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Bio Study Guide Units 1-5 Introduction: This study guide is to aid you in your final days towards the exam. DO NOT use this as your only source of studying because I will be asking you to reference the textbook. Reading is necessary to memorization and studying, as well as putting in solid hours of focus. You should not rely solely on our session to memorize material. Here are a few tips to help in your memorization process: #1. Focus section by section and make themes. Don't overwhelm yourself with three pages. Break information down into categories and systems. For example, when you are choosing areas to memorize, don't try to remember the function of every organelle separately. Look at a system, such as the Endomembrane System. Study how it works, the main functions it takes care of. This should form a better overall picture of what is going on so that each organelle make sense. #2. Don't worry about how much you have to memorize, focus on the present moment. Sometimes when we are studying we begin thinking about how much other information we have to memorize and this overwhelms our brain, and stresses us out! It impacts our ability to focus and memorize because we are not totally present. Being present means looking at and appreciating the material right in front of our eyes. Every time you feel yourself feeling panicky about how much you have to learn, bring yourself back to the word you are reading. #3. Have fun! I know this is the last thing you feel while studying, however if you think about it, biology is everywhere around us - and WE are biology! If you apply the information you are memorizing to the real world, and yourself, it will be easier to remember, and not such a drag.

Unit 1: ◊ The Process of Science - Two kinds of reasoning: inductive reasoning [drawing conclusions from collected & analyzed observations, also called, data.] and deductive reasoning [taking a general hypotheses and testing them in the hopes of generating specific data]. *Memorizing tip: inductive = specific data → general conclusions deductive = general conclusions → specific data - A hypothesis must be testable & falsifiable: meaning there must be some way to check it's viability (how true it is), as well as a way to prove it incorrect (it's falsifiability). - Describe what is involved in a controlled experiment (an experiment that compares an experimental group to a control group). Ideally both groups only different by one factor. Without the control group, scientists wouldn't be able to rule out other variables, such as environment. (e.g. if one group in the experiment sits in an extremely cold room, this may impact results if you are testing mood, test-taking, social interactions, etc. In this case, a scientist would make sure conditions were exactly the same in both the experimental and control group except for ONE factor, the factor being tested).

◊ Bonds & Water - Table salt (NaCl) is an example of how the transfer of electrons can bond atoms together. Sodium (Na) has only 1 electron in its outer shells, whereas chlorine has 7. When these atoms interact, the sodium atom donates its single outer electron to chlorine. Electrons are negatively charged particles. The transfer of an electron between the two atoms moves one unit of negative charge from one atom to the other. - An ion is an atom/molecule with an electrical charge resulting from a gain or loss of one or more electrons. Two ions with opposite charges attract each other. When the attraction holds them together, it is called an ionic bond. NaCl (sodium chloride) is electrically neutral together. -The environment affects the strength of ionic bonds. For example the ionic bonds of salt (NaCl) dissolves when interacting with water molecules (dropping salt in warm water, and your salt melts) ◊ The Chemistry of Life - an acid is a compound that denotes hydrogen ions to solutions - a base is a compound that accepts hydrogen ions and removes them from solution - we use the pH scale to describe how acidic or basic a solution is. Pure water and aqueous solutions that are neither acidic nor basic are said to be neutral (they have a pH of 7 on a scale where 0 is the most acidic and 14 the most basic). - The carbohydrate monomers (single-unit of sugar) are called monosaccharides (most common are glucose and fructose, found in fruit, sugary drinks, desserts) - Lipids are diverse compounds that are grouped together because they share one trait: they don't mix well with water. Lipids consist mainly of carbon and hydrogen atoms. Lipids are hydrophobic (water-fearing). A fat is a large lipid made of two kinds of smaller molecules: glycerol and fatty acids. -Phospholipids are the major component of cell membranes. Structurally they are similar to fats but they contain only 2 fatty acids attached to glycerol (as oppose to 3). It has hydrophilic (water-loving) and hydrophobic (water-fearing) ends of molecules that assemble in a bilayer (2 layers) of phospholipids to form the membrane. -Amino acids are the smaller units of proteins, they have an amino group and a carboxyl group (which makes it an acid). A protein's specific shape determines its function (structural, defensive, signal, receptor, transport, storage) - Genes are: a discrete unit of inheritance that program an amino acid sequence of a polypeptide. Genes consist of DNA (deoxyribonucleic acid), one of the two types of polymers called nucleic acids. DNA provides directions for its own replication. Thus, as the cell divides, its genetic instructions are passed to each daughter cell. These instructions program all of a cell's activities by directing the synthesis of proteins. The second type of nucleic acid is RNA (ribonucleic acid) is what builds the proteins directly and works as a translator between the genetic instructions and the protein-building machinery. ◊ An introduction to the Cell - a light microscope (LM) allows visible light to pass through the specimen under study (microorganism or a thin slice of animal/plant tissue) and then through glass lenses. The lenses bend the light in such a way that the image of the specimen is magnified as it is projected into your eye.

