What is Life Made of?Everything is made up of atoms.
Living things are made up of cells.
Cells are made up of atoms.
Lecture 2: Bio-moleculesLecture 2: Bio-molecules
Bio-moleculesBio-molecules
1.1. Structure of WaterStructure of Water
1.1. Organic molecules Organic molecules الجزيئات العضويةالجزيئات العضوية Carbohydrates Carbohydrates الكربوهيدراتالكربوهيدرات LipidsLipids الدهونالدهون ProteinsProteins البروتيناتالبروتينات Nucleic acidsNucleic acids األحماض النوويةاألحماض النووية
Life exists on Earth because of the abundant Life exists on Earth because of the abundant liquid waterliquid water..
Water has been referred to as the Water has been referred to as the universal universal solventsolvent..
Aqueous solutions:Aqueous solutions: are solutions are solutions that have materials dissolved in water)that have materials dissolved in water)
So, it has slightly So, it has slightly positivepositive and a slightly and a slightly negativenegative sides sides..
II- Water- Water
Hydrophilic Hydrophilic محب للماءمحب للماء (Glucose)(Glucose):: Is any substance that has an affinity for waterIs any substance that has an affinity for waterتحب الماءتحب الماء ..
Hydrophobic Hydrophobic كاره للماءكاره للماء (Lipid)(Lipid):: Is the substances that have no affinity for water ال تح%ب الماءال تح%ب الماء . Because
they have non-ionic and non-polar covalent bonds.– Thus, water molecules cannot form hydrogen bonds with these
molecules. AmphipathicAmphipathic كاره ومحب% للماءكاره ومحب% للماء (Phospholipid)(Phospholipid):: Has end with affinity for water and the other end with no affinity Has end with affinity for water and the other end with no affinity
for waterfor water
The Hydrophobic molecules are the major ingredients of cell membranes.
Types of solutionsTypes of solutions
Organisms are sensitive to changes in pHOrganisms are sensitive to changes in pHThe acid:The acid: Is a substance that increasesincreases the hydrogen ion
(H+) concentration in a solution. When hydrochloric acid is added to water,
hydrogen ions dissociate تنفصل from chloride ions: HCl H+ + Cl-
Addition of an acid makes a solution more Addition of an acid makes a solution more acidic.acidic.
The base:The base: Is any substance that reducesreduces the hydrogen ion
concentration in a solution. Some bases reduce H+ directly by accepting
hydrogen ions. Other bases reduce H+ indirectly by releasing
OH- that combines with H+ to form water. NaOH → Na+ + OH- OH- + H+ →
H2O
Solutions with more OHOH-- than HH++ are basic solutions.
2. Biomolecules
1. Carbohydrates2. Lipids3. Proteins4. Nucleic Acids
4 main molecules 4 main molecules involved in lifeinvolved in life
(Carbohydrates, Lipids, Proteins and nucleic acids)
Mono-mer Di-mer Poly-mer
PolymerPolymer is a long molecule consists of a chain of is a long molecule consists of a chain of similar building molecules (similar building molecules (monomersmonomers) ) covalently bounded together.covalently bounded together.
Polymer can be broken down Polymer can be broken down إلى إلى يُـكَسـًـر to its to its يُـكَسـًـرmonomers by hydrolysis (adding Hmonomers by hydrolysis (adding H22O).O).
PolymerPolymer can be can be built upbuilt up يُـبْـنَىيُـبْـنَى by linking its by linking its monomersmonomers by dehydration (removing H by dehydration (removing H22O).O).
أحادى
ثنائى
عديد
Monomers
MacromoleculeCarbohydrates
Lipids
Proteins
Nucleic acids
MonomerMonosaccharide
(sugar)
Hydrocarbon chains
Amino acids
Nucleotides
Carbohydrates
Made of: carbon, hydrogen, and oxygen atoms
Job: provide living things with energy
Examples: sugars and starches (corn, rice, potato, bread)
Consisted of few Consisted of few hundredshundreds to few to few thousandsthousands of monosaccharides. of monosaccharides.
They are two types:They are two types:1- Storage1- Storage تخزينيةتخزينية. . Provide sugarProvide sugar for cell by hydrolysis for cell by hydrolysis ماء ماء إضافة . .إضافة
asas Starch ( Starch (in plantsin plants) ) النشاالنشا and and GlycogenGlycogen (in animals) الجليكوچ%ينالجليكوچ%ين
2- Structural 2- Structural تركيبية. . Serve as Serve as building materialsbuilding materials for the organism. for the organism.
as as Cellulose in Cellulose in plants (cell wall) and plants (cell wall) and Chitin Chitin الكيتينالكيتين in the in the
cuticle الُجـلَيد of insects
Polysaccharides Polysaccharides العديد العديد السكر السكر
Lipids
Made of: long chains of carbon and hydrogen atoms (with some oxygen).
Job: store energy, repel water
Examples: fats and oils (butter, cheese, oil)
•The Fatty acid components are saturated (there is no double bonds between The Fatty acid components are saturated (there is no double bonds between the carbons. All the carbons. All CC are linked with are linked with HH. .
•Thus, it is saturated with Thus, it is saturated with HH. .
•Most animal fats are saturated. Most animal fats are saturated. •They are solid at room temperature.They are solid at room temperature.
•* Saturated fats-rich diet results in * Saturated fats-rich diet results in AtherosclerosisAtherosclerosis الشريانى الشريانى التصلب ..التصلب
•These double bonds are formed by the removal of These double bonds are formed by the removal of H H atoms.atoms.
•Most vegetable fats (oils)Most vegetable fats (oils) and and fish fatsfish fats are unsaturated. are unsaturated.
* They are liquid at room temperature.* They are liquid at room temperature.
•They can be synthetically converted to saturated (solid) by adding They can be synthetically converted to saturated (solid) by adding HH ( (Hydrogenation Hydrogenation الَهدَْرچَـةالَهدَْرچَـة). ).
B)- Un-saturated FatsB)- Un-saturated Fats الدهونالدهون مشبعة مشبعة الغيرالغير
1313
PhospholipidsPhospholipids have two fatty acids attached to have two fatty acids attached to glycerol and a glycerol and a phosphate groupphosphate group at the third position. at the third position. The phosphate group carries a The phosphate group carries a negativenegative chargecharge.
PhospholipidsPhospholipids Are major components of cell membranesAre major components of cell membranes
• The fatty acid The fatty acid tailstails are are hydrophobichydrophobic, but the , but the phosphate group and phosphate group and its attachments form a its attachments form a
hydrophilichydrophilic headhead..
• Thus, it is Thus, it is amphipathicamphipathic
Proteins
Made of: Nitrogen, Carbon, Hydrogen, and other atoms
Job: Many different jobs in our bodies include include structural support, storage, transport of other structural support, storage, transport of other substances, intercellular signaling substances, intercellular signaling اإلشارات بين اإلشارات بين.movement, and defense against microbes., movement, and defense against microbes ,الخلويةالخلوية
Examples: enzymes, muscles, hair
Nucleic Acids
Made of: Phosphorous, Carbon, Nitrogen, Oxygen, and Hydrogen atoms
Job: Store genetic information
Examples: DNA, RNA