Unit 2 Flashcards
Describe the work of Fredrich Wöhler
He had synthesised an organic molecule without the use of an organism. Disproving the theory of vitalism.
Why is carbon the basis of all living systems.
Carbon makes 4 strong covalent bonds with many other elements;[1 mark]
Carbon can bond to itself / make polymers;[1 mark]
C-to-C double (and triple) bonds can form / for unsaturated compounds;[1 mark]
Carbon produces stable compounds;[1 mark]
The tetrahedral shape of carbon’s compounds allows formation of different shapes;[1 mark]
Carbon can bond to many different functional groups eg. carboxylic acid SO its compounds can have many varied properties;[1 mark]
Similarities and differences between methane and water
Similarities:
Both are small molecules;
Containing a similar weight;
And are covalently bonded.
Differences:
Water is polar, methane is non-polar
Water contains covalent hydrogen bonds between molecules, methane does not.
Water is a liquid at room temperature due to its hydrogen bonding, methane is a gas at room temperature.
Describe why is glycogen a good short-term energy store? (2)
Has a highly branched structure creating many free ends (1), molecules of alpha-glucose can be easily hydrolysed off. (1)
Explain how LDL’s increase the risk for coronary heart disease. (4)
LDL’s transport cholesterol through the blood stream in the coronary arteries, sometimes these LDLs are deposited on the inner lining (1), this eventually hardens into a plaque (1). This plaque reduces the size of the lumen. (1) Eventually blocking the coronary arteries, causing coronary heart disease. (1) High levels of LDL’s also cause atherosclerosis.(1)
What is the proteome?
The totality of protein expressed in a cell, tissue or organism at a given time
Functions (with examples) of proteins
Enzymes (rubisco)
Transport (haemoglobin)
Associated with DNA (histones)
Membrane proteins (protein channels)
Hormones (testosterone)
Structural (collagen)
