Exam I
I. Science Skills
9 Process Skills: Observing – using senses (see, hear, taste, smell, touch) Communicating – give or receive information Measuring – compare something to standard or non-standard units Classifying – use observations to group objects or events according to similarities and differences Interring – using past experiences to draw conclusions and make explanations about events not directly observed Defining Operationally – using past experiences to draw conclusions and make explanations about events not directly observed Predicting – a forecast about what will happen in the future ex: rainy days/ weather predictions Making Models – develop a physical or conceptual representation to explain an idea, object, event ex: atom, DNA, volcano Investigating – state the question, hypothesize, design investigation, collect data, report data, compare results, come to conclusion, 3 types depend on grade level and what problem they are trying to solve Scientific Investigations
Descriptive investigation – students describes or records what is observed Qualitative – word descriptions do not involve numbers Quantitative – measurements or amounts Experimental investigation – student changes or manipulates a variable and observes the corresponding change in another variable. Includes statement of variables (independent/dependent) the control, and the constants; ex: does the temperature of water affect the amount of sugar that dissolves? Comparative investigation – student describes and compares two similar natural occurrences; the occurrences would differ in one manner such as time or locations; ex: is there a difference in the amount of sediments between the head and the mouth ofo the river? Manipulated variable – a variable that is deliberately changed in an experiment. Only 1 can be tested; ex: amount of fertilizer used on plants Responding variable – a factor that changes as a result of changing the manipulated variable ex: result of the fertilizer / result o the manipulated variable Constant – all of the things that are kept the same ex: same size pot, amount of soil, light source, amount of water Control – the part of the experiment that doesn’t receive the manipulated variable. Used for comparison ex: plant without fertilizer Data Table – MV/left, RV/right Graph – MV/X, RV/Y
II. Chapter 1. Introduction to Biology
Biology – study of life Science – organized way to learn about the natural world Nature – everything that is not man-made Scientific Theory – large body of information, well tested and well verified hypothesis Law – describes an important relationship that occurs consistently overtime; a law is to describe what happens ex: mendel’s law of genetics, newton’s law of motion Hypothesis – possible answer to the question, based on evidence that can be tested (if, then)
8 Characteristics of life 1. Living things are composed of cells (one-celled organisms) ex: bacteria multi-celled organisms ex: animals & trees
2. Living things reproduce (reproduction definition: organisms that make more of own kind sexual reproduction: offspring are mixture of traits asexual reproduction: identical to parent) 3. Living things are based on universal genetic code (our inherited traits are carried by molecules of DNA, heredity)
4. Living things grow and develop (growth: increase in number and size of cells development: process in which the first cells of a new individual becomes an adult)
5. Living things obtain and use materials and energy (every organism takes in energy, converts it to useful forms and released energy)
6. Living things respond to their environment (ex: leaves and stems of plant growth toward light, trees lose their leaves)
7. Living things maintain a stable internal environment (homeostasis ex: bird and mammals have constant body temp, cells maintain constant water balance)
8. Taken as a group, living things change over time (individuals with traits that help them survive and reproduce pass those traits to offspring) ex: organisms that live in the desert survive because they adapt to conditions (cactus) Heredity – passing of traits from parent to offspring Homeostasis –process in which an organism keeps its internal conditions stable Evolution – the change in organisms over time
III. Chapter 2. The Chemistry of Life Matter – anything that occupies space & has mass (solid, liquid, gas)
