miss palmer- biological molecules Flashcards
importance of calcium ions
needed for nerve impulse transmission and nerve contraction.
importance of sodium ions
needed for nerve impulse transmission and kidney function
importance of potassium ions
nertve impulse transmission and stomatal opening
importance of hydrogen ions
catalysis of reactions and ph determination
importance of ammonium ions
production of nitrate ions by bacteria
importance of nitrate ions
needed for nitrogen supply to plants for amino acid, protein formation
importance of hydrogen carbonate ions
needed for maintenance of blood ph
importance of chloride ions
balance positive charge of sodium and pottasium ions
importance of phosphate ions
cell membrane formation, nucleic acid ,bone formation
importance of hydroxide ions
needed for catalysis and PH determination
bonds of life rule ?
atoms with a greater share of electrons will be slightly negative compared with another atom in the bond that will be slightly positive.
what is a polar molecule and how is water one ?
polar: they have areas of negativity and positivity.
oxygen always has a greater share of electrons compared to hydrogen.
characteristics of water
high boiling point (100)
medium- takes a lot to increase temp.
ice less dense in water as hydrogen bonds fix into position slightly further apart - floats.
what does cohesive mean ?
moves as one mass because the molecules are attracted to each other.
what does adhesive mean ?
water molecules are attracted to other molecules.
what is water used for in life?
acts as solvent (liquid that dissolves solutes)
transports dissolved substances in and out of cell
a coolant , buffer temp change in cells- constant temp so enzymes work efficienlty but don’t denature.
how do hydrogen bonds form?
oxygen and hydrogen share electrons unequally when they bond. oxygen has greater share than hydrogen. they are attracted.
What elements is carbohydrates made of
Carbon, hydrogen, oxygen
Carbohydrate is a polymer but what are the monomers
Monosaccharides Glucose and ribose
What is glucose and what kind of sugar is it ?
A monosaccharide composed with 6 carbon atoms. Hexose sugar.
Properties of glucose
Polar molecule
Soluble in water because hydrogen bonds form between h20 and OH.
Bonds contain lots of energy.
What is a benefit of glucose being soluble?
Glucose dissolves so it can be used in cells. It dissolves in the cytosol of the cell which is an area of cytoplasm that’s not held by organelles .
What is the ribose
Pentose monosaccharide so made of 5 carbons.
Sugar part of RNA nucleotide.
What is the Benedict’s test for reducing sugars?
1.Place sample ( sucrose glucose ) in a boiling tube. Has to be in liquid from so may need blending.
2.add equal volume of Benedict’s reagent.
3. Heat mixture in a water bath for 5 mins.
Should turn brick-red if positive if not it will be blue
Benedict’s test for non-reducing sugars
Remains blue after heating- sucrose most common non- reducing sugar.
1. Heat non-reducing sugar with dilute HCL.
Non-reducing sugar has been hydrolysed(reacted with hydrogen ) by the acid.
Iodine test for starch
Add a few drops of iodine dissolved in potassium iodine solution.
Positive- changes from yellow/brown to purple/black.
Negative- remains yellow/brown
What is a reagent strip
Tests concentration of glucose. Colour gradient chart like a PH scale.
How are polysaccharides formed
Monosaccharides are joined together by glycosidic bonds
How does a condensation reaction work
During synthesis a hydrogen atom bonds to a hydroxyl group (OH) forming water.
How does hydrolysis reaction work
Break the glycosidic bond apart by addition of water
What is a disaccharide
Two monosaccharides together
What is starch and its properties
Main energy store in plants mixture of 2 polysaccharides amylose/amylopectin
Insoluble in water which is good for storage as water doesn’t enter by osmosis.