Biology Reviewer PDF

BIOLOGY REVIEWER MODULE 1: The Theories About the Origin of Life Biology the study of living organisms such as plants, animals and microorganisms. Theory is widely accepted explanation of a biological phenomenon based on sound evidence from rigorous empirical experiments and scientific observation...

BIOLOGY REVIEWER MODULE 1: The Theories About the Origin of Life Biology the study of living organisms such as plants, animals and microorganisms. Theory is widely accepted explanation of a biological phenomenon based on sound evidence from rigorous empirical experiments and scientific observations. Six Major Theories that explain the origin of life on Earth: 1.) Divine Creation Theory - Religion/Christian Belief - proposes that life on Earth is created by a supernatural power, the God. - all living organisms were created on the same day. - they were created in the present form. - their bodies and organs are fully developed to meet the requirements to run life. 2.) Abiogenesis Theory - also known as Spontaneous Generation Theory by Alexander Oparin & J.B.S Haldane - assumes that non-living materials in a spontaneous manner gives rise to life. - observed that hair of a horse tail dipped in the water gives rise to a horsehair worm, Gordius. - fly larvae develop on rotten meat 3.) Biogenesis Theory - by Louis Pasteur - life can arise from pre-existing living things - this theory is mostly supported by scientists community. 3 scientists disprove the theory of spontaneous generation: Francesco Redi- In his experiment setup, 3Jars were used with meat inside uncovered, covered with gauze, and covered. Lazzaro Spallanzani- He boiled the broth in both bottles for long period at a high temperature. Louis Pasteur- used a swan neck flask in his experiment. 4.) Theory of Catastrophism - by Bishop James Ussher & Baron Georges Cuvier. - assumes that life originated by creation and is followed by catastrophe due to geographical disturbances. 5.) Theory of Cosmozoic - by Ritcher & Arrhenius - also known as Theory of Panspermia or Spore Theory  - assumes that life was present in the form of resistant spores and appeared on Earth from another planet. 6.) Theory of Eternity of Life - by Hermann Bondi, Thomas Gold, and Fred Hoyle. - also known as Steady State Theory - assumes that life has no beginning or end. Believes that life has always existed and will continue to be so. MODULE 2: The Level of Organization of Living Things Organism has a highly organized body system from smallest to the complex structure working together to perform specific function for an organism to live, adapt, reproduce, and survive. Level of Organization 1.) Atoms - smallest scale - fundamental unit of matter - when atoms combined it forms molecules 2.) Molecules - chemical structure consisting of at least 2 atoms held together by one or more chemical bonds. - DNA which contains the instructions for the structure and functioning of your body. 3.) Organelle - subunit of a cell and consist of functioning biomolecules - take part in the chemical reaction and interaction of cellular processes of an organism. 4.) Cells - building blocks of life. - classified as prokaryotic (single cell) and eukaryotic (multicellular) 5.) Tissue - group pf similar cells performing specific function within an organism. a. Animal Tissues: Epithelial, Muscle, and Nervous Tissues => Connective Tissues b. Plant Tissues: Vascular, Dermal, and Ground Tissues. 6.) Organ - collection of tissues group together performing “common functions”. => Vital Organs (animals)- Brain, Heart,Liver, Lungs, and Kidney  => Vital Organs (plants)- Leaves, Roots, and Stem 7.) Organ Systems - higher level of organization that consist of functionally related organs. 8.) Organisms - living individual entities which composed of various organ system that function altogether. 9.) Population - group of organism of the same species living together within a specific area. 10.) Community - group of organisms composed of different species which and interacting in a certain area. 11.) Ecosystem - group of organisms of having an interaction with non-living environment (air, nitrogen, soil, rainwater).  12.) Biosphere - global sum of all ecosystem and represents the zone of life on Earth. MODULE 3: The Definition of Cell Theory The Cell is the basic unit of life. The discovery of cell was made possibly by the development of the microscope in the 17th century. 