B4 - The Processes of Life Flashcards Preview

GCSE OCR Biology > B4 - The Processes of Life > Flashcards

Flashcards in B4 - The Processes of Life Deck (26):

What is the symbol equation for Aerobic Respiration?

C6H12O6 + 6O2 --> 6CO2+6H20+38ATP.


What is the symbol equation for Anaerobic Respiration?

C6H12O6 --> C3H6O3 (Lactic acid) + 2ATP


What is the symbol equation for photosynthesis?


Hint: It's the opposite of Aerobic Respiration - minus the ATP!

6CO2 + 6H2O --> (Light energy/Chlorophyll) --> C6H12O6 + 6O2.


What are some of the effects of lactic acid?

  • Muscle aches.
  • Cramp.
  • Rapid breathing.
  • Stomach pain.


What organelles do both animal and plant cells have?

  • Nucleus.
  • Cytoplasm.
  • Cell membrane.
  • Mitochondria.
  • Ribosomes.


What additional organelles do plant cells have?

  • Cell wall.
  • Chloroplasts.
  • Permanent vacuole.


What is the job of the Nucleus?

The Nucleus holds genetic information, called DNA. Allows genetic transcription to take place.


What is the job of the Cytoplasm?

The Cytoplasm is where chemical processes controlled by enzymes take place. This includes anaerobic respiration.


What is the job of the Cell membrane?

The cell membrane controls the movement of substances in/out of a cell.


What is the job of the Mitochondria?

The Mitochrondria is where most energy is released from respiration.


What is the job of the Ribosomes?

The Ribosomes deal with Protein synthesis.


What is the job of the Cell wall?

The Cell Wall strengthens the cell.


What is the job of the Chloroplasts?

The Chloroplasts contain chlorophyll (A green pigment) which absorbs light energy for photosynthesis.


What is the job of the Permanent vacuole?

The permanent vacuole is filled with cell sap to keep the cell enlarged with water. It is like a sack.


How can Anaerobic Respiration be useful?

  • It provides a little more energy to cells when very necessary, e.g: when running away from danger.
  • In sewage farms, anaerobic microbes can be added to the solid matter. These break down the sewage and release methane gas, which is collected as a biogas.
  • Anaerobic respiration is used in yeast when baking. Yeast in bread dough releases CO2, which makes the dough rise before baking.
  • Anaerobic respiration is also used in yeast for brewing to produce alcohol (ethanol). The process is known as fermentation. If oxygen gets in, the yeast stops respiring anaerobically, and the alcohol turns to vinegar (ethanoic acid).



What is Diffusion?

The overall movement of substances from regions of high concentration, to regions of low concentration.

e.g: O2, CO2 and dissolved food.


What is Active Transport?

The movement of substances from an area of low concentration to an area of high concentration.



What is Osmosis?

Osmosis is a type of diffusion, and is the movement of water from a high concentration to a low concentration.

Water passes through the cell membrane, which allows the passage of water molecules, but not solute molcules (They're too big).


Why is it important that the concentration of urea is kept very low?

Because it allows diffusion, keeps concentration gradient between blood and fluid and low concentration prevents urea moving from fluid back to blood.


How do you irreversibly change the shape of the active site of an enzyme?

  • Heating the enzyme above a certain temperature.
  • Altering the pH level.


What is cellulose?

A long polymer chain of glucose.


What is starch?

A long chain of identical sugar molecules.


How are proteins formed from glucose and nitrates?

  1. The glucose and nitrates join together to make larger molecules of amino acids.
  2. Amino acids are joined together to make proteins (Polymers of amino acids).


How are proteins formed?

By creating amino acids through:


C6H12O6 (Glucose) + NO3- (Nitrate) --> Amino Acid (AA).


Proteins are polymers of Amino Acids.


Explain how plants get their energy.

Plants need to absorb nitrates from the soil for healthy growth.


They normally absorb nutrients through diffusion, however the concentration of nitrates outside the plant is lower than that inside the plant, therefore the plant must use active transport to retain the nitrates.


The energy required for active transport comes from respiration.


Explain how to conduct an experiment on how light affects plants.

Use a quadrat across a transect line and go up in intervals (e.g: 20 metres). Record the light intensity with a light meter at each result, and measure the number of different types of plants by eye and by using an identification key. Finally, see if there is a trend.


Note that using a quadrat is representive of the entire area but also random to avoid bias.