Element – substance that cannot be broken down into simpler substances by chemical reaction (118 total elements, 90 naturally occurring) ex: carbon, oxygen, hydrogen, nitrogen make up 96% of living Compound – substance with 2 or more elements chemically combine in an exact ratio. Can be broken down by a chemical reaction ex: NaCl, H2O, C6H12O6 table salt, water, glucose Mixture – type of matter with a variable ratio of its parts, two or more substances are physically mixed by not chemically combines, parts of a mixture can be physically separated iron & salt, salt sand iron Physical Change – change in which does not alter the identity of matter; recognize: change in size or shape, change in state, color stays same, dissolving make a mixture ex: ice melts, sugar and water, salt and water, salt and pepper Chemical Change – change which alters the identity of matter; recognize: produce a gas, form a precipitate from 2 liquids, change color or odor or both, energy absorbed or released ex: burn, charge phone, cooking, digestion, iron rusts Atom – smallest part of an element that still has properties size one hundred million Atomic Number – # of protons in the nucleus; determines an atom’s chemical identity APE AM=P=E Mass Number – the total of the protons & neutrons in the nucleus MAN P+N=Mass Number; Mass number – atomic number = neutrons
Valence Electron – an electron of an atom, located in the outermost shell (valence shell) of the atom, that can be transferred to or shared with another atom (look at periodic table of elements) Isotope – forms of an atom that vary in the # of neutrons
COMPARE & CONTRAST ISOTOPES – Same: e-, p+, same properties, atomic number Different: n0, mass number
Three subatomic particles: proton p+ 1 amu nucleus, neutron n0 0 1 amu nucleus, electron e- 0.0005amu shell surrounding the nucleus The number of protons determines – the identity The number of electrons determines – how it reacts The number of neutrons determines – the isotope and mass number Chemical Bonds – force that holds atoms together to form a compound Why do atoms form bonds? Fill the valence shell, to become stable, to reach a state of lower potential energy
Ionic Bond – bond formed by the transfer of electrons which results in the attraction between charged ions
Covalent Bond – bond formed between two atoms sharing electrons What kind of atoms form ionic bonds? Metal and nonmetal What kind of atoms form covalent bonds? Hydrogen and nonmetal, nonmetal and nonmetal Nonpolar bonds – equal sharing of electrons, no difference in charge, no poles, do not dissolve in water
Polar covalent bonds – unequal sharing of electrons, properties, one atom pulls electrons to its end of molecule, results in slight positive and slight negative poles, dissolves in water Hydrogen Bond – attraction is between two different molecules, a hydrogen bond forms between hydrogen of one molecule and either nitrogen or oxygen of another molecule; ex: water; importance: causes the properties of water, shaped to protein & DNA
Water – importance: many organisms live in water, our cells are mostly water, our cell reactions require water, things that give you energy, DRAW STRUCTURE OF WATER, properties of water: when water freezes, forms a 6 sided crystal, ice expands when freezes, less dense than liquid water so ice floats, water helps regulate temperature; absorb and store heat energy without an increase in temperature, oceans help to moderate earth’s temperature, sweating helps moderate body temperature, water molecules attract strongly; cohesion, adhesion, capillary action, water has high surface tension, water dissolves many substances, hydrophilic, hydrophobic Adhesion – attraction between molecules between different substances Cohesion – attraction between molecules and the same
Capillary action – rise of a liquid in a small diameter tube (water can rise up a plant stem) Hydrophilic – water loving Hydrophobic – water fearing Solution – this is the homogenous mixture of two or more substances Solvent – part doing the dissolving usually the larger amount Solute – part being dissolved usually smaller amount
Examples of solutions in living things: human blood plasma (liquid glucose and gases dissolved in water) plant tissues (sugars dissolved in water) pH – power of hydrogen, measurement used to indicate how basic or acid a solution is 0-14 acidic, neutral, basic pH 8 and pH 10 10^2 10*10=100 pH 10 is 100 times more basic than pH 8. Acids – a chemical that when dissolved in water produces hydrogen ions h+ ph is below 7. Cola, wine, beer
Bases – a chemical that when dissolved in water accepts hydrogen ions pH is above 7, baking soda, bleach
Buffer – a set of chemical that keep pH stable, can neutralize only so many ions, excess acids or bases overcome buffer system, can cause damage to environment or to human cells.
