Biology Flashcards
Topic #2
What are enzymes? Their function?
Enzymes are protein made up of monomers called amino acid. They are biological catalyst that speed up the rate of cellular reactions, but are not change by the process.
What will happen if we did not have enzymes?
Without enzymes reactions are too slow to cure that the cells would die from not being able to do key life processes
What happen if the temp gets to high for enzymes?
When they reach a high enough temperature, they will lose their shape and breakdown. Just as known as denaturation. the enzyme is then unable to function as the active site is the wrong shape for the substrate.
What happen to enzymes in PH
The Ph level causes the enzymes active site to become denatured and the active site loses its important shape.
Enzyme action
An enzyme usually only act on single specific reacting a.k.a. the substrate. They have a pocket or groove structure called the active site, its shape is complementary of the substrate. The enzymes can’t be consumed or altered.
Define osmosis
Osmosis is the movement of water molecules from an area of high water potential to a area of lower water potential through a partially permeable membrane.
What are solutes?
Solutes are substances that can be dissolved in a solvent (usually water)
Solute + solvent = solution
Osmosis - turgor pressure
Turgor pressure is the force within the cell that pushes the cell membrane against the cell wall. Turgor pressure is important so that plants stay upright and have exposure to sunlight.
Define hypertonic
A hypertonic solution is one that has a higher solute concentration than the cell.
Define hypotonic
A hypotonic solution is one that has a lower solute concentration than the cell
Define isotonic
An isotonic solution has a equal concentration of solutes inside and outside the cell.
Plants cell in a hypertonic solution
When a plant cell is placed in a hypertonic solution, there is a movement of water out of the south, causing a reduction in turgor pressure and the cell membrane to peel back from the shower wall. This is known as the cell becoming plasmolysed.
Plant cell in hypotonic solution
If a cell is placed in a hypotonic solution, there is a movement of water into the cell, causing an increase in turgor pressure and a cell to become turgid. The cell membrane pushes against the cell wall.
Plant cells in an isotonic solution
If a cell is placed an isotonic solution, there is no movement of water, causing the cell to stay the same.
What is glucose? Their function?
A glucose molecule is made from carbon, hydrogen and oxygen. The glucose function is to produce energy from respiration. Plants transport sucrose, which is then converted into glucose and use for respiration.
What are the tree functions of glucose? Their function?
All of these are made from chains of glucose
* cellulose - plants used to make cell walls
* starch - plants used to store energy
* glycogen - animals, use to store, energy in liver
Testing for reducing sugar
We can test for reducing sugars using Benedict solution
When it is heated, it turns:
Blue - green - yellow - orange - red
Testing for starch
We can test for starch by using iodine
It turns orange/brown - blue/black
What is the fat structure?
Contains carbon hydrogen oxygen
Three Fatty acid chains joint to one.glycerol molecule
Detail of fats
Solid fats room temperature contain situated fats and liquid fat known as oils contain unsaturated fats.
Function of fats
Energy dense molecule, factor under skin is adipose tissue that insulates the body, used to produce cell membranes and some hormones, plants store oil in their seeds
Testing for fats
The ethanol emulsion test. If fat is present the solution will turn cloudy.
Structure of proteins
Proteins are made of long chains of amino acid molecules and they are made from hydrogen nitrogen oxygen, carbon and sometimes Sulfur.
Function of amino acid?
Used to make new proteins and enzymes
Used for growth and repair cells
Used to make antibodies which are used to kill bacteria and viruses
Testing for proteins
The biuret test. If protein is present it turns
blue - purple
Define active transport
The movement of particles through a cell membrane from a region of lower concentration to a region of high concentration, using energy from respiration. Uses ATP as an energy source and requires a carrier protein in the cell membrane.
Active transport in root hair cell
Plants need ions to survive e.g nitrate, potassium, magnesium, sodium, phosphates. Ions are in a lower concentration in the soil. Then they are in the root hair cells therefore, for the plant to get enough ions they are forced to use active transport to uptake more ions
Define diffusion
Diffusion is the net movement of particles from our region of high concentration. Region of low concentration requiring no energy at all. (Passive transport)
Which states are particles able to diffuse
Molecules in liquid and gases are constantly moving randomly and bumping into each other. This means that they tend to spread. In solids, the particle cannot move so diffusion does not occur.
Factors that affect rate of diffusion - concentraction gradient
The difference in concentration between two areas is called a concentration gradient
Larger concentration gradient faster diffusion.
Factors that affect rate of diffusion - temp
Temperature, more energy associated with the particle at high temperature means faster rate of diffusion
Factors that affect the rate of diffusion - suface area
The larger the surface area in contact between the two regions, the faster rate of diffusion
Factors that affect the rate of diffusion - distance
Distance the largest distance, the long time to diffuse
Plasma membrane
Plasma membranes around cells/organelles, are semi permeable, meaning they allow some substances through, but not others
Why is the diffusion important?
All living cells rely on the fusion to live they use it for:
* getting warm materials for respiration of photosynthesis
* removing waste product
* importing, or exporting products like protein
