process of maintenance if the internal environment of THE NEED TO RESPIRE AND EXCHANGE ESSENTIA GASSES the body.  Respiration: how the body gets oxygen and gets rid of carbon dioxide.  Without having to be conscious about your internal maintenance, the  Breathing: the act of taking in oxygen into the lungs and releasing carbon digestive, urinary, circulatory, and respiratory system work together so dioxide out of the lungs. that each cell receives the right amount of oxygen and nutrients.  Blood vessels: help transport oxygen-rich blood from the lungs to the MAJOR ORGANS SYSTEMS AND THEIR FUNCTIONS capillaries of body tissues and vice versa.  Integumentary exchange or cutaneous respiration: the use of entire skin  Integumentary: protects injury, infection. Provides structure and support. to exchange gases.  Muscular: moves limb and trunk through the body.  Mammals have lungs located inside the chest or thoracic cavity and  Skeletal: interacts with muscles for movements, protects and support. protected by the rib cage.  Circulatory: transport gases, nutrients, and wastes.  Circulatory system carries both oxygen and glucose to the cells where  Nervous: regulates behavior and other organ systems, controls sensory. respiration occurs.  Digestive: exacts and absorbs nutrients from food, remove wastes.  Respiratory: moves air in and out of lungs, controls gas exchange. THE NEED TO REGULATE AND MAINTAIN INTERNAL BODY PROCESSES  Excretory: removes waste from blood, regulates concentration of body  Nervous system: works by regulating most activities by sending nerve fluids. impulses throughout the body.  Endocrine: regulates body temperature, metabolism, development, etc.  Endocrine system: produces hormones that control many bodily  Reproductive: produces gametes and offspring. activities.  Immune: defend against pathogens and gases.  Hormones: made in the glands of endocrine system. 9.1 PLANTS HAVE ORGANS TOO  Endocrine glands: are ductless glands that secrete hormones directly into bloodstream or extracellular fluid. Charophytes is believed that modern land plants originated from ancestors  Positive feedback: this is when high levels of a hormone stimulate the related to green algae (phylum Chlorophyta in kingdom Protista). output of even more hormone.  Nonvascular plants: also known as byrophytes. They are mostly low-  Negative feedback: this is when mechanisms countertract hormone growing and do not possess true roots for absorbing water from the production. ground.  Tracheid: the conducting cells forming vascular tissues. THREE TYPES OF CELLS IN FUNDAMENTAL TISSUES:  Vascular plants: have true conducting tissues containing well-defined 1) Parenchyma cells: are large, thin-walled cells that contain plastids and tubes, which are suited for life in dry land and allow them to grow tall. usually have a large central vacuole. TWO TYPES OF TISSUES PRESENT IN VASCULAR PLANTS: 2) Collenchyma cells: are similar to parenchyma cells, except that they have  Phloem: brings manufactured foo from photosynthesis to other a thicker cell wall, hence, the function for support. plants.  Petiole or leaf stalk: reinforced with collenchyma cells.  Xylem: transports water and minerals from the soil. 3) Sclerenchyma cells: have thick secondary cells wall in addition to the PLANT TISSUES: Associated with the presence of vascular tissues is the primary cell wall. development of plant organs, which are specialized for essential plant  Lignin: an organic substance that strengthens the cell walls. functions.  Two types of sclerenchyma cells: o Fibers are long and slender;  Vegetative organs: organs that allow plants to live and grow. o Sclereids are irregularly shaped.  Other organs involved in reproduction are flowers, fruits, and seeds.  Meristems: tissues located in plant region where growth takes place. Vascular Tissues: are complex tissues conducting nutrients from roots to  Apical meristems: found at the tip of the stems or roots allow them to leaves. grow longer. TWO TYPES OF VASUCALR TISSUES  Lateral meristems: also called secondary meristems or lateral buds. This is found on the nodes of stems, are involved in the formation of branches.  Phloem: transport organic nutrients in both directions along the length  Cambium: ring of meristematic tissues found inside a mature stem, which of the plant. allows growth in diameter or increase in the thickness of stem or roots.  Xylem: transports water and minerals from roots to leaves.  Cork: new layers of surface tissue. TWO TYPES OF CONDUCTING CELLS FOUND IN THE XYLEM: Dermal Tissues: also called as surface tissues. It covers and protects the  Tracheids: are elongated, hollow nonliving cells with tapered ends. surface of the different plant organs.  Vessel element: are hallow and nonliving but are larger and devoid of end walls.  