IV. Biological Molecules Why is life carbon-based:
Carbon can bond with almost all the elements (not noble), carbon can form single, double or triple bonds with other carbons, carbon can form a long chain, a closed ring or a branched structure Three elements found in the biological molecules; carbon, hydrogen, oxygen. Monomer – small molecule (glucose)Polymer –large molecule made of many small molecules (starch) Dehydration synthesis reaction – building or making a polymer Monomer + monomer → polymer + h2o
Glucose + glucose → maltose + water Hydrolysis reaction – when polymer breaks down to monomer Polymer + h2o → monomer + monomer
Starch + water → glucose, glucose, glucose, etc Carbohydrates – importance: main energy source for all living things, structural material for all plants algae and some animals Monosaccharides – simple sugars ex: glucose, fructose, galactose Disaccharides – double sugars ex: sucrose, maltose, lactose
Starch – energy storage in plans coil structure Cellulose – long straight chains cross links to strength chain algae and plans
Glycogen – branched structure Chitin – structured material some animals and fungus straight chain cross linkage Polysaccharides – all are polymers made of many glucose molecules Lipids – fats, oils, waxes, steroids, phospholipids; properties of lipids contain the elements carbon, hydrogen, oxygen, all are hydrophobic
Importance of lipids – long term energy storage, insulation helps maintain body temperature, cushion internal organs, waterproof covering, helps prevent water loss
Phospholipids – important in structure of cell membrane; phosphate – hydrophilic Cholesterol – part of the structure of cell membrane, manufacture other steroids ex: vitamin d
Good & Bad Cholesterol – LDL low density for bad “lousy” waxy material builds up inside arteries, good HDL high density lipid goes in and removes LDL cleans up arteries structure of cell membrane “happy” Steroid hormones – estrogen, testosterone Prescription steroids – cortisone, prednisone
Anabolic steroids – build muscle Triglyceride – fats and oils consists of glycerol (three carbon alcohol), three fatty acid tails
Saturated fats – less healthy, contain single bonds between carbon atoms, fatty acid tails are straight, most are solids at room temperature, dietary source (mostly animal products) Unsaturated fats – more healthy; contain one more more double bonds between carbon atoms, fatty acid tails are bent or twisted, most are liquid at room temperature, dietary source (mostly plant oils) Trans fats – we don’t have the ability to digest them or hydrogenated oils, added because they make food stay fresh longer Protein – transport or move other molecules, defense, destroy foreign invaders, structure, movement, enzymes, speed up chemical reactions, protein hormones are chemical messengers Monomer unit – amino acids Importance of protein shape: the shape determines its function, change the amino acid change the protein Primary protein structure: sequence of a chain of amino acids Secondary protein structure: occurs when the sequence of amino acids are linked by hydrogen bonds Tertiary protein structure: occurs when certain attractions are present between alpha helices and pleated sheets
What happens if the protein loses its shape: if the shape changes, the protein becomes “denatured” and loses its function
What factors can cause a protein to lose its shape: change in pH (adding lime juice to apples), hair chemicals (hairspray) change temperature (cooking or fever)
Nucleic acids: monomer unit: nucleotide Importance of nucleic acids: ATP: cells for energy, DNA – store hereditary information RNA – messenger between DNA + rest of the cell V. Chapter 3. The Cell Cell – smallest structural unit that has the properties of life
Cell Theory – every living organism consists of one or more cells, all cells come from pre-existing cells, cells contain hereditary material that they pass on to their offspring Why are cells so small? Materials pass through the plasma membrane, the exchange of materials through the plasma membrane is more efficient with the small cell The rate at which materials pass through the plasma membrane depends on the SURFACE AREA of the cell The rate at which food and oxygen are consumed wastes formed depends on the VOLUME of the cell Prokaryotic cells – cells whose DNA is not enclosed in a nucleus ex: bacteria, archaea Eukaryotic cells – DNA is enclosed in a nucleus ex: plants animals fungi, algae, protozoa Two groups of Prokaryotes – domain bacteria, domain archaea Capsule – sticky outer coat helps cells stick to surfaces Cell wall – ridged outer layer protects cells & gives shape to the cell Plasma membrane – real thin layer regulate what enters and leaves the cell