- an electron microscope (EM) focuses a beam of electrons through a specimen or onto its surface. Electron microscopes can distinguish biological structures as small as about 2 nanometres (much more detailed than a light microscope). Can explore a cells ultrastructure (the complex internal anatomy of a cell) - the scanning electron microscope (SEM) studies the detailed architecture of cell surfaces. Uses an electron beam to scan the surface of the cell and excites surface electrons and these electrons are then detected by a device that translates their pattern into an image projected onto a video screen - the transmission electron microscope (TEM) is used to study the details of internal cell structure. Aiming an electron beam through a very thin stained section of the specimen. It uses electromagnets as lenses (rather than glass) - The Cell Theory states: all living things are composed of cells and that all cells come from other cells - Suface-to-Volume Ratio: Large cells have more surface area than small cells, BUT they have less surface area relative to their volume than small cells. Because volume has depth (3D) and surface area doesn't, when a cell grows larger it's volume increases at a much faster rate than its surface area. - Prokaryotic cells: bacteria and archaea; structurally much simpler than eukaryotics; their DNA is not enclosed by a membrane; some have flagella (long projections that propel the cell through its liquid environment) - Eukaryotic cells: animals/plants/fungi/protists; structurally more complex; membrane-enclosed nucleus & DNA; tend to be larger than prokaryotic cells - cellular metabolism are chemical activities of cells that occur within organelles: nucleus, nuclear envelope, nucleolus, ER (smooth/rough), golgi apparatus, mitochondria, lysosomes, peroxisomes, ribosomes, chloroplasts, plasma membrane, etc. *Know the structure & function of each organelle - The endomembrane system includes: the nuclear envelope, endoplasmic reticulum, golgi apparatus, lysosomes, vaculoes and the plasma membrane - Endosymbiont theory states that mitochondria and chloroplasts were formally small prokaryotes that began living within larger cells. These small prokaryotes may have gained entry to the larger cell as undigested prey or internal parasites. This symbiosis could have become beneficial in a world that was becoming increasingly aerobic from the oxygen-generating photosynthesis or prokaryotes, a host would have benefited from an endosymbiont that was able to use oxygen to release large amounts of energy from organic molecules by cellular respiration. And a host cell could derive nourishment from a photosynthetic endosymbiont. Over time, the host and endosymbionts would have become increasingly interdependent, eventually becoming a single organism. ◊ Transportation - Osmosis: the movement of water from an area of low concentration to an area of higher concentration - Diffusion is the tendency for particles of any kind to spread out evenly in an available space. It moves via a concentration gradient, which states that there will be net movement from a place of lower concentration to a place of higher concentration - Passive transport (uses the concentration gradient) vs Active transport (uses ATP, energy) *Know the difference

-Facilitated diffusion is different in that it needs the help of specific transport proteins to carry the substance across the cell membrane. It is a type of passive transport because it does not require energy. As in all passive transport, the driving force is the concentration gradient. - A cell in a hypertonic solution will shrink; a cell in a hypotonic solution will expand; a cell in an isotonic solution will remain the same. - Exocytosis (exporting bulky materials like proteins) vs Endocytosis (taking in large molecules in various ways such as phagocytosis, pinocytosis & receptor-mediated endocytosis) ◊ Aerobic (using oxygen) Harvesting of Energy - Photosynthesis & Cellular Respiration (chloroplasts & mitochondria functions) *Know the basic processes of both - Photosynthesis converts CO2 and H2O into their own organic molecules and release O2 as a by-product - A plant's green colour comes from chlorophyll, a light-absorbing pigment in the chloroplasts that plays a central role in converting solar energy to chemical energy - Be ready to discuss the global climate change and the greenhouse effect that is exacerbated by human civilisation.(specifically greenhouse gases) - global warming

