Topic 2 Biology Study guide

Cellulose, Amylose, Amylopectin, Glycogen

http://andrewpover.co.uk/biology/ocr-as-biology-amylose-amylopectin-cellulose-and-glycogen-comparison-table/ Comparison Table

Describe the shape of the curve for an action spectrum

http://ib.bioninja.com.au/_Media/absorption-and-action-spect_med.jpeg

D ribose

https://commons.wikimedia.org/wiki/File:DL-Ribose.svg (image)

Describe the shape of the curve for an absorption spectrum

https://qph.fs.quoracdn.net/main-qimg-ec7318f0497381d8b83290f0eeaa3b23-c

Explain the role of random collisions in the binding of the substrate with the enzyme active site.

in most reactions, substrates are dissolved in water and the particles are in constant, random motion (brownian motion) ∙ these substrate particles will collide with enzymes and if the angle is correct, the substrate can bond with the active site on the enzyme. ∙ substrate molecules are smaller than the enzyme and moving faster as well. This random motion is responsible for collisions and eventual catalyst of the substrate.

Methane vs. Water

like water, is also a held together by covalent bonds, however the sharing of electron pairs is equal- it has no lone pairs of electrons. ... Since methane molecules are nonpolar and do not form hydrogen bonds, they have different thermal properties than those of water.

Steroids

lipids characterized by a carbon skeleton consisting of four fused rings

Membrane bound globular proteins

lobular proteins are folded such that their tertiary structure consists of the polar, or hydrophilic, amino acids arranged on the outside and the nonpolar, or hydrophobic, amino acids on the inside of the three-dimensional shape. This arrangement is responsible for the solubility of globular proteins in water.

Explain how nucleotides can connect to form a nucleic acid polymer

nucleotide's attach to one another to form a chain as a result of condensation reactions forming connecting phosphodiester/Covalent bonds

Structure of an Atom

nucleus made up of protons and neutrons; the electrons make up the surrounding area

Reflection: Overall, which number best represents your understanding of the content? What are you going to do that will expand your knowledge and assist you in better understanding this content?

out of ten... zero

define "anaerobic respiration"

partial breakdown of glucose in the cytosol for a small yield of ATP

Define photosynthesis

process in which cells synthesize organic compounds (eg glucose) from inorganic molecules (CO2 and H2O) in the presence of sunlight.

Hydrolysis reaction

reactions involve breaking polymer molecules such as polypeptides (large proteins) or starches into their monomer forms (amino acids and glucose molecules respectively). This can only be done when water is added to each of the bonds between the monmer molecules

Identify and label the 5' and 3' ends on a DNA or RNA diagram. Describe the meaning of "semi-conservative" in relation to DNA replication

semi-conservative= Produce two copies that each contained one of the original strands and one new strand.

define "limiting factor"

the factor that limits the reaction rate in any physiological process governed by many variables. 2 : the environmental factor that is of predominant importance in restricting the size of a population.

state the condition in which humans would perform anaerobic respiration

the lungs and blood system supply oxygen to most organs of the body rapidly enough, except sometimes muscles. When exercising at high intensity, cell demand will exceed available supplies of O2 can supply aerobically. Hence muscles will start breaking down glucose anaerobically to supply ATP rapidly for a short period of time

Define translation

the process of protein synthesis where the genetic info in mRNA is translated into a sequence of amino acids on a polypeptide chain

Define transcription

the process of using a DNA sequence as a template to create an RNA sequence

state the range of wavelengths that fall within the visible spectrum

white light 400-700 nm

Outline the role of messenger RNA in translation

carries coded instructions from DNA strand

State the number of amino acids used by living organisms to make polypeptides

20 amino acids

state the location of aerobic respiration

Eukaryotic cell- mitochondria

State the location of translation in the cell

cytoplasm

State three reasons why cellular respiration must be continuously performed by all cells

-All processes release heat energy and hence all energy eventually ends up as heat -The heat energy initially can be used to raise the temperature of the organism -Eventually it is lost to the environment and cannot be used for metabolic processes.

Outline the process of transcription, including the role of RNA polymerase and complementary base pairing.