3 Shapes all prokaryotes have – round, oblong; rod, spiral Eukaryotic cell structure: plasma membrane – thin flexible double layer membrane, regulate what enters and leaves cell, all cell have this; cell wall – big ridged outer layer, protect the plant, protect the cell, helps cell keep shape, provides support for plants, plants algae, fungi; nucleus – DNA is enclosed by the membrane, contains the cells of DNA, controls the cell’s activities; nuclear envelope – outer covering of the nucleus; nucleolus – big ball like produces RNA and ribosomes; chromatin – long fibers of DNA; nuclear pores – openings in nuclear envelope; ribosomes – some are attached some are free floating, RNA attaches to ribosomes, amino acids are joined to make protein; Rough ER – covered with ribosomes long chains of amino acids are folded into the correct protein shape; smooth ER – no ribosomes makes steroids lipids and hormones detoxifies drugs and alcohol; Golgi apparatus stalk of membrane receives refines and ships product made by the cell; Vesicles – little small bubbles transport materials; mitochondria – capsule shaped with innerfolds converts glucose into ATP all eukaryotes, nucleus is mitochondria; chloroplasts – oval shaped full of chlorophyll absorbs sunlight and makes glucose and oxygen all plants and algae; lysosomes – animal cells and animal like cells contain digestive enzymes clean up crew break down and recycle worn out cell parts; vacuole – small vacuole animals large plants store food water and waste storage area maintain internal water balance no water vacuole shrinks; cytoskeleton – protein filaments look like straws, thread like structures internal support internal movement of organelles; cilia and flagella – movement short hairlike structures, line cells of respiratory tract, protozoa little one celled organism paramecium flagella 1 or 2 few long tails sperm What is the composition of cytoplasm – like jello, runny mostly water sugar salt gases proteins lipids VI. The Plasma Membrane Regulate what enters and leaves the cell, separates internal cell parts from the external; thing and flexible always moving
Phospholipid Bilayer – composed of a head phosphate part hydrophilic two tails non polar hydrophobic bilayer double later arrangement of heads and tails heads pointing outwards tails pointing inward Carbohydrate chain – hold enzymes and hormones in cell, holds cells together
Cholesterol – keep membrane flexible, patch materials Proteins – structural support helps cell keep its shape, recognition recognizes and identifies other cells, communication send out signals to other cells transport acts as a gate different materials can pass through here
Passive Transport – high concentration to low concentration, no energy required diffusion move molecules from high concentration to low concentration; osmosis – movement of water from an area of high water concentration to low water concentration strictly movement of water Isotonic solution – two solutions have equal concentrations of solute ISO PERFECT Hypotonic solution – lower concentration solute than the cell hypOtonic swells Hypertonic solution – higher concentration of solute than the cell Hypertonic shrinks Facilitated diffusion – transport of some molecules from high concentration to low concentration using transport protein; glucose, amino acids, real small proteins; membrane proteins are specific one protein for glucose, diff one for amino acids H->L
Active transport – any movement of particles across the plasma membrane that does require energy that is from low concentration to high concentration L->H yes energy is required molecule against concentration gradient nerve impulses brain and thinking ATP requires energy large proteins food and bacteria
Endocytosis – movement of materials into the cell white blood cells examples destroy bacteria, one celled organism protozoa
Exocytosis – movement of materials out of the cell any materials cell makes Salt water is hypertonic, flexible, bendy; water is hypotonic vinegar – hypotonic, corn syrup hyper tonic, distilled water hypotonic III. Chapter 4 Energy and Life Energy – ability to do work Work – movement of an object across the distance Forms of energy – heat, light, sounds, chemical, mechanical, electrical All living things require a constant supply of energy; active transport, cell division, more organelles in the cell; individual level: grow, reproduce, respond to environment Energy flow is one way Reactants – starting materials glucose + O2 Products – what you are making Co2 + H2O Endothermic reactions – chemical reaction that absorbs energy; energy of the products is greater; uphill reaction; temperature decrease – cool down; energy must be added during entire reaction; cooking, baking soda and vinegar temp drops Exothermic reaction – chemical reaction that releases energy; energy of the reactants is greater; downhill reaction; temp increase – warmer released heat, light, sound, electricity give off heat; a match Activation energy – minimum amount of energy needed to start a reaction; match striking the match Catalyst – substance that speeds up a chemical reaction without being consumed; can be used again Enzyme – are proteins and are specific; catalyze only one reaction, lock and key, enzymes name is from the reaction lactose to lactase maltose to maltase; enzymes are proteins they have a specific shape which can be denatured by several factors: temp change, pH change, chemicals in environment; cooking (temp) lime juice to avocados (ph change) alcohol (chemicals) ATP – adenosine triphosphate ATP – has three phosphates – storing energy ADP – has 2 phosphates – energy released ADP – partially charged battery ATP – fully charged battery Cells can regenerate ATP as needed by using glucose Photosynthesis – process by which some organisms transform light energy into chemical energy stored in the bonds of sugar Overall reaction: carbon dioxide + water / reactions + light energy → glucose + oxygen gas/ products Chemical Equation: 6 CO2 + 6 H2O + energy —> C6H12O6 + 6 O2 Reaction is actually a series of steps controlled by enzymes
