LIFE OF CELL Jhia Anjela D. Rivera 1,2 1 BS Biology Graduate, Department of Biology, College of Science, Polytechnic University of the Philippines 2 MS Biology Student, Graduate School, Centro Escolar University
OBJECTIVES Relate basic concepts of chemistry in understanding biology Explain several properties of water that make it possible for life to exist Recall the four classes of organic molecules and illustrate their importance
OUTLINE Atoms, molecules, and Life Water Biological Molecules Carbohydrates Lipids Proteins Nucleic Acids
CHEMISTRY OF LIFE A biological system is just a big container of watery chemicals undergoing a continuous series of chemical reactions
MATTER Anything that has space and has mass Physical states: solid, liquid, gas Mass: amount of matter in an object
ELEMENT Simplest form of matter A substance that cannot be broken down into other substances by chemical reactions
ATOM Smallest unit of matter Smallest particle of an element Smallest unit of matter that still retains the properties of an element
STTRUCTURE OF AN ATOM Proton: + charge, inside nucleus Electron: - charge, outside nucleus Neutron: neutral, inside nucleus
STTRUCTURE OF AN ATOM Proton: + charge, inside nucleus Electron: - charge, outside nucleus Neutron: neutral, inside nucleus
STRUCTURE OF AN ATOM
STRUCTURE OF AN ATOM
MOLECULES 2 or more atoms chemically combined Ex. Water (H2O)
MOLECULES 2 or more atoms chemically combined Ex. Water (H2O)
LIFE Set of common characteristics that distinguish living organisms from non-living matter Possesses reproduction, growth, energy utilization, regulation Cannot exist without water Use water as the medium for the chemical reactions necessary to sustain life
WATER Solvent of life Main medium of the different chemical components of life Provides medium for chemical reactions
ORGANIC COMPOUNDS Carbon-based molecules Usually synthesized by cells
BIOLOGICAL MOLECULES Carbohydrates Lipids Proteins Nucleic Acids
CARBOHYDRATES Commonly known as carbs class of molecules that includes sugars and polymers of sugars Primary source of dietary energy and raw material for manufacturing other kinds of organic compounds (animals) Serve as a building material for much of the plant body (plants)
CARBOHYDRATES Characteristics of Carbohydrates Contain C, H, O H:O is a 2:1 ratio Ex. C 6 H 12 O 6 Monosaccharides are the building blocks. Monosaccharide: simple sugar (1 sugar) Ex. Glucose and fructose
CARBOHYDRATES Disaccharide: 2 sugars Ex. Glucose + fructose = sucrose Ex. Glucose + galactose=lactose Polysaccharide: many sugars Ex. Starch, grain, vegetables, glycogen, etc.
CARBOHYDRATES Short-term energy storage Converted to glucose quickly Glucose is used to make ATP (energy) Brain cells require glucose
PROTEINS Contains C, H, O, N Amino acids are the building blocks 20 different amino acids Amino acids contain an amine (NH 2 ) group and carboxyl group Amino acids aren t stored so a daily supply is required
Figure 2.16c
Figure 2.16ab
PROTEINS Used to make skin, hair, nails, muscles Hemoglobin Act as enzymes Catalyst Activation Energy Immune system functions Muscle contractions (actin and myosin) Part of cell membrane
PROTEINS Denaturation Increase Temperature Decrease ph
LIPIDS Contain C, H, O No 2:1 ratio of H:O Insoluble in water Ex. Fats, oils, cholesterol, triglycerides, phospholipids Glycerol and fatty acids are the building blocks.
LIPIDS Long term energy storage Insulates against heat loss Protective cushion for organs Cholesterol is part of the cell membrane structure
LIPIDS Saturated: single covalent bonds between carbon atoms Ex. Beef, port, whole milk, cheese, eggs Unsaturated: one or more double covalent bonds between carbons Ex. Olive oil, fish oil, sunflower oil
Figure 2.13
NUCLEIC ACIDS Composed of C, H, O, N, P Ex. DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) Nucleotides are the building blocks Nucleotides composed of nitrogen base, phosphate, and 5 carbon sugar
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