-RNA polymerase separaties the DNA strands and synthesises a complementary RNA copy from one of the DNA strands -WHen the DNA strands are separated, ribonucleic triphosphates align opposite their exposed complementary base parther -RNA polymerase removes the additional phosphate groups and uses the energy from this cleavage to covalently join the nucleotide to go the growing sequence -Once the RNA sequence has been synthesised, RNA polymerase detaches from the DNA molecule and the double helix reforms

Outline the role of complementary base pairing between mRNA and tRNA in translation

-Ribosomes bind to mRNA in the cytoplasm and move along the molecule in a 5'-3' direction until it reaches a start codon (AUG) -Anticodons on tRNA molecules align opposite appropriate codons according to complementary base pairing (e.g. AUG=UAC) -each tRNA molecule carries a specific amino acid (according to the genetic code)

list three situations in which anaerobic respiration is useful

1) Short but rapid bursts of ATP production is needed 2) When oxygen supplies run out in respiring cells. 3) Environments that are deficient in oxygen, for example waterlogged soil

state three example uses of cellular energy

1) synthesizing large molecules like DNA, RNA, proteins. 2) Pumping of molecules or ions across the membrane via active transport 3) Moving thing inside the cell (chromosomes, vesicles, protein fibers

Amylose Starch

1,4 linkage unbranched

Amylopectin Starch

1,6 linkage branched

Describe the movement of DNA polymerase along the DNA template template strand

5' to 3'

state the chemical equation for photosynthesis.

6CO2 +12H2O =>(light and chlorophyll) C6H12O6+ 6O2+ 6H2O

Contrast competitive and noncompetitive enzyme inhibition.

A competitive inhibitor will block the enzyme's active site (ie: it will occupy the same space as the natural substrate, blocking it from being catalyzed). A non-competitive inhibitor will bind to the enzyme somewhere other than the active site of the enzyme; an allosteric site.

Disaccharide

A double sugar, consisting of two monosaccharides joined by dehydration synthesis. Ex. sucrose, lactose, and maltose.

Relationships between genes and polypeptides

A gene mutation typically results in the substitution of a different amino acid into the polypeptide sequence of a protein. Gene-protein relations - An Introduction to Ge Living organisms can only produce a fraction of amino acid sequences - amino acid sequence of each polypeptide is stored in a coded form in the base sequence of a gene 3 bases of a gene code for one amino acid - genes are always longer than required with extra base sequences at both ends and at certain points in the middle.

Polymer

A long molecule consisting of many similar or identical monomers linked together. A large molecule consisting of many repeating chemical units or molecules linked together.

Monomer

A simple compound whose molecules can join together to form polymers The subunit that serves as the building block of a polymer.

Identify the four bases of DNA based on the numbers of rings (purines or pyrimidines) and the number of hydrogen bonds it can form

Adenine and Guanine: Purines have 2 rings. Thymine and Cytosine: 1 ring. (refer to diagram for number of hydrogen bonds)

state the reaction for cellular respiration

Aerobic uses O2 to completely break down glucose in the mitochondria for a larger ATP yield Anaerobic involves partial breakdown of glucose in the cytoplasm for a small yield of ATP.

Contrast of Ionic, Covalent, and Hydrogen bonds

All bonding involves electrons or the charges that result from the giving/taking of electrons. Ionic bond: attraction between cation and anion (no sharing of electrons) Covalent bond: electrons are shared between two atoms. Hydrogen bond: (not a true "bond" ) attraction between polar molecules. http://hyperphysics.phy-astr.gsu.edu/hbase/Chemical/bond.html (comparison)

Distinguish between an action spectrum and an absorption spectrum

An action spectrum is the rate of a physiological activity plotted against wavelength of light. It shows which wavelength of light is most effectively used in a specific chemical reaction. Some reactants are able to use specific wavelengths of light more effectively to complete their reactions. An absorption spectrum is a spectrum of electromagnetic radiation transmitted through a substance, showing dark lines or bands due to absorption of specific wavelengths.

Explain how and why industrial enzymes are often immobilized

An immobilized enzyme is an enzyme attached to an inert, insoluble material—such as calcium alginate (produced by reacting a mixture of sodium alginate solution and enzyme solution with calcium chloride). This can provide increased resistance to changes in conditions such as pH or temperature.

compare the total amount of ATP made from anaerobic and aerobic respiration

Anaerobic respiration makes a total of 2 ATP. Aerobic respiration is much more efficient and can produce up to 38 ATP with a single molecule of glucose.

