biology form 4: water
DESCRIPTION
This slide is about chemical composition in cell. It shows the properties and functions of waterTRANSCRIPT
What do you see?
What do the plant need for their growth?
Theme : Theme : Investigating the Cell as a Investigating the Cell as a Basic Unit of Living ThingsBasic Unit of Living Things
Learning Area:Learning Area:
Chemical Composition of the CellChemical Composition of the Cell
Learning outcomesLearning outcomes
Student is able toStudent is able toState the element in the cellState the element in the cellList the chemical compound in the cellList the chemical compound in the cellExplain the important of organic Explain the important of organic
compound in cellcompound in cellExplain the important of the water in the Explain the important of the water in the
cellcell
Most common elementMost common element
1.1. CarbonCarbon2.2. OxygenOxygen3.3. HydrogenHydrogen4.4. NitrogenNitrogen
96% of the mass of body96% of the mass of body
CaCan n nitnita a oobserve bserve hydrhydraa
Other elementOther element
1.1. CalciumCalcium2.2. PotassiumPotassium3.3. PhosphorusPhosphorus4.4. SulphurSulphur5.5. SodiumSodium6.6. ChlorineChlorine7.7. MagnesiumMagnesium8.8. FerumFerum
SoSofi fi cacarry rry phophoto to magmaggi gi chlorinechlorine ffor or popolice lice sulsuluu
2 major groups2 major groups
Chemical compounds in the Cell
Organic
compounds
Inorganic
compounds
•ORGANIC COMPOUND – chemical compound that contain the element of
carbon & hydrogen•INORGANIC COMPOUND – constitute
non-living matter and do not contain carbon.
INORGANIC COMPOUNDORGANIC COMPOUND
The important of organic compoundThe important of organic compound
Amino acid- building block of proteinAmino acid- building block of proteinCarbohydrate- major source of energyCarbohydrate- major source of energyLipids- not soluble in waterLipids- not soluble in water
Nucleic AcidNucleic Acid
• Contains:Contains:
Nucleic Acids
HydrogenHydrogen Carbon Carbon NitrogenNitrogen OxygenOxygen PhosphatePhosphate
• Basic unit structure:
Nucleotide
• 2 types of nucleic acid:
Nucleic Acids
DNA (Deoxyribonucleic acid)
RNA (Ribonucleic acid)
DEOXYRIBONUCLEIC ACIDS (DNA)
It is double stranded polynucleotide. 2 strands 2 strands twisted around each other. around each other. It will form It will form double helix (Watson and Crick) Can be found in nucleus.. Also can be found in chloroplast and
mitochondria.. Contain genetics information that can inherited
from parents to offspring.
RIBONUCLEIC ACID (RNA)RIBONUCLEIC ACID (RNA)
Found in cytoplasm, ribosome and and nucleus.
Copies information carries by DNA for use in protein synthesis (act as messenger)
It is also genetics material in virus.
Phosphate group
Pentose sugar
Nitrogenous base
The structure of a nucleotide Structure of DNA
Most important inorganic chemical compound.
Makes up 70% of our body.70 – 90% weight of cell It is important because its chemical
properties and physical properties.Present in cell, lymph, blood plasma and
interstitial fluid.
The importance of water in the cell
1) Polar molecule- Means : molecule with an equal
distribution of charge.- Have +ve charge end & -ve charge end.- It attract one another.- Considered as solvent of life (universal
solvent) - Can dissolve many ionic compound eg,
salt, sugar
Function of water
Structure of water molecule
2) Transport medium- Transport medium in blood, lymphatic,
excretory and digestive system and in vascular tissues of plants.
- Blood plasma made of 90% water.- Water dissolve the sugar, amino acids,
and gases. - All this substances will transport to all
parts of the body.- Waste product excreted from body
trough urine.
3) Medium for biochemical reactions- Can occur if there is water- Example; water use for breaking downs
protein, lipids and sugars in food.
4) Maintenance stable internal environment- Concentration water & inorganic salt important
maintain osmotic balance.- For activities & life process in cell.- Importance in maintaining body temperature.- Eg; excess heat through perspiration, urination
and defecation.
5) Lubrications- Assist movement of food substances in Assist movement of food substances in
interstitial tractinterstitial tract (Mucus).- Lubricates the joints to ease the Lubricates the joints to ease the
movement at the jointsmovement at the joints (Synovial fluid)
6) High cohesion- Water molecule tend to stick to each Water molecule tend to stick to each
other.other.- Move along unbroken column through Move along unbroken column through
vascular tissue in plant.vascular tissue in plant.
7) Support- Gives support the plant cells (Gives support the plant cells (non-woody plant
– – turgidity))- Lack of water causes a plant to Lack of water causes a plant to wilt..
8) Buffer- Water is crucial in maintaining the pH of the Water is crucial in maintaining the pH of the
internal environment of the cell.internal environment of the cell.- Substances called Substances called buffer that dissolves in that dissolves in
water are able to mop up excess acid or water are able to mop up excess acid or bases.bases.
9) Cooling agent- Evaporation of water cools down the plant cell
Concept Map
Organic Compound Chemical compounds
in the cell
WaterNucleic Acid
DNA RNATransport medium
Polar molecule
Medium
Biochemical reaction
Lubrication
Support
High Cohesion
Buffer
Cooling Agent
Maintenance stable
internal environment
Compare and contrast these groups of food
Classes of carbohydrate
• simplest sugar
• represent aldehydes or ketones of from 3-6 carbons in length.
• Glucose "blood sugar"
• Fructose "fruit sugar"
• Galactose the breakdown of lactose.
1. monosaccharide
D-glucose
(ring structure)
glucose
Classes of carbohydrate
2. disaccharide
• made by connecting two simpler molecules.
•the removal of water from between the two molecules
condensation
Glucose + glucose Maltose + water
condensation
hydrolysisdisaccharide
Formation of sucrose ( cane sugar)Formation of sucrose ( cane sugar)
Glucose + fructose sucrose + watercondensation
hydrolysis
disaccharide
Glucose + galactose lactose + watercondensation
hydrolysisdisaccharide
Formation of lactose ( milk sugar)
Remember !!!! Only maltose and lactose are reducing sugar while sucrose is non-reducing sugar
polysaccharidespolysaccharides
Hundred monomerHundred monomer combine through the combine through the condensationcondensation to to form form long chainlong chain of molecules of molecules
Insoluble in waterInsoluble in water Do not taste sweetDo not taste sweet Example: starch, glycogen, cellulose and chitinExample: starch, glycogen, cellulose and chitin
Glycogen• branching is more numerous• stored in the liver and muscle tissue of our bodies• Found in animal
Starch - found in plantStarch - found in plant
- main carbohydrate reserve- main carbohydrate reserve
Cellulose – found in plantCellulose – found in plant
- make up cell wall- make up cell wall
Chitin - Chitin - structural component same structure with cellulose
Amino acids, peptides and protein
• A.a. contains :
1. amino group
2. carboxylic acid group
3. side chain gp/R group
Amino acids are linked together by peptide bonds
Polypeptides : peptides ( up to 50 a.a)
protein (longer)
Fatty acids and lipids
• Contain :
1. one carboxylic acid
2. with long HC chain
•Are monocarboxylic acids
• Usually contain even number of C atoms
• water insoluble
• E storage
Alkyl gp
Contains
C & H atoms
Carboxyl gpRCH2 C
O
OH
•unsaturated f.a. = contain double bond
•Saturated f.a = only single bond (saturated with hydrogens!)
•
Fatty acids are combined with one glycerol to form a fat
molecule triglycerol
Through a process :esterification/dehydration/condensation