Biochemistry Flashcards
Briefly explain the structure of a water molecule
It is made up of 2 hydrogen atoms covalently bonded to one oxygen atom.
In relation to the molecular structure of water, what is a dipole?
There is an unequal distribution of charge within the molecule; different parts of the water molecule have uneven charges (oxygen has a small negative charge and hydrogen has a small positive charge)
Water’s peak density is at 4 degrees celcius, state why this is beneficial to organisms
Water freezes at the surface, forming a layer of ice with liquid water underneath. When water gets colder than 4 degrees celsius, it becomes less dense than the warmer water below it and so it stays on the surface where it forms ice. The layer of ice insulates water below it from further temperature changes, this water stays liquid and provides an environment in which organisms can continue to survive
State how a high specific heat capacity of water impacts living organisms
A high specific heat capacity means that large changes in temperature of external environments have relatively small effects on the temperature of the body and for aquatic organisms a high specific heat capacity means that the temperature of the external environment remains relatively stable
State how high latent heat of vaporization impacts living organisms
When liquid sweat lies on the surface of the skin, the water in the sweat absorbs heat energy from the body as it evaporates. Making the ability to sweat a useful cooling mechanism. It also helps to cool plant leaves in hot climates
Explain how a high latent heat of fusion impacts living organisms
A high latent heat of fusion makes it quite difficult to freeze water, so it tends to stay a liquid and since cytoplasm contains alot of water the high latent heat of fusion reduces the likelihood of ice crystals forming inside cells.
Water is a great solvent, how does this benefit organisms
Many reactions like metabolic reactions that makes life possible will only take place in solution, Also water can flow and as such it can carry dissolvd substances from one place to another which happens in the blood and in the xylem tissue
Water is relatively dense, how does this impact organsims
Most living organisms, containing alot of water have density which is quite close to that of water which makes it easy for them to swim.
Water has high cohesion, how does this impact living organisms
Cohesion makes it easy for water to move by mass flow, that is, a large body of water can flow in the same direction without breaking apart, this is important for the flow of blood in animals and the flow of water within xylem vessels in plants
What is the function of glucose
it is an important source of energy and provides nutrients to your body’s organs, muscles and nervous system
Revise ring structure of glucose
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What is the function of sucrose
it provides your body with the energy required to perform physical and mental functions. and it is the main form in which carbohydrates are transported in plants
Revise the ring structure of the sucrose
it is made up of an alpha glucose molecule linked to a beta fructose molecule by a 1 - 2 glycosidic bond
Explain how starch benefits living organisms
They are stored in organells called plastids, it is a mix of amylose and amylopectin and is how plants store the carbohydrates they make in photosynthesis
Explain glycogen
It is an insoluble and unreactive energy reserve in animal cells linked through alpha 1-4 glycosidic bonds with alpha 1-6 branches