All things we call producers: plants, algae, blue green bacteria When a chlorophyll molecule absorbs light energy, electrons become excited and jump to higher electron shells Two reactions of photosynthesis; light reaction requires light, in the thylakoids, water splits to form oxygen, also produces ATP & high energy electrons/ Calvin Cycle – no light required by light reaction to start; in the space stroma, carbon dioxide is used to make sugars Cellular Respiration – process that breaks down glucose in the presence of oxygen to release energy Glucose + oxygen gas → carbon dioxide + water/products + energy C6H12O6 + 6 O2 → 6 CO2 + 6H20 +36 ATP Reaction occurs as a series of steps controlled by enzymes; energy is released slowly
All eukaryotes and most prokaryotes Aerobic cellular respiration – requires oxygen; three separate stages; glycolysis – all cells in your cytoplasm all cells have this, glucose (6 carbons) breaks in half, 2 ATP produces; Krebs – mitochondria, pyruvic acid produces carbon dioxide, 2 ATP; electron transport chain – mitochondria, 32 ATP, final products are carbon dioxide & water One molecule of glucose produces 36 ATP Fermentation – energy is harvested from sugar without oxygen
First reaction is Glucose → Pyruvic Acid + 2 ATP – both aerobic and anaerobic Alcohol Fermentation – yeast and some bacteria, Pyruvic Acid → alcohol + co2, breweries, petroleum companies, bakeries Lactic Acid Fermentation – animal muscle and some bacteria Pyruvic Acid → lactic acid, yogurt, sour cream
Energy from food we eat – large molecules must be broken down to smaller molecules (carbohydrates, fats, proteins) these small molecules are transported to the cells where they join the reactions of cellular respiration, ATP is needed to power all of lives activities (carbohydrates sugars starches) (fats glycerol and fatty acids) (proteins individual amino acids) Comparison of photosynthesis and respiration: Photosynthesis – occurs only in the presence of chlorophyll and light
Respiration – occurs in all cells and goes on with or without light P – stores energy into sugars (endo) R – releases energy from sugars (exo) P – Co2 and H2o are raw materials R – Co2 and H2o are products P – glucose and o2 are products R – glucose and o2 are raw materials Chapter 11. Human Body Systems Cell – smallest structural unit that has the properties of life Tissue – group of similar cells that perform a common function Organ – group of tissues that perform a common function Organ systems – group of organs that perform a common function Organism – depends on the coordination of all the organ systems for survival
Epithelial – cover body surfaces, ex: skin, lines digestive trap lines blood vessels; structure: closely packed cells one layer to several layers no blood vessels replaced frequently; functions: protection, transport materials through the cell, glands that secrete sweat glands salivary Muscle – specialized contract function: movement
Nerve – specialized for the rapid conduction of messages; functions: coordinate all your body processes, detect and respond to changes in internal and external environment Connective – structure cells in solid, liquid, or semi solid jelly like function hold your body parts together structure and support specialized connective tissue Bone – blood vessels, nerves looks like a mosaic of circles Cartilage – ear and nose for structure leopard print kind of
Fat – embedded in cells in semisolid material insulation cushion your organs tons of oval shapes little skinny ones left side
Blood – cells in liquid material transport materials to the cells remove waste from the cells looks like potatoes Homeostasis – process by which an organism keeps its internal conditions stable Negative feedback – the process in which the result of a process stops or reverses that same process
Negative feedback – body temperature – too hot – turn on ac – cool air produced – room temp drops – neg feed- control center
“Too hot! → skin sweat gland blood vessels dilating, sweating → heat released from body → body temp drops → brain
“Too cold” → skin blood vessels constricting, shivering, metabolic rate increasing → heat conserved → blood temp rises → neg feed→ brain
Integumentary System – consists of skin, hair, nails, scaly skin alligator, feathers Functions – protect from injury and infection, water loss or dehydration, ultraviolet radiation from the sun, helps regulate body temperature Epidermis – thin outermost layer no blood vessels in it Upper surface – flat, dead epithelial cells these are the ones that you shed Lower surface – living growing cells keratin and melanin located Keratin – skin hair and nails, fibers coiled, keeps your skin and hair waterproof
Melanin – brown pigment protein skin hair and eye coloring protects us from UV rays Elastin – stretch, flexible Collagen – strength and support, both decrease with age sun exposure smoking wrinkles skin sags Hair follicle – living growing cells very fast need food and oxygen blood vessels and nerves attached