B4 - The Processes Of Life Flashcards
What are DNA?
They contain genetic codes
What do all cells contain?
DNA and organelles
What are organelles?
Parts of the cells structure that allows the cell to preform specific functions
What parts do animals have in them?
Cytoplasm, mitochondria, a nucleus and a cell membrane
What is the cytoplasm?
Where chemical reactions take place (anaerobic respiration)
What is the mitochondria?
Contains the enzymes needed for aerobic respiration
What is the nucleus?
Contains the DNA and controls the cell
What is the cell membrane?
Something that allows chemicals like gases and water to pass through
What parts do plant cells have?
Cell wall, vacuole, cytoplasm, cell membrane, chloroplast, mitochondrion and nucleus
What is the cell wall?
Strengthens the cell by being made of cellulose
What is the vacuole?
Helps support the cell
What are the chloroplasts?
Contains chlorophyll which absorbs light energy and also contains some enzymes needed for photosynthesis
What are enzymes?
Protein molecules that speed up the rate of chemical reactions in cells
What do enzymes need to work at the optimum?
A specific temperature
What happens after the optimum enzyme activity is reached?
The active site is damaged and starts to slow down, eventually it stops working and therefore is denatured
What does the lock and key model explain?
How only a molecule with the correct shape can fit into an enzyme
What is the active site?
The place where the molecule fits into the enzyme
How can the active site be changed?
Heating the enzyme above a certain temperature and altering the pH level
What is respiration?
The release of energy from food chemicals in all living cells
What are the two types of respiration?
Aerobic and anaerobic
What is aerobic respiration?
Respiration using oxygen; releases energy and produces carbon dioxide and water
What is the word equation for aerobic respiration?
Glucose + Oxygen = Carbon dioxide + Water + Energy released
What is the symbol equation for aerobic respiration?
C6H12O6 + 6O2 → 6CO2 + 6H2O
Where does aerobic respiration occur?
In animal cells, plant cells and microbial cells
What is the energy released in aerobic respiration used for?
Movement and active transport
What is anaerobic respiration?
The process of releasing energy from glucose in living cells without oxygen to produce a small amount of energy quickly
What is the word equation for anaerobic respiration in plant cells
Glucose = Carbon dioxide + Ethanol + Energy released
What’s the difference between the word equation for anaerobic respiration in plant cells and animals cells?
Lactic acid replaced Carbon dioxide + Ethanol
What is the word equation for anaerobic respiration in animal cells?
Glucose = Lactic acid + Energy released
Give examples of when anaerobic respiration occurs?
When no or little oxygen is present so when plant root cell are waterlogged, vigorous exercise (100m)
Why is aerobic respiration more efficient than anaerobic respiration?
Because it released much more energy per glucose molecule
What is photosynthesis?
The chemical process that takes place in green plants to produce glucose
What is the word equation for photosynthesis?
Carbon dioxide + Water = Glucose + Oxygen
What is the symbol equation for photosynthesis?
6CO2 + 6H2O = C6 H12 O6 + 6O2
What is a polymer?
A long chain molecule made from copies of the same thing (example glucose)
What are the limiting factors for photosynthesis?
Temperature, Carbon dioxide concentration and Light intensity
What is a quadrat?
Anything within a defined area
What is a transect?
A random section across an area
What is diffusion?
The overall movement of substances from regions of high concentration to low concentration
What substances move in and out of cells by diffusion?
Oxygen, Carbon dioxide and Dissolved food
How are nitrates from the soil absorbed by plants?
Active transport
Why does a plant use active transport to get nitrates from the soil and not diffusion?
Because nitrates outside the plant has lower concentrations than inside it so energy from respiration is needed to absorb them by active transport
What is active transport?
The movement of a substance against a concentration gradient (regions of low concentration to high) requiring energy from respiration
What is osmosis?
A type of diffusion but in water from a dilute solution to a concentrated dilution through a partially permeable membrane
