Biological Molecules Flashcards
What are the 4 key elements which make up biological molecules and are essential for all living organisms?
Hydrogen
Oxygen
Carbon
Nitrogen
What are Inorganic Ions?
Play and important part in living organisms
Occur in solution in the cytoplasm and body fluid of organisms in very low amounts.
What are Macronutrients?
Inorganic ions needed in small amounts.
What are examples of Macronutrients?
Inorganic ions such as- Magnesium, Iron, Phosphate and Calcium
What is the symbol for phospahte?
PO4 3-
What is magnesium’s importance?
Constituent for chlorophyll and so is essential for photosynthesis. Plants without it in the soil can’t make chlorophyll and so leaves are yellow (chlorosis)
What is magnesium required for?
Plant growth and development
What is iron’s importance?
A constituent of haemoglobin (which transports oxygen inside rbc’s)
A lack of this can lead to anaemia.
What is phosphate’s importance?
Used for making nucleic acids and is also a constituent of phospholipids, found in plasma membranes.
What are nucleic acids?
DNA, RNA, ATP
What is Calcium’s importance?
Structural component of bones and teeth in mammals and also a component of plant cell walls, providing strength
What does inorganic mean?
Compounds that don’t contain carbon bonded to hydrogen e.g. water, carbon dioxide and nitrogen gas
What are Micronutrients?
Inorganic nutrients needed in minute (trace) amounts e.g copper and zinc
What is a molecule?
Two or more atoms joined together(these atoms can be the same or different)
What is an organic compound?
Compounds that are based on carbon and contain carbon bonded to hydrogen e.g. carbohydrates, lipids and proteins
What can Carbohydrates and proteins form?
Very large polymers
What is polymerisation?
The linking of identical monomers to form larger molecules called polymers
What happens when 2 monomers link together and what is this reaction called?
Water is eliminated- condensation reaction
How can a condensation reaction be reversed?
By the chemical insertion of water to the polymer- hydrolysis reaction
What are carboHydrates?
Long chain units of sugar called saccharides.
What are the main functions of carbohydrates?
Storage and release of energy
Cellular Structures e.g. the cellulose walls of plant cells
What are monosaccharides?
small organic molecules (monomers) used as building blocks of complex carbohydrates
What are disaccharides?
two monosaccharides joined together by glycosidic bonds during a condensation reaction.
What’s are polysaccharides?
Large complex carbohydrates formed from very large numbers of monosaccharides joined together by glycosidic bonds.
What is the general formula for Monosaccharides?
Cn(H2O)n
What is a glyceraldehyde?
A triose used in metabolic reactions.
What is the most abundant monosaccharide?
Glucose
What is another feature of monosaccharides?
They have varying number of carbon atoms, for instance: ribose
What is ribose?
A pentose sugar ( a component of nucleic acid).
What is Glucose?
A monosaccharide containing 6 carbon atoms in each molecule, it has 2 isomers- alpha and beta glucose
Why is glucose of great importance?
It is the main substrate for respiration.
ABBA?
Alpha below, beta above
What are isomers?
Molecules with the same chemical formula (C6 H12 O6) but different arrangements of their atoms
What is the difference between Alpha and beta?
In alpha glucose the OH group in C1 points down and the H atom points up. In beta glucose the OH group on C1 points up and the H atom on C1 points down.
What are other examples of hexose monosaccharides?
Fructose and galactose.
Why are Fructose and Galactose isomers?
They have the chemical formula C6 H12 06 but have different arrangements of their atoms.
What are the features of glucose?
Small and therefore soluble in water
and easily transported in the bloodstream of animals phloem plants.
What are the functions of monosaccharides?
Source of energy in respiration
Building blocks for larger molecules
Intermediates in reactions
Constituent of nucleotides
What are the three classes of carbohydrates?
Monosaccharides
Disaccharides
Polysaccharides
What are examples of monosaccharides?
glucose
Fructose
Galactose
Glyceraldehyde triose sugar
What are some other types of monosaccharides of biological importance?
Pentose sugars(e.g. deoxyribose sugar found in DNA nucleotides) and triose sugars that are intermediates in respiration and photosynthesis
what are the properties of monosaccharides?
small so all soluble in water and therefore can easily dissolve inside the cell and they are easily transported in the blood stream of animals
What are the names of the disaccharides?
Either alpha or beta
What is the general formula for disaccharides?
C12 H22 O11
how are disaccharides formed?
When 2 hexose sugars is combine into condensation reaction (where a new glycosidic bond is formed with the elimination of water)
What are examples of disaccharides?
maltose- a + b glucose
Sucrose (alpha)- glucose +fructose
Lactose (beta)- glucose + galactose
What is maltose?
Found in seeds and is an important source of glucose during germination
what is sucrose?
transported through the phloem of all plants
What is lactose?
It is found in mammalian milk and is an important source of energy for their young
What is hydrolysis reaction used to do?
break down disaccharides into their respective monomers
what is the general formula of maltose, sucrose, lactose?
CH2 OH
why is the bond between the two sugars called a 1-4 glycosidic bond?
The bond is between carbon 1 of one monosaccharide and carbon 4 of the second monosaccharide
how are polysaccharides formed?
The monomers, which are monosaccharides (such as glucose) are linked together, by glycosidic bonds formed by a series of condensation reactions
what is the smallest polysaccharide made up of?
three Monosaccharide monomers are linked together
Why are polysaccharides insoluble?
They are usually made up of thousands of monomers, which gives them a large size
What are the two types of functions that polysaccharides usually have?
structural, or storage
what is glucose’s function in the body?
glucose id the main source of energy in cells and must be stored in an appropriate form
why is glucose converted into a storage polysaccharide like starch and glycogen?
glucose is soluble in water, and this would affect osmosis within the cell
What are shared functions of starch and glycogen?
-Insoluble, so don’t affect
-Compact so can be stored in a small place in the cell
-Easily hydrolysed to release to glucose for respiration
What are examples of polysaccharides?
starch
Glycogen
Cellulose
chitin
what is starch?
 Glucose energy storage polysaccharide in plant cells made up of two different molecules- amylopectin and amylose.
What is the starch polymer made up of?
Thousands of Alpha glucose monomers
what is the structure of amylose?
straight chained, helical polymer, containing alpha 1-4 glycosidic bonds
why can amylose store a lot of energy?
it is coiled, so it is a very compact molecule
What is the structure of amylopectin?
Branched polymer containing alpha 1-4 and alpha 1-6 glycosidic bonds
how is energy released quickly by amylopectin?
It is rapidly digested by enzymes due to presence of many side branches
what is glycogen?
an animal, glucose energy storage polysaccharide found inside liver and muscle cells made up of many alpha glucose molecules
Why is glycogen being highly branched important?
this allows the quick release of glucose(energy) from the end of the branches to be used in respiration
what type of bonds does glycogen have?
1-4 and 1-6 glycosidic bonds
what does glycogen being large but compact mean?
maximises the amount of energy it can store
what is the most abundant organic molecule on Earth?
Cellulose
what is cellulose?
 A polysaccharide made up of beta glucose monomers
why is cellulose important in plants?
it is important as a structural carbohydrate, and it is the most important component in the plant cell wall
what is the structure of Cellulose?
consists of long, parallel chains of beta glucose molecules joined by 1-4 glycosidic bonds