Biological Molecules Flashcards
All cells are made up of a wide range of elements and compounds. The majority of the cell mass is made up of water and four groups of molecules, known as the biological molecules. What are they?
Biological molecules are carbohydrates proteins lipids (fats) and DNA, our genetic material
What are carbohydrates, proteins and lipids all made up of ?
Carbon (C), hydrogen (H) and oxygen (O). Proteins also contain nitrogen (N)
When we say that a molecule is an organic molecule, what does it contain?
A molecule that contains carbon is an organic molecule
What are carbohydrates composed?
Carbohydrates are composed of carbon, hydrogen and oxygen
What are the two types of carbohydrates?
The two types of carbohydrates are simple sugars and complex carbohydrates
What is soluble in water and sweet tasting?
Sugar is soluble in water and sweet tasting
What do we call single units of sugar and what do we call two molecules of sugar joined together?
Single units of sugar are called monosaccharides Two molecules joined together are called disaccharides
What type of carbohydrate is made of thousands of glucose molecules?
Complex carbohydrates are made of thousands of glucose modules
How are carbohydrates stored in animals, plants and plant cell walls?
Carbohydrates are stored as glycogen in animals, starch in plants, and cellulose in plant cell walls
What are proteins composed of? Four things.
Proteins are composed of carbon hydrogen oxygen and nitrogen
What are made up of many amino acid’s which are joined together? There are 20 different amino acids joined together in different combinations. This makes almost unlimited number of types this thing.
Proteins
Proteins have many functions or jobs. What types of molecules are collagen and keratin?
structural molecules
Proteins have many functions for jobs. What type of proteins controlled chemical reactions?
Enzymes
Proteins have many functions for jobs. What type of proteins are messenger molecules?
Hormones
What is the name of the type of proteins that combat disease?
antibodies
Proteins have many functions or jobs. What types of proteins help with transport around the body?
Haemoglobin and cell membrane proteins will help transport
Fats and oils are both types of what?
Lipids
What are lipids composed of?
Lipids are composed of carbon hydrogen and oxygen
What are 5 functions of lipids?
Energy storage
Thermal and electrical installation
Protection of organs
Making some hormones
And are an essential part of cell membranes
Lipids are all made up of two types of molecules, what are they?
Glycerol and fatty acids
What are the two types of fatty acids?
Saturated fatty acids, which are solid at room temperature
Unsaturated acids, or oils, which are liquid at room temperature.
What is Benedict’s test for glucose?
Add 5 cm³ of benedicts solution to the liquid, then heat using a water bath at 60°C. If glucose is present, you will see a colour change from blue to brick red
Fill in the blanks:
Add 5 cm³ of ______ solution to the liquid, then heat using a water bath at 60°C. If ______ is present, you will see a colour change from blue to brick red
Benedict’s and glucose
What is the iodine test for starch?
Add 2 to 5 drops of iodine solution, and if starch is present you will observe a colour change from brown to blue black
Fill in the blanks:
Add 2 to 5 drops of ______ solution, and if ______ is present you will observe a colour change from brown to blue black
Iodine and starch
What is the Biuret Reagent test for proteins?
The Biuret Regent test for proteins is Add 2 to 5 drops of Biuret Regent If protein is present you will observe a colour change from pale pink to purple
What is this test called and what is it testing for?
Add 2 to 5 drops of ______ regent, and if ______ are present you will observe a colour change from pale pink to purple
Biuret and proteins
What is the emulsion test for lipids?
the emulsion test for lipids is: Add 2 cm³ of ethanol to the substance Add the solution to a boiling tube of water If lipids are present a white ( milk like) emulsion will Form
What is this test called and what is it testing for? Add 2 cm³ of ethanol to the substance Add the solution to a boiling tube of water If lipids are present a white ( milk like) emulsion will Form
the emulsion test for lipids?
All the chemical reactions which occur in cells are controlled by a group of proteins. These are biological catalysts. What are they called?
Enzymes
What do we call a chemical which increases the rate of reaction without being used up itself in the reaction?
A catalyst
What is a catalyst?
A catalyst is a chemical which increases the rate of reaction without being used up itself in the reaction
What are the three steps that explain the way that The activities of a cell are controlled?
1) The nucleus contains genes 2) The genes control the production of enzymes 3) The enzymes catalyse the reactions in the cytoplasm. Everything which a cell does depends on which genes in its nucleus are working
What do we call the substance or substances that the enzyme acts on?
Substrate
What do we call substance for substances produced by the reaction?
Product
What two types of reactions catalysed by enzymes have an increased rate?
Catabolic reactions, breaking down large molecules into smaller products, e.g. digestion Anabolic reactions, building large molecules from smaller substrates, e.g. DNA synthesis Enzymes can also function both intra cellular and extra cellular environments
Do Enzymes function in intracellular for extracellular environments?
Both
The shape of the enzyme is vital. The substrate fits the active site rather like what? What is the name of the theory
Lock and key theory
What does the substrate bind to for a reaction?
The substrate binds to the active site
For an enzyme which part has a specific shape which is complimentary to the shape of the substrate?
Active site
When the substrate binds to the active site of the enzyme, a reaction can occur using less of what?
Less energy is needed for a reaction to occur , a lower activation energy. Without enzymes reactions would occur too slowly and organisms would die
What do we call the type of energy that means that molecules are constantly moving around and colliding with each other ?
Kinetic energy
For reactions with enzymes what happens when the temperature increases?
As temperature increases molecules have more energy. They move faster, more kinetic energy. If molecules are moving more quickly, they are more likely to collide with other molecules or with enzymes, collision theory. Normally a rise in temperature of 10° C makes the reaction work twice as fast
What do we call the temperature when an enzyme will work at its fastest?
Optimum temperature
What temperature will an enzyme becomes denatured?
High temperatures
What happens to the enzyme when it becomes denatured at high temperatures.?.
The thermal energy alters the bonds holding the protein in its specific 3-D shape. The shape of the active site will change. As a result the active site will no longer be complimentary to the shape of the substrate molecule. The substrate cannot bind to the active straight and the reaction cannot occur. We say that the enzymes have been denatured
What do we call the best pH for an enzyme to cause reactions?
optimum ph Most enzymes have an optimum pH of around seven.
Pepsin has an unusual optimum pH what is it
Pepsin has an unusual optimum pH pepsin has an optimum pH of two. Pepsin is therefore specialised to work best in acidic conditions
What happens to an enzyme in an extreme pH? What happens when it is too acidic or too alkaline?
Denatured
What does the size of the surface area mean for the way that enzymes will catalyse reactions?
Enzymes will catalyse reactions more rapidly if the substrate has a larger surface area. This is because there is more of a substrate accessible to the enzyme and so more chance of a successful collision between substrate and an active site.
What does Bile do in the small intestine?
In the small intestine bile emulsifies, breaks down, fat droplets. This increases the surface area and so increases the rate of fat digestion by lipases
How does the concentration of substrate and enzymes affect the enzyme controlled reactions?
Enzyme controlled reaction will occur more rapidly if the concentration, amount in a given volume, of the substrate and/or the enzyme is increased. This is because there are more enzyme and substrate molecules and so there is more likely to be a successful collision between the substrate and active site.
Label the diagram
Fill in the table
What happens to fat when in the small intestine and bile is produced?