Explain how pH affects the rate of enzyme activity. Draw a graph to represent this.

As pH levels increase or decrease from the optimum pH, the activity level is reduced. Both acids and alkalis can denature enzymes. optimum pH = 7 exception = pepsin

Catabolism

Metabolic pathways that break down molecules, releasing energy. breakdown of more complex substances into simpler ones with release of energy

Contrast of Anabolism and Catabolism

Catabolic processes break down complex compounds and molecules to release energy. This creates the metabolic cycle, where anabolism then creates other molecules that catabolism breaks down, many of which remain in the organism to be used again.

Anabolism

Metabolic pathways that construct molecules, requiring energy. Constructive metabolism; the process of building up larger molecules from smaller ones. Process of building up complex materials (proteins) from simple materials

Calculate BMI using formula and nomogram

Body mass index - Mass (kg)/ Height (m)

Compare the structure of DNA and RNA

Both are made up of monomers called nucleotides, contain pentose sugars, have nitrogenous bases A, G, C, have phosphate groups in their nucleotides, both have base pairs G and C, both are necessary for the cell to produce proteins

Explain the relationship between enzyme structure and enzyme specificity, including the role of the active site.

Enzymes bind with chemical reactants called substrates. There may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. In some reactions, a single-reactant substrate is broken down into multiple produc

Explain how temperature affects the rate of enzyme activity. Draw a graph to represent this.

Enzyme activity will increase as temperature increases. ∙ At higher temperatures, more collisions occur between the substrate and the enzymes due to faster movement of molecules. At extreme high temperatures, enzymes can denature (change conformational shape) and will stop working. High heat causes vibrations inside the enzymes which breaks bonds needed to maintain the structure of the enzyme.

Generalized formula of carbs

CH2O

Monosaccaride

Carbohydrate made up of a single sugar unit Ex. glucose, fructose and galactose

Polysaccharide

Carbohydrates that are made up of more than two monosaccharides Ex. storage polysaccharides such as starch and glycogen, and structural polysaccharides such as cellulose and chitin

4 major classes of carbon compounds used by living organisms

Carbohydrates, lipids. nucleic acids and proteins

Outline the number and type of bond carbon can form with other atoms

Carbon forms 4 single bonds with other atoms. They are covalent bonds.

Cause and effect of the polar nature of water

Cause: In a polar bond, some of the electrons binding the constituent elements are shared unequally, meaning they tend to be attracted more to one atom than the other. This causes a partial negative and positive charge in the atoms, creating what is called a dipole. Polar bonds in an unsymmetrical arrangement make a molecule polar. the unsymmetrical, v-shaped hydrogen-oxygen-hydrogen bond makes the hydrogen-heavy side of the molecule positive and the oxygen side negative. This is because the negatively charged electron in each hydrogen atom is slightly more attracted to the oxygen atom. Although the overall charge of the molecule is neutral, the molecule is polar because of this arrangement. The bonds among the atoms in water are covalent bonds where two atoms share pairs of electrons with each other. In water, two of oxygen's six electrons are shared--one each with the two hydrogen atoms. Effect: Polarity determines most of its essential properties: melting point, boiling point, surface tension, capillary action and solubility. It also establishes how it interacts with other molecules. Water's polarity makes it an excellent solvent. This means that it can easily bond with other molecules, including itself. This ability to bind to itself, called hydrogen bonding, is essential to its common liquid form and is also essential to water's relatively strong surface tension.

State the effect of denaturation on enzyme structure and function

Changing the shape of the active site of an enzyme will cause its reaction to slow down until the shape has changed so much that the substrate no longer fits. When this happens the reaction stops. At this point we say the enzyme is denatured and is permanently damaged.

state the primary and accessory pigments found in chloroplasts

Chlorophylla-a is the primary pigment for photosynthesis in plants, but the range of light absorption is extended by chlorophyll-b, beta-carotene and other accessory pigments. Accessory pigments include Anthocyanins, Xanthophylls, Carotenoids, and Chlorophyll B.

