Unit 1 Flashcards
What happens in the first stage of photosynthesis?
Light energy is trapped by chlorophyll. Water is broken down into oxygen, energy and hydrogen
What happens in stage two of photosynthesis?
NADP carries the hydrogen into the carbon fixation stage. Hydrogen reacts with carbon dioxide to form glucose
Where does stage two of photosynthesis take place?
In the stroma
What is the name of stage two of photosynthesis?
The Calvin cycle / carbon fixation
What substance is needed to drive stage two of photosynthesis?
ATP
What does the granum contain?
The pigments molecules/ chlorophyll
What can glucose be used for?
Starch, cellulose, proteins, converted into fats and oils
What are the limiting factors of photosynthesis?
Temperature, light intensity, CO2 concentration
What is the word equation for photosynthesis?
light energy
CO2 + water ————> glucose + oxygen
chlorophyll
What