Terms to memorize for Unit 1: hypothesis, theory, inductive/deductive reasoning, controlled experiment, acid, base, phospholipid, lipid, carbohydrate, protein, nucleic acid, prokaryotic/eukaryotic cells, DNA/RNA, cellular metabolism, genes, cell organelles (all of them), microfilaments, microtubules, intermediate filaments, diffusion, active/passive transport, concentration gradient, hypertonic/hypotonic/isotonic, osmosis, exocytosis, endocytosis (all the types), photosynthesis, cellular respiration (and the organelles involved)

Unit II: ◊ Cell Division - Prokaryotes reproduce by binary fission (which means "dividing in half") and is an asexual form of reproduction because the genetically identical offspring inherit their DNA from a single parent - Eukaryotic cell cycle & Mitosis: as a cell prepares to divide, its chromatin coils up, forming tight, distinct chromosomes that are visible under a light microscope. The narrow tight "waist" where two sister chromatids are joined together is called the centromere. When the cell divides the sister chromatids of a duplicated chromosome separate from each other. Once separated from its sister, each chromatid is called a chromosome and it is identical to the chromosome the cell started with. One of the new chromosomes goes to one daughter cell, and the other goes to the other daughter cell. In this way, each daughter cell receives a complete and identical set of chromosomes. In humans, for example, a typical dividing cell has 46 duplicated chromosomes ?(92 chromatids) and each of the two daughter cells that results from it has 46 single chromosomes. - the cell cycle is an ordered sequence of events that extends from the time a cell is first formed from a dividing parent cell until its own division into two cells. The cell

cycle consists of two main stages: a growing state called Interphase (during which the cell roughly doubles everything in its cytoplasm and precisely replicates its chromosomal DNA, and the actual cell division called Mitotic phase. *Look at the diagrams in the textbook carefully pg. 129-131 - Meiosis is a type of cell division that produces haploid gametes (egg & sperm cells) in diploid organisms (most animals and many plants). There are two consecutive cell divisions: meiosis I & meiosis II consisting of prophase, metaphase & anaphase, telophase and cytokenesis - Homologous chromosomes are two matching chromosomal pairs that both carry genes controlling the same inherited characteristics. For example, if a gene that determines whether a person has freckles is located at a particular place (or locus) on one chroosome, then the homologous chromosome has the same gene at the same locus. ◊ Patterns of Inheritance - Heredity is the transmission of traits from one generation to the next. A character is a heritable feature that varies among individuals (e.g. flower color), and a trait is a variant of the character (e.g. purple vs white flowers) - Mendel's Laws: the law of segregation [a sperm or egg carries only one allele for each inherited character because allele pairs separate from each other during the production of gametes]. the law of independent assortment [the inheritance of one character has no effect on the inheritance of another. During gamete formation each pair of alleles assorts independently of other pairs of alleles. - Inbreeding: matings between close blood relatives usually caused by geographic isolation - A single gene may affect many phenotypes (observable characteristics), however a single character can be influenced by many genes (called polygenic inheritance). The environment can affect these characters such as: nutrition, health, climate. There is an old and hotly contested debate around whether human characters are more influenced by genes or by the environment (nature or nurture). The individual features of any organism arise from a combination of genetic and environmental factors. However, only genetic influences are inherited. Any effects of the environment are generally not passed on to the next generation. - The chromosome theory of inheritance states that genes occupy specific loci (locations) on chromosomes, and it is the chromosomes that undergo segregation and independent assortment during meiosis. Thus, it is the behaviour of the chromosomes during meiosis and fertilization that accounts for inheritance patterns. ◊ DNA Replication - Two main stages: transcription (the synthesis of RNA under the direction of DNA) & translation (the synthesis of protein under the direction of RNA). - The one gene-one enzyme hypothesis: the idea that the function of a gene is to dictate the production of a specific enzyme. There have been modifications though: now the hypothesis includes not the enzymes but all types of proteins. Now the hypothesis states: the function of a gene is to dictate the production of a polypeptide (a long chain of amino acids). This area continues to be researched! - mRNA (messenger RNA) encodes amino acid sequences by conveying genetic messages from DNA to the translation machinery of the cell. This information is then translated into polypeptides. tRNA (transfer RNA) works as an interpreter by converting