Cis and Trans fatty acids

Cis configuration: Hydrogen bonds are on the same side as the double bonded carbon atoms. Only have one carbon double bond which gives it a kink. Liquid at room temperature and have low melting points. Trans configuration: Hydrogen atoms are on opposite sides in structure. High melting point and solid at room temperature

Dehydration Synthesis ( describe reactions)

Condensation reaction where molecules are connected by the loss of a water molecule. In the process, a water molecule is formed. Dehydration reactions involve monomer molecules (like amino acids or simple sugars) bonding to each other. When they bond, an OH and an H (H2O) are removed from them. Because the newly bonded molecule loses water, this is known as dehydration.

Explain the need to controlled variables in experimental design.

Controlled variables provide a concrete basis of the experiment and provide a concrete procedure that can be repeated.

Describe functions of enzyme proteins

Enzymes carry out almost all of the thousands of chemical reactions that take place in cells. They also assist with the formation of new molecules by reading the genetic information stored in DNA

State the two types of nucleic acid

DNA and RNA

State the names of the nitrogenous bases found in DNA and RNA

DNA: Thymine, Adenine, Guanine, Cytosine. RNA: Uracil, Adenine, Guanine, Cytosine

Effect of Ph and heat on protein structure

Denatured protein = does not return to former structure and is permanent * Soluble proteins usually become insoluble and form a precipitate due to hydrophobic r groups being exposed to water * Heat causes vibrations which break the weak bonds * pH both acidic and alkaline can cause denaturation as charges on R groups are changed to form new ionic bonds causing a new confirmation/

list mechanism for measuring the rate of photosynthesis

Direct methods involve the measurement of the amount of O2 released or the amount of CO2 consumed.

Define antiparallel in relation to DNA structure

Each strand is parallel but moving or oriented in opposite directions. One side moves 5' to 3', while the other moves 3' to 5'.

Explain how substrate concentration affects the rate of enzyme activity. Draw a graph to represent this.

Enzyme activity is directly proportional to substrate concentration at low concentration levels. As the concentration of the substrate increases, the enzyme activity increases because random collisions of substrate molecules. Enzymes increase as the concentration of the substrate increases. At high substrate concentrations, all the active sites of the enzymes will be occupied, therefore, increasing concentration will no longer have an effect (plateau).

Ten functions of proteins in a cell or organism

Enzymes(speed up the rate of reactions) Muscles (actin and myosin) Collagen (hair) Skin Fingernails Insulin Antibodies (defense) Hemoglobin (blood) Membrane Proteins (transport) Ovalbumin (egg whites, supports embyro)

Structure of globular proteins vs. fibrous proteins

Fibrous proteins are generally composed of long and narrow strands and have a structural role (they are something) Globular proteins generally have a more compact and rounded shape and have functional roles

Proteome vs. Genome

Genomics is the study of the genes in an organism while Proteomics is the study of the all the proteins in a cell. Proteomics studies are more beneficial because proteins are the functional molecules in cells and represent actual conditions

State the complementary base pairing rules.

In DNA, Thymine pairs with Adenine. In RNA, Uracil pairs with Adenine. Guanine and Cytosine always pair with each other.

compare anaerobic respiration in yeasts and humans

In humans, glucose is converted to lactic acid, which is usually in a dissolved form known as lactate. In yeast and plants, glucose is converted to ethanol and carbon dioxide. Both forms are toxic in excess, therefore must be removed or kept at small quantities.

Polar and ionic molecules are hydrophyllic

In most cases

Tertiary Structure of a protein

Ionic Bond will have a single polypeptide chain "backbone" with one or more protein secondary structures, the protein domains. Amino acid side chains may interact and bond in a number of ways. The interactions and bonds of side chains within a particular protein determine its tertiary structure.

Quaternary Structure

It is the linking together of two or more poly peptides to form a single protein. Results from two or more polypeptide subunits. Quaternary structure is the arrangement of more than one protein molecule in a multi-subunit complex.

Effects of high or low BMI

Low BMI- if your low BMI is caused by an unbalanced diet or an underlying disease that affects nutrient absorption. Malnutrition can also lead to anemia or a deficiency in essential vitamins. Anemia can also be caused by malabsorption of nutrients High BMI- obesity is defined as a BMI equal to or greater than 30. If you fall in the obese range according to the guidelines, you are at increased risk for heart disease and need to lose weight.

Identify and manipulated, responding and controlled variables in descriptions of experiments testing the activity of enzymes.