The outer cell wall of the epidermis is covered with a layer of cuticle,  The phloem contains living conducting cells called sieve tube cells, along which is made up of cutin. with a companion cell.  Cutin: is a waxy substance that prevents water loss.  Sieve plates: these are the end walls of the sieve tube.  Epidermis: found in the outer layer of green stems, roots, flowers, and  They are perforated, allowing cytoplasmic connections between seeds. vertically stacked cells.  Root hairs: slender projection found in the epidermal cells of roots that help modify a cell to increase the surface area of the root for absorption. PLANT ORGANS: plan tissues eventually form organ system.  Guard cells: modified epidermal cells found on leaves that open or close  All flowering plant have something in common. They all possess a root the stomata. system and a shoot system.  Stomata: leaf opening for gas exchange. Leaves: are the chief organ of plants for photosynthesis. Ground Tissues: also called fundamental tissues. This form the main bulk of plants. They fill most spaces in any plant organ. Stem: an above-ground structure that support the leaves, transport water  Primary xylem and primary phloem: produced by apical meristems. and important nutrients between roots and leaves, and produces new tissues Secondary growth: the widening or thickening of stems that occurs in lateral during growth. meristems.  Apical bud: terminal bud at the end of the stem that produces new leaves  Vascular cambium: a type of lateral meristem that produces secondary and tissues during primary growth. phloem and secondary xylem.  Axillary bud: branches that grows from the lateral bud where a leaf  Cork cambium: gives rise to the waterproof outer part of the bark of trees connects with the stem. and shrubs.  Internode: region in between nodes.  Stems can also be herbaceous or woody. Plant Responses: plants also respond to environmental change, such as  Herbaceous stems have no wood, they are soft. changing their direction of growth or move individual parts because of  Woody stems are hard and rigid as seen from trees. stimulus. Roots: this enables plant to anchor itself into the soil while absorbing water  Tropism: process of growth. and minerals (nitrogen, phosphorus, potassium, and etc.).  Positive tropism: growth toward stimulus.  Negative tropism: growth away from a stimulus.  Roots have a slimy surface and cylindrical shape, which allows the plants  Phototropism: the response when plants respond to a light source such to penetrate soil as they grow in size and allow water to be absorbed in as leaning toward the window to trap sunlight. all directions.  Heliotropism: a kind of tropism in response to the tracking of the sun.  Root cap: tip of the rood in shape covered with structure.  Gravitropism or geotropism: this is in which root tips grow downward  Root hairs: root tip bears which increase the absorptive capacity of roots (positive gravitropism), while plants shoots grow upward (negative and also help to anchor the plant. gravitropism).  Fibrous roots: they attach this to the grass’s soil.  Chemotropism: the plant’s reaction to chemicals.  Carrot’s taproots: stores the products of photosynthesis.  Thigmotropism: the response by plants to any contact stimuli.  Some roots are called adventitious roots that arise from an organ other  Makahiya plant is when it closes, it leaves upon physical contact. than roots such as the stem or a leaf.  Nastic movements: slight movements in response to any stimulus.  Prop roots: an adventitious roots can be modified for aerial support.  Thermotropism: the response of plants to the changes in temperature. 9.2 PLANT GROWTH AND RESPONSE Plants exhibit a circadian rhythm, a 24-hour cycle of processes, which include Plants depend on adaptive traits for their survival. closing and opening of the stomata, “sleeping movements,” or folding and unfolding of leaves and flowers. What gives a plant support to stand and reach for sunlight? The organ mainly responsible for giving the plant a steady support to its stem.  Photoperiodism: plants that respond to seasonal changes.  Open growth: growth pattern of plants. In phototropism, auxin is produced in the stem to stimulate plant elongation,  A plant adds new branches, leaves, and roots throughout its life. that is, it makes the plant grow taller. Primary growth: elongation of stems and roots that happens in apical HORMONES AND PLANTS RESPONSES meristems.  Gibberellin: promotes seed germination, growth of new leaves.  Cytokinin: delays aging.  Abscisic acid: inhibits growth, maintains dormancy, closes stomata during water stress.  Ethylene: promotes maturation, enhances fruit ripening.  Phytochrome (pigment): detects light, changes form in response to light.