1.) Zacchariastc Janssen & Hans Janssen- During 1590’s 2 Dutch spectacle makers, made the first compound microscope by combining two convex lenses inside a tube. 2.) Robert Hooke- In 1665, he studied thin slices of dead cork under a microscope. He discovered that cells are the basic unit of life. 3.) Anton Van Leeuwenhoek- The first man witnessed a live cell under a microscope. In 1674 he described the Algae Spirogyra and named the moving organisms animalcules “little animal”. 4.) Matthias Schleiden- In 1838, a German Botanist showed that the development of the vegetables tissues come from the activity of cells. 5.) Theodore Schwann- In 1839, he is a German Zoologist. The first use the term metabolism, he studied digestion in animals.  6.) Rudolph Virchow- In 1855, he developed the third and final part of the cell theory. He stated that all living things come from other living things. First witnessed a cell divided. MODULE 4: Introduction to Cell Structure and Functions of Animals and Plant Cells  Cells- the building blocks of life.  Organelles- a sub-cellular structure that has one or more specific jobs to perform in the cell. LIST OF ORGANELLES  Cell Walls- the covering of plant cell which is present only in plants. It is made up of cellulose. It protects the cell, provides structural support, and gives shape to the cell.  Plasma Membrane- it controls the passage of organic molecules, ions, water, and oxygen into and out of the cell.  Endoplasmic Reticulum- a series of interconnected membranous sacs and tubules within the cytoplasm that collectively modifies proteins and synthesizes lipids. 2 types of Endoplasmic Reticulum: a.) Rough Endoplasmic Reticulum- rough due to the ribosomes attached to the membrane ( protein synthesize). b.) Smooth Endoplasmic Reticulum- network of tubular sacs, without ribosomes in membrane (synthesize of Carbohydrates, Lipids and Steroid Hormones).  Cytoplasm- entire region of cell. It maintains shape to the cell, bear cell organelles and carry out different metabolic processes.  Ribosomes- it is a tiny dots that fat freely in the cytoplasm. For protein synthesis.  Golgi Body/Golgi Apparatus- named after Camillo Golgi. It function is to sort, tagging, packaging, and distribution of lipids and proteins destined to leave the cell.  Lysosomes- use hydrolytic enzyme to destroy pathogens that might enter the cell.  Peroxisomes- it detoxify many poisons that may enter the body.  Mitochondria- responsible for making adenosine triphosphate, main energy carrying molecules.  Chloroplast- a plant cell organelle that carry out photosynthesis.  Vacuoles- regulating the cell’s concentration of water in changing environmental conditions.  Cytoskeleton- help maintain the shape of the cell, secure some organelles in specific motion.  Nucleus- known as the governor of the cell. It controls all the activities of every organelle inside the cell. MODULE 5: Introduction to Cell Structures and Functions of a Bacterium. Bacteria are one of the most harmful microorganism that can cause diseases, specifically infections to many living things. – most names of bacteria came from their shapes. 1.) Cell Wall- bacteria cell wall composed of peptidoglycan.It helps in providing support, mechanical strength and rigidity to cell. 2.) Capsule- protective covering of bacteria made up of polysaccharide. It keeps the bacterium from dying out and protect it from phagocytosis by larger microorganisms. 3.) Cytoplasm- also called as store house of all the chemicals an components that are used to sustain the life of a bacteria. 4.) Plasma Membrane- a semi-permeable membrane which allows only selected materials to move inside and outside the cell. 5.) Ribosomes- helps in transferring the genetic material of bacterial cells.  6.) Flagella- hair like structure that helps the bacterial cell to move in clockwise and counterclockwise. 7.) Pili- small hair like projections. It assist the bacteria in attaching on a surface or sometimes to host. 8.) Plasmid- a small circular DNA, it exchanged DNA between bacterial cell. 9.) Nucleoid- the irregularly-shaped section of the prokaryotic cell where DNA is housed, it contains RNA, proteins and enzymes used for cellular processes. MODULE 7: The Difference Between Eukaryotic and Prokaryotic Cells  Prokaryotic Cells- organisms made of one cell that does not have a nucleus or other organelles covered by a membrane. 2 types os Prokaryotic Cells: Bacteria - most common prokaryotic. - no nucleus, no membrane bound organelle, DNA shaped like twisted rubber and has cell wall outside cell membrane. Archaea - singular archaean. - some live in places where no other organisms could live. - no nucleus, no membrane bound organelle, circular DNA, and has cell wall.  