Maniupulated variable- conditions in which the enzyme may be reactant upon when paired with substrate Responding Variable- Product containing enzyme of substrate Controlled Variable- Same enzyme & substrate. Same size test tubes. Same amount of time for enzyme activity. Same pH. Same enzyme & substrate. Same size test tubes. Same amount of time for enzyme activity. Same temperature.

Alpha Glucose

OH on bottom has a hexagonal shape with (from top left to bottom right): H, HO, O, H and OH All monomers are the same orientation. This polysaccharide is less rigid and is used in starch.

Beta Glucose

OH on top has a hexagonal shape with (from top left to bottom right): H, HO, O, OH and H Every other monomer is flipped. This polysaccharide is more rigid and used in cellulose

State the two functions of tryglcerides

One of the very important functions of triglycerides and, even more so, the related phospholipids is that they contribute to the structure of membranes by the formation of a lipid bilayer. The membranes serve as a barrier to keep separate the inside of a cell and the outside of a cell. Triglycerides provide your body with energy, but their main function is to store energy for later use. The food you eat contains calories in the form of carbohydrates, protein and fat. ... Fat cells hold the triglyceride molecules until your body needs energy, such as between meals.

Outline the parts of a nucleotide

Phosphate group, sugar (5-carbon), nitrogenous base (A)

define pigment

Pigments absorb light as a source of energy for photosynthesis.

explain why plants are green

Plants are green because their cells contain chloroplasts which have the pigment chlorophyll which absorbs deep-blue and red light, so that the rest of the sunlight spectrum is being reflected, causing the plant to look green.

state that (some) prokaryotes, algae and plants carry out photosynthesis

Plants, algae and cyanobacteria all conduct oxygenic photosynthesis. That means they require carbon dioxide, water, and sunlight (solar energy is collected by chlorophyll).

Describe hydrolysis reactions

Polymers are broken down into monomers in a process known as hydrolysis, which means "to split water," a reaction in which a water molecule is used during the breakdown. During these reactions, the polymer is broken into two components.

Proteome

Proteome = all of the proteins produced by a cell, a tissue or an organism. To find out how many different proteins are being produced, mixtures are extracted from a sample and are separated by gel electrophoresis. Antibodies identify whether a particular protein is present. Proteome is variable because different cells in an organism make different proteins.

Identify nitrogenous bases by either a pyrimidine or purine.

Pyrimidines: Cytosine, Thymine, Uracil Purines: Adenine, Guanine

Given the image of an amino acid, classify the amino acid and the chemical properties based on the R group properties

R groups give the polypeptide its character, because of their differences, the twenty amino acids are chemically diverse. Some proteins contain amino acids that have been modified after the polypeptide has been synthesised

calculate the Rf value for pigments using pigment chromatography

Rf = 0.16 for xanthophyll, Rf = 0.32 for chlorophyll b, Rf = 0.44 for chlorophyll a, and Rf = 0.95 for β- carotene.

State the function of the following proteins:

