1.1 Biological Compounds Flashcards
What key elements are present as inorganic ions in living organisms? (M PINC)
magnesium ions (Mg²⁺)
iron ions (Fe²⁺)
calcium ions (Ca²⁺)
potassium ions (PO₄³⁻)
nitrate ions are also present
where do inorganic ions occur?
in the cytoplasm and body fluids of organisms for growth and development
What is the role of magnesium ions (Mg²⁺) in plants?
chlorophyll
what are phosphate ions (PO₄³⁻) required to make?
ADP and ATP
What is the role of iron ions (Fe²⁺) in animals?
They are a component of haemoglobin (oxygen carrying molecule to red blood cells)
what are nitrate ions required for?
to make DNA and Amino acids
What are calcium ions (Ca²⁻) needed to form?
calcium pectate for the middle of lamellae and to strengthen tissues e.g bones and teeth in animals and cell walls in plants.
how is water a polar molecule?
due to its uneven distribution of charge within the molecule.
(oxygen atoms attracts stronger electrons than hydrogen atoms. The unequal sharing of electrons means a negative charge is given to water when it’s near oxygen but positive when near hydrogen)
What is a metabolite?
molecule formed or used in metabolic reactions
describe the role of water as a metabolite.
water is a reactant in photosynthesis and hydrolysis reactions.
water is a product in aerobic respiration and condensation reactions.
Why is water’s high specific heat capacity important for organisms?
water acts as a temperature buffer, enabling endothermic to resist fluctuations in temperature to maintain optimum enzyme activity.
Why is water’s high latent heat of vaporisation important for organisms?
when water evaporates it has a cooling effect so there’s little water loss.
it’s important for homeostasis as organisms can lose heat through sweating or panting.
Why is water an important solvent for organisms?
it’s polar universal solvent (ability to dissolve in variety of substances) which enables chemical reactions to take place within cells, transport materials in plasma and removal of metabolic waste.
Why does water have a high surface tension?
due to the ordered arrangement and cohesion of molecules at the surface of the water.
Why is high surface tension of water important for organisms?
enables transport of water and nutrients through plant stems and small blood vessels in the body.
It allows small insects to ‘walk on water’ due to the supporting cohesion of the column of water
what is a monosaccharide and its general formula?
a monosaccharide is a simple sugar
general formula is Cn(H₂O)n
give some examples of monosaccharides.
Glyceraldehyde
Ribose
Deoxyribose
Fructose
Galactose
What is the name of the bond formed when two monosaccharides react?
Glycosidic bond
What is a disaccharide and its general formula?
molecule formed by the condensation of two monosaccharides, forming a glycosidic bond.
formulated C₁₂H₂₂O₁₁
Give some examples of disaccharides and their monosaccharide components.
Sucrose ( glucose and fructose)
Maltose (alpha glucose and alpha glucose)
Lactose (glucose and galactose)
What is a polysaccharide?
a polymer of monosaccharides, formed by many condensation reactions.
give 4 examples of polysaccharides.
starch
glycogen
cellulose
chitin
What is the function of starch?
energy storage in plants
Describe the structure of starch.
polymer of alpha glucose monomers
two forms: amylose and amylopectin
Amylose: unbranched chain joined by 1,4 glycosidic bonds
Amylopectin: branched chain joined by 1,4 and 1,6 glycosidic bonds
What is the function of glycogen?
energy storage in animals
How does the structure of glycogen relate to its function?
it’s highly branched enabling rapid hydrolysis of glucose molecules.
Describe the structure of cellulose.
Alternate glucose molecules rotated 180 degrees allowing hydrogen bonds between parallel chains, forming myofibrils.
consists of many beta glucose molecules joined by 1 beta and 4 glycosidic bonds.
Describe the function of cellulose.
linear polysaccharide that is the main component of the cell wall in plants so it provides structural support