the words of nucleic acids to the amino acid words of proteins. Ribosomes then position mRNA & tRNA close together and catalyze the synthesis of polypeptides. ◊ Mutations - Any change in the nucleotide sequence of DNA is called a mutation - Two general categories: nucleotide substitutions (silent, missense and nonsense) and nucleotide insertions/deletions. *Know these definitions pg 199 - Insertion/deletions often have disastrous effects compared to substitutions (although the nonsense mutation can still be harmful) ◊Viruses and Bacteria - A virus is nothing more than "genes in a box": an infectious particle consisting of a bit of nucleic acid wrapped in a protein coat called a capsid, and in some cases, a membrane envelope. Viruses are parasites that can replicate (reproduce) only inside cells. In fact, the host cell provides most of the components necessary for replicating, transcribing, and translating the viral nucleic acid. - The replication cycle is called a lytic cycle because it results in the lysis (breaking open) of the host cell and the release of the viruses that were produced within the cell. Other phages (viruses) can also replicate by an alternative route called the lysogenic cycle, a viral DNA replication without destruction of the host cell. *Look at these cycles in detail pg 200 - Viruses can causes diseases in both animals and plants. Emerging viruses threaten human health such as HIV (AIDS), H1N1 flu (in 2009), SARS (in 2002). Look at the AIDS virus in particular (pg. 203 10.20). -Bacteria can transfer DNA in 3 ways: transformation, the uptake of foreign DNA from the surrounding environment. Transduction, the transfer of bacterial genes by a phage. And Conjugation, when two bacterial cells "mate" at the DNA level and transfer DNA (a physical union of two bacterial cells of the same/different species). ◊ Cloning - A clone: an organism who is produced through asexual reproduction from a single parent. Plant cloning is now used extensively in agriculture. Cloning has been used to reproduce a plant with desirable traits, such as high fruit yield (more fruit) or the ability to resist a plant pathogen (virus, parasite) - *Read about cancer pg 227 - Gene cloning; biotechnology; DNA technology: modern fields, manipulation of organisms to make useful products, studying/manipulating genetic material, modifying specific genes. - Recombinant DNA is formed when scientists combine nucleotide sequences (pieces of DNA) from two different sources to form a single DNA molecule. It is used in the field of genetic engineering. - To manipulate genes in the laboratory, biologists often use bacterial plasmids, which are small, circular DNA molecules that replicate (duplicate) separately from the much larger bacterial chromosome. Why? Plasmids can carry virtually any gene and are passed from one generation of bacteria to the next, they are the key tools for gene cloning, the production of multiple identical copies of a gene-carrying piece of DNA. - To become the recombination, biologists isolates two kinds of DNA: a bacterial plasmid (that serves as a the vector, or gene carrier) and the DNA containing the gene of interest. *Look at this process in detail pg. 232-233

- enzymes are used to "cut-and-paste" the DNA - DNA technology has changed the world in many ways: the pharmaceutical industry, diagnosing diseases, food & agriculture, DNA profiling in forensic cases *Choose one of these areas and explore how DNA technology has made an impact (I think you chose the forensic DNA profiling pg 242 and 245) Terms to memorize for Unit II: binary fission, mitosis, meiosis, chromosome, centromere, chromatid, haploid, diploid, gametes, fertilization, zygote, homologous , chromosomes, heredity, genetics, Mendel's laws, inbreeding, cross-fertilisation, hybrid, polygenic inheritance, the chromosome theory of inheritance, one gene-one polypeptide hypothesis, mRNA, tRNA, mutations, virus, transformation, transduction, conjugation, cloning, recombinant DNA, plasmids, gene cloning, vector, DNA technology, enzymes

Unit III: ◊ Darwin's Theory of Evolution - Charles Darwin's theory of evolution is the idea that Earth's many species are descendants of ancestral species that were different from those living today. He travelled to the Galapagos Islands in South America to do research and he observed many unusual organisms, most of which were not known from anywhere else in the world. - Darwin explained ho...