Rubisco = Enzyme that catalyzes the reaction which fixes carbon dioxide, provides the source of carbon which all carbon compounds living things require can be produced. Immunoglobulin = Proteins known as antibodies which bind to the pathogen and cause a response. The body produces a large range of immunoglobulins Collagen = Rope like proteins which a quarter of our human bodies contain, forming a mesh of fibers in skin and blood vessel walls that resists tearing - bundles give ligaments and walls immense strength and form part of teeth and bones. Rhodopsin = Pigment that absorbs light that is a membrane protein of rod cells of the retina. Consists of a retinal molecule surrounded by opsin polypeptide. When a retinal molecule absorbs light it changes shape causing a change in opsin that sends a nerve impulse to the brain, allowing low light intensities to be detected. Insulin = Hormone produced to signal to cells to absorb glucose to reduce blood glucose levels. These cells have a receptor for insulin which the hormone can bind to reversibly. Shape and properties of insulin correspond precisely to receptor. Insulin secreted from the pancreas. Spider silk = Dragline silk made by spiders containing regions where polypeptides form parallel arrays and other regions with disordered tangle. When stretched it extends and is very resistant to breaking. Actin-the most abundant protein in most eukaryotic cells. ... Moreover, the interaction of filamentous actin with myosin forms the basis of muscle contraction. Owing to its central role in the cell, the actin cytoskeleton is also disrupted or taken over by numerous pathogens. Myosin- Myosin is the prototype of a molecular motor—a protein that converts chemical energy in the form of ATP to mechanical energy, thus generating force and movement. Casein-The main protein present in milk and (in coagulated form) in cheese. It is used in processed foods and in adhesives, paints, and other industrial products. Hemoglobin-a red protein responsible for transporting oxygen in the blood of vertebrates. Its molecule comprises four subunits, each containing an iron atom bound to a heme group. Acetylcholine receptor- ion channels embedded in cell membranes, capable of switching from a closed to open state when acetylcholine binds to them; in the open state they allow ions to pass through. Oxytocin- a hormone that acts on organs in the body (including the breast and uterus) and as a chemical messenger in the brain, controlling key aspects of the reproductive system, including childbirth and lactation, and aspects of human behaviour. Prolactin-enabling mammals, usually females, to produce milk. Ferrtin-a protein produced in mammalian metabolism that serves to store iron in the tissues. Bilirubin-an orange-yellow pigment formed in the liver by the breakdown of hemoglobin and excreted in bile. Fibrinogen-a soluble protein present in blood plasma, from which fibrin is produced by the action of the enzyme thrombin. Transferrin- The main role of transferrin is to deliver iron from absorption centers in the duodenum and white blood cell macrophages to all tissues. Albumin- simple form of protein that is soluble in water and coagulable by heat, such as that found in egg white, milk, and (in particular) blood serum.

What role do enzymes play in metabolism?

Some enzymes help to break down large nutrient molecules, such as proteins, fats, and carbohydrates, into smaller molecules. This process occurs during the digestion of foodstuffs in the stomach and intestines of animals. ... Each enzyme is able to promote only one type of chemical reaction.

Outline the three stages of enzyme activity.

Stage 1. ∙ the substrate binds to an active site of the enzyme ∙ there are some enzymes which have different parts to their active site and it can bind two substrates Stage 2 ∙ substrates change into different chemical substances (the product) while they are still bound to the active site. Stage 3 ∙ the active site releases the product and it is free to catalyse another substrate.

Glycogen

Storage form of glucose Energy storage in animals Polysaccharide

Primary structure of a protein

The primary structure of a protein refers to the sequence of amino acids in the polypeptide chain. The primary structure is held together by peptide bonds order of amino acids held together by covalent bonds

Describe the action of DNA polymerase III in pairing nucleotides during DNA replication

Synthesizes the new strand by adding nucleotides onto the primer

Catalysis

The acceleration of a chemical reaction by a catalyst The process of speeding up the rate of a chemical reaction Enzymes speed up chemical reactions The process of changing the rate of a chemical reaction by the action of a catalyst.

Metabolism

The combination of chemical reactions through which an organism builds up or breaks down materials

Structural difference between alpha and beta glucose

The difference between alpha and beta glucose is nothing more than the position of one of the four -OH groups. The carbon to the right of the oxygen atom in the hexagonal ring is called the anomeric carbon. If the -OH group attached to it is below the ring, the molecule is alpha glucose.

outline the process of separating pigments using chromatography

The eluant (carrier gas) is introduced from a gas cylinder outside the machine. It's called the carrier because that's exactly what it does—carry the sample we're studying through the machine. In gas chromatography, the carrier gas is the mobile phase. The rate of flow of the carrier is carefully controlled to give the clearest separation of the components in the sample. The carrier enters the machine through an inlet port/splitter. The sample being measured is injected into the carrier gas using a syringe and instantly vaporizes (turns into gas form). The gases that make up the sample separate out as they move along the column (orange), which contains the stationary phase (typically, it's a thin coating on the inside wall of the column). The column is a very thin (capillary) tube, sometimes as much as 30-60m (100-200ft) long, coiled and entirely contained inside an oven (blue) that keeps it at a high enough temperature to ensure that the sample remains in gas form. The temperature of the oven can be carefully controlled. As the sample separates out and its constituent gases travel along the column at different speeds, a detector senses and records them. Various different detectors can be used, including flame ionization detectors, thermal conductivity detectors, and mass spectrometers (usually separate machines). The data analyzer/recorder attached to the machine draws a chromatogram (chart) with peaks corresponding to the relative amounts of the different chemicals in the sample.