Eukaryotic Cells- the largest cells. It can have one cell or many cells. MODULE 8: The Various Cell Types of Animals (Animal Tissues) Tissues - a group of similar cells that perform specific function. - Unicellular organism consist of one cell as lower forms of organisms. - Multicellular organism is made up of several cells of various sizes, shapes and arrangements.  Epithelial Tissues- covers the body’s internal and external surfaces with one or more laters of tightly packed cells. It also covers the organ surfaces. 2 types of Epithelial: 1. Simple Epithelium- consist of singular layer of cells. 2. Stratified Epithelium- made of multiple cell layers.  Muscle Tissues- specialized cells that have a primary function of contraction. Muscles are classified according to: 1.) Location 2.) Appearance 1.) Striated- if cross striation are observed or unstriated. 2.) Smooth- if cross striation are not noticeable. 3.) Neutral Control 1.) Voluntary Muscles- found outside of the skeleton and are under control of the will. 2.) Involuntary Muscles- produced movements over which we have no control.  Connective Tissues- It bind together various parts of the body. To give form and support the body. 1. Loose of Areolar- loosely arranged fibre-elastic tissues. It holds together coagulable tissue fluids, various cells and all fibers. 2. Dense Connective Tissue- contains tightly packed collagen fibers, making it stronger than loose connecrive tissue. It founds in tendons and ligaments. 3. Adipose or Fats Tissue- function for the nutrients and fat storage. 4. Blood Tissue- classified as special connective tissue, because it is composed of cell and extra cellular matrix. a. Erythrocytes (Red blood cells)- responsible in transporting oxygen. b. Leukocytes (White blood cells)- responsible for immune system. c. Thrombocytes (Platelets)- plays a key role in blood clotting.   Nervous Tissues- receives and transmits stimuli in the form of nerve impulse to various effectors , such as muscles and glands. 1.) Neuron- made up of; Dendrite- carries the impulse towards the cell body. Axon- carries the impulse away from the cell body; usually long and unbranched. Myelin Sheath- a nucleated cell membrane covers the axon cylinder. 3.) Neuroglia- they support, nourish, and protect the neurons. MODULE 9: The Various Cell Types of Plants (Plant Tissues)  Botany a branch of science that deals with plants.  Botanist is the person who studied the plant structure and its functions.  Histology is the science that deals with tissues, and the person who studied is known as Histologist. 4 main types of plant tissue: 1.) Protective tissue- covers the surface of the leaves and the living cells of the roots and stems. Cells are flattened with their top and bottom surfaces parallel.  Epidermis - plant “skin”. - single layer of closely packed cells. - covers and protects the plant.  Periderm - also called as “bark” - replaces the epidermis in plants that undergo secondary growth. - consist of cork cells, protects the plant from pathogens. Cork cells- protects the plants from pathogens. It prevents excessive water loss, and provides insulation in plants. 2.) Meristematic tissue- tissues where cells are constantly dividing. This us the region that produce new cells. Generally small, six sided boxlike structures with a tiny vacuoles and large nucleus.  Apical Meristem  - can be near the tip of shoots and roots in plants. Primary Growth: increase in length (vertical growth). Also, produced embryo leaves & buds.  Lateral Meristem - secondary growth: increase in width (horizontal growth). => Vascular Cambium- thin, branching cylinder, responsible for the production of cell tissue that increases the thickness of plants. => Cork Cambium- thin, branching cylinder, responsible for the production of bark.  Intercalary Meristem - found in grasses and related plants that does not has vascular cambium and cork cambium. - actively producing new cells and responsible for the increase in length. 3.) Ground tissue- a “mechanical tissue”, synthesizing organic compounds, support the plants in providing storage.  Parenchyma - most abundant cell type. - spherical and flattened. - can divide if they mature and is vital in repairing damaged plant tissues. Parenchyma cells which may contains many chloroplast and form the tissues found in leaf are called CHLORENCHYMA => for photosynthesis. Aerenchyma tissues are cells loosely packed together with connected air spaces.  