Key Question Biology
Key Question Biology
1) Mg2+ Has 10 electrons.
2) Carbon -14 would not be effective at dating bones that are millions of years old. Carbon -14 is effective at dating to a maximum of 40 000 to 50 000 years old. The isotope decays over time and would not be present on bones that are millions of years old. 3) Hydrolysis – Water used to breakdown molecules. Hydro means water and lysis means to breakdown. An example of hydrolysis in action within our bodies is how our body breaks down protein into amino acids. Water is used to break protein down in to its amino acids.
Condensation- Condensation is when two molecules combine and form one bigger molecule. It is exact opposite process of hydrolysis. It is also called dehydration synthesis because water is removed “dehydrated” in forming of new molecule. This reaction happens in our bodies when we form muscle tissue.
Oxidization-Reduction (REDOX)- This reaction describes the process of transfer of electrons from one reactant to another. The gaining of electrons is known as reduction and losing electrons is called oxidization. It is usually referred to as REDOX (REDuction/OXidization). One example of redox within our bodies is during cellular respiration. Question 4 is a chemical equation representing this process.
Neutralization – Involves acids and bases and producing water and a salt. Acids contain Hydrogen Ions and Bases contain Hydroxide Ions. The best example of neutralization in our bodies is the carbonic acid bicarbonate buffer. It contains acid and base and maintains our bloods Ph level. If our blood becomes acidic or basic this buffer neutralizes conditions.
a) Carbon atoms in glucose are being oxidized
b) Oxygen is being reduced
Unit 1 Lesson 2 Key Questions
5)a) Carbohydrates monomer(s) is monosaccharide’s which are simple sugars. The functional groups of carbohydrates are carbonyl and hydroxyl. The linkage type is a glycosidic bind. Carbohydrates primary function is to provide energy for the body. b)Proteins monomer(s) are called amino acids. The functional groups are called aminos and carboxyls. The linkage type is by using a peptide bond. The primary function of protein is build and repairs the body. c)Lipids monomer(s) are called fatty acid and glycerol. The functional group is called ester. The linkage type of lipids is non polar bonds or sometimes called ester bonds. The primary function of lipids is energy, hormone production and insulation of the body. D)Nucleic Acids monomer(s) are called nucleotide. The functional group is dna(Deoxyribonucleic acid) and rna(Ribonucleic acid). The linkage type is covalent bonds and hydrogen bonds. The primary function of nucleic acid is to store and transfer genetic material.
Box on right illustrates the peptide bond resulting from the condensation of both the amino acids. The box on the left illustrates the separation of the hydroxide group from glycine and the hydrogen atom from valine. 7)a) You would do the Benedict’s reagent test for simple sugars and the Lugol’s solution or Iodine test for polysaccharides and starch. To test the lipids you would use the Sudan iV test and Biurets reagent test for protein. b) Benedict test the solution color will change from blue to pink/orange red, indicating simple sugars are present. Lugols test the solution color will change from yellowish brown to dark purple, indicating starch and polysaccharides are present. Sudan iV test the lipid content will turn into red, indicating lipids are present. Biuret test the solution colour will change from Blue to pink, indicating protein is present.
UNIT 1 Lesson 3 Key Questions
8) Enzymes are protein catalysts that speed up chemical reactions, without being consumed by the reactions themselves. For the reaction to occur, the reactions have to overcome the activation energy barrier. The enzymes work by lowering the activation energy. The two substrates are bounded and optimally positioned, the reaction can proceed to form or break chemical bonds. You must mention the presence of successive collisions.
9)a) Enzymes work in very limited temperature and Ph range. If Ph is altered even slightly it can slow down or completely stop the enzymes action. It is a concept known as enzyme specificity. When pH of a particular medium changes, it leads to alteration in the shape of the enzyme or the substrate and if denaturation occurs the process stops completely. b) The relationship between rate of reaction and concentration of substrate depends on the affinity of the enzyme for its substrate. The higher the substrate concentration the more quickly product is produced (rate of reaction increases) until enzyme saturation is reached at which time more substrate has no further effect. 10)Enzyme A the Optimal Ph seems to be Ph4 and Optimal Temperature seems to be 370 c. Enzyme B the optimal Ph seems to be Ph7 and the optimal temperature is a range between 40c -80oc. Enzyme C the optimal Ph seems to be a range between Ph1 and Ph 13 and the optimal temperature seems to be 200c.
11)Three benefits of enzymes in food technology are:
Alternatives to chemical based technology, can replace chemicals in many processes. This can allow real advances in the environmental performance of production processes, through lower energy consumption and biodegradability. More specific in action than synthetic chemicals. Processes which use enzymes therefore has fewer side effects and waste byproducts, producing higher quality products. Allow processes to be carried out which would otherwise be impossible. Like changing colour of food products or allowing products to be clear like apple juice uses pectinase enzyme.
Unit 1 Lesson 4 Key Questions
12) Mitochondria produce ATP or energy. Muscle cells contract and use energy at a rapid rate and require more ATP than a fat cell would require. Muscles are required for movement so each movement requires ATP and muscle cells in mammals also are sued to produce heat, also requiring more ATP. Fat cells are energy storage. 13)a) Diffusion does not require energy, Active Transport require energy or ATP. b)Diffusion goes from high to low concentration while active transport goes from low to high. 14) Receptor-mediated endocytosis has receptor, and is specific, only certain specific molecules can enter. Phagocytosis surrounds its food without really knowing what it is, cell membrane engulfs large molecule with a vesicle. 15) Integral proteins allow polar molecules like water to pass through the non polar interior of the membrane. Cholesterol makes the membrane sturdy and more rigid than it would be without.
16)A) The purpose of this experiment is to investigate the movement of water in and out of a carrot-osmometer as a result of being placed in two different solutions: distilled water, and a 10% salt solution. B) Beaker A contained distilled water Whenever there is movement of water, it is from a region of higher concentration to lower concentration. as there’s a fall in the water level in beaker B. This is because the cells of the carrot placed in beaker B have a lower water potential than the distilled water on the outside. So water molecules undergo osmosis from higher water potential to lower, from the outside water into the cells of carrot. This results in the fall in water level.
17) Salt water when used for rinsing mouth becomes hypertonic in relation to the fluid inside the cell of the gums that are swelled. As the fluid of two concentrations is separated by a semi-permeable membrane, osmosis starts to make a balance. In this process fluid comes out of the cells of the gums to make fluid in mouth isotonic to intracellular fluid. This helps reducing intracellular fluid and thus reducing the swelling of the gums.