outline energy transfer in the formation and use of ATP

The energy is immediately available Released by splitting ATP into ADP and phosphate -> can be reconverted back to ATP through cell respiration. One molecule of ATP contains three covalently linked phosphate groups - which store potential energy in their bonds When ATP is hydrolysed (to form ADP + Pi) the energy stored in the phosphate bond is released to be used by the cell Cell respiration uses energy stored in organic molecules to regenerate ATP from ADP + Pi (via oxidation)Most energy is converted to heat within a cell - no reusable for cell activities/ eventually lost to the environment

Define and state evidence for the "Great Oxidation Event"

The event occured 2.3 billion years ago, when photosynthetic organisms began to saturate the environment with oxygen. Initally Earth had high levels of dissolved iron. When reacted with oxygen it creates a solid, helping to give a timeline of when oxygen became prominent.

state the relationship between wavelength and energy

The greater the energy, the larger the frequency and the shorter (smaller) the wavelength. Given the relationship between wavelength and frequency — the higher the frequency, the shorter the wavelength — it follows that short wavelengths are more energetic than long wavelengths.

Where and how is water able to form hydrogen bonds?

The partial negative charge on the O of one molecule can form a hydrogen bond with the partial positive charge on the hydrogens of other molecules. Water molecules are also attracted to other polar molecules and to ions.

Celluose

The polysaccharide of glucose that forms plant's cell walls

Outline the source and use of pharmaceutical insulin prior to the use of gene transfer technology

The set of DNA and RNA sequences that determine the amino acid sequences used in the synthesis of an organism's proteins. It is the biochemical basis of heredity and nearly universal in all organisms. The same genetic code appears to operate in all living things, but exceptions to this universality are known. Since the same codons code for the same amino acids in all living things, genetic information is transferrable between species. The ability to transfer genes between species has been utilised to produce human insulin in bacteria (for mass production) The gene responsible for insulin production is extracted from a human cell It is spliced into a plasmid vector (for autonomous replication and expression) before being inserted into a bacterial cell The transgenic bacteria (typically E. coli) are then selected and cultured in a fermentation tank (to increase bacterial numbers) The bacteria now produce human insulin, which is harvested, purified and packaged for human use (i.e. by diabetics)

Molecular Biology

The study of biological structures, functions, and heredity at the molecular level.

Define visible light

The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light.

Outline production of lactate in humans during anaerobic respiration

There is a limit to the concentration of lactate that the body can tolerate, which limits how much and how long anaerobic can be performed. We often feel a burn in our body when that happens. Afterwards, the lactate must bebroken down which involved the use of oxygen that builds up during a short period of anaerobic respiration called the Oxygen Debt

How can the effects of lipids on health be assessed scientifically?

Through the consumption of fats in its presence in the bloodstream Fats and cholesterol cannot dissolve in blood and are consequently packaged with proteins (to form lipoproteins) for transport Low density lipoproteins (LDL) carry cholesterol from the liver to the rest of the body High density lipoproteins (HDL) scavenge excess cholesterol and carry it back to the liver for disposal Hence LDLs raise blood cholesterol levels ('bad') while HDLs lower blood cholesterol levels ('good') High intakes of certain types of fats will differentially affect cholesterol levels in the blood Saturated fats increase LDL levels within the body, raising blood cholesterol levels Trans fats increase LDL levels and decrease HDL levels within the body, significantly raising blood cholesterol levels Unsaturated (cis) fats increase HDL levels within the body, lowering blood cholesterol levels A positive correlation has been found between the intake of saturated fats and the incidence of CHD in human populations Counter: Certain populations do not fit this trend (e.g. the Maasai tribe in Africa have a fat-rich diet but very low rates of CHD) Intervention studies have shown that lowering dietary intakes of saturated fats reduces factors associated with the development of CHD (e.g. blood cholesterol levels, blood pressure, etc.) Counter: Validity of intervention studies is dependent on size and composition of cohort, as well as the duration of the study In patients who died from CHD, fatty deposits in diseased arteries were found to contain high concentrations of trans fats Counter: Genetic factors may play a role (e.g. blood cholesterol levels only show a weak association to dietary levels)

Explain the need for repeated measurements (multiple trials) in experimental design.

To determine the accuracy of an experiment and to rule out one-time instances.