Collenchyma - found just beneath the epidermis. - generally elongated and walls are pliable. - provides flexible support for organs.  Sclerenchyma - have thick, rough secondary walls that are embedded with lignin. - at maturity, most are dead and function in structure and support. 4.) Vascular tissue- conducting tissues mainly for conducting water and nutrients.  Xylem- conducts water.  Phloem- conducts food and minerals. 5.) Specialized tissue- composed of two plant organs; STOMATA and TRICHOMES. a. Stomata- microscopic pore on the surface (epidermis) of plants. b. Trichomes- cutinized epidermal appendages found in the leaf, stem, flower, and fruit. It protects and prevent water evaporation. MODULE 10: MITOSIS-Introduction to Cell Cycle and Cellular Modification  Cytology a science that studied cells.  Cell division an integral part of the cell cycle. Cell divides to give rise to new ones, to replace those old and injured cells and to promote growth of organisms.   Cell cycle- orderly sequence of event that describes the stages of a cell’s life from the division of a single parent cell to the production of 2 new cells/daughter cells. Divided into 5 phases:  Interphase- a non dividing state. A period of growth and activity of the newly formed cell. The longest stage of the cell cycle and prepares the cell division. Four sub-stages: 1.) Gap 0 - cell will leave the cycle and quit dividing. 2.) Gap 1 - cell grows in size- organelles replicated. - cell undergoes intense growth. - cells of many organisms spend most of their lives in this phase. 3.) S Phase (DNA replication) - cells makes a precise copy of the DNA molecules in each of its chromosomes. - chromosomes are duplicated. - 2 identical copies remain together, joined by the centromere. Centromere- constricted region of a chromosomes and plays a key role in helping in the cell divide up its DNA during division. 4.) G2 Phase (preparation for mitosis) - the final stage. - cell continues to grow and begin a preparation for cell division. - synthesis of RNA and proteins occurs during this stage. 5.) Mitotic Phase - 2 copies of chromosomes are separated Mitosis is a process where a single cell divides into two identical daughter cells  6.) Cytokinesis - a process of the division of cytoplasm. - divides in half and become 2 new identical cells - also known as the final phase of cell cycle. MODULE 11: The Different Phases of Cell Cycle: Meiosis  Meiosis I is the reductional cell division, the chromosomes number is reduced by half (from 46 to 23 chromosomes)  Meiosis II is the equational cell division similar to mitosis which maintains the chromosomes number of organism (maintains 23 chromosomes) Meiosis I (process) 1. Prophase I- chromosomes have already duplicated. 5 stages of Prophase I  Leptonema- where duplicated chromosomes have coiled and are already visible.  Zygonema- the homologous begin to pair and twist each other in highly specific manner.  Synapsis- the pairing of homologous chromosomes and because the pair consist of four chromatids it is referred to as bivalent.   Pachynema- chromosomes become much shorter and thicker.  Crossing-over- a process of physical exchange of a chromosome region. The importance of crossing-over is to ensure genetic variability.  Diplonema- where two pairs of sister chromatids begins to separate from each other.  Chiasma- the area of contact between two non-sister chromatids.  Diakinesis- where the four chromatids of each tetrad are even more condensed. 2. Metaphase I- the centrioles are at opposite poles of the cell. Each pair of chromosomes attached with spindle fiber.  Metaphase plate- a plane equidistant from the poles. 3. Anaphase I- the two chromosomes of each bivalent (tetrad) separate and start moving toward opposite poles of the cells. 4. Telophase I- homologous chromosome pairs complete their migration to the two poles. 2 nuclei produced. Meiosis II (process) 1. Prophase II- there is formation of spindle apparatus. It involves the formation of sex cells. There is no synapsis and no crossing-over. 2. Metaphase II- chromosomes lined up at the center held by spindle fiber.  Kinetochore- a protein structure that forms on a chromatid during cell division and allows it to attach to a spindle fiber on the chromosomes. 3. Anaphase II- the centromere separates, and the two chromatids of each chromosome move to opposite poles on the spindle. 4. Telophase II- each daughter cell separates into 2, forming 4 daughter cells. A nuclear envelope forms around each set of chromosomes. Cytokinesis is the division of cytoplasm in cells.