Explain a condensation reaction connecting two monosaccharides in the formation of a disaccharide

Two monosaccharides are joined together and a molecule of water is removed. ... The two monosaccharides are bonded via a dehydration reaction (also called a condensation reaction or dehydration synthesis) that leads to the loss of a molecule of water and formation of a glycosidic bond.

Saturated vs. Unsaturated fatty acids

Unsaturated fatty acids have one or more double bonds between carbon atoms. (Pairs of carbon atoms connected by double bonds can be saturated by adding hydrogen atoms to them, converting the double bonds to single bonds. Therefore, the double bonds are called unsaturated.)

Types of molecules will dissolve

Water dissolves polar molecules with a +/- charge. Water will repel non-polar molecules, meaning they are hydrophobic, (oils, fats and greasy substances).

Why is water such a good solvent?

Water is capable of dissolving a variety of different substances, which is why it is such a good solvent. And, water is called the "universal solvent" because it dissolves more substances than any other liquid. This is important to every living thing on earth.

Three thermal properties of water that are useful to living organisms/Outline the benefits of water's high heat capacity, high heat of vaporization, and high boiling point

Water's solvent properties allows molecules to dissolve in it. This means that water can transport minerals up the xylem tube and sugars up the phloem tubes in plants. Blood in animals consists largely of water, allowing the transportation of oxygen, urea and glucose throughout the body. Water also is the site of metabolic reactions because reactions can occur between dissolved compounds. Water's polarity also inhibits movement of its molecules. Since all the molecules are connected, they cannot freely move about as other, non-polar molecules do. Heat, the kinetic energy of molecules, is thus restricted and so water has a high specific heat (it must absorb large amounts of energy in order to change states). This means that water can serve as a temperature insulator, and does so in organisms of all kinds. Water's high latent heat of vaporization is due to strong hydrogen bonds existing between water molecules. A large amount of heat is released when water in the liquid state vaporizes into the gaseous state. The boiling and freezing points of water enable the molecules to be very slow to boil or freeze, this is important to the ecosystems living in water

Denaturation

When the three dimensional structure of a protein is changed and can no longer function.

Secondary structure of a protein

Within the long protein chains there are regions in which the chains are organised into regular structures known as alpha-helices (alpha-helixes) and beta-pleated sheets. These are the secondary structures in proteins. These secondary structures are held together by hydrogen bonds.

Define "cell respiration"

a controlled release of energy from organic compounds

Phospholipids

a lipid consisting of a glycerol bound to two fatty acids and a phosphate group. make up cell membranes

explain how the following factors limit the rate of photosynthesis: a. temperature, b. light intensity, c. CO2 concentration

a: Photosynthesis is controlled by enzymes, which are sensitive to temp fluctuations. As temp increases reaction rate will increase, as reactants have greater kinetic energy and more collisions result. Above a certain temp the rate of photosynthesis will decrease as essential enzymes begin to denature. b: Light is absorbed by chlorophyll which convert the radient energy into chemical energy ATP. As light intensity increases reaction rate will increase , as more chlorophyll are being photo-activated. Different wavelengths of will have different effects on the rate of photosynthesis (eg green light is reflected). c: Carbom dioxide is involved in the fixation of carbon atoms to form organic molecules. As carbon dioxide concentration increases reaction rate will increase, as more organic molecules are being produced. At a certain concentration of CO2 photosynthesis rate will plateau, as the enzymes responsible for carbon fixation are saturated.

State the number of nitrogenous bases per complete turn of the DNA double helix

about 10 bases

Adhesion and Cohesion

adhesion refers to the clinging of unlike molecules and cohesion refers to the clinging of like molecules. Adhesion is the mutual attraction between unlike molecules that causes them to cling to one another.

Non-polar, and non- ionic molecules are hydrophobic

always

Energy Storage for Lipids and carbohydrates

carbohydrates are usually used for short term storage whereas lipids are used for long term storage. ... They also contain more energy per gram than carbohydrates which makes lipids a lighter store compared to a store of carbohydrates equivalent in energy.

state the types of organic compounds used in cellular respiration by animals and plants

carbohydrates (glucose), lipids and proteins can also be digested

Saturated Fatty Acid

fatty acid containing only single bonds a fatty acid whose carbon chain cannot absorb any more hydrogen atoms there are only single bonds between all carbon atoms in a fatty acid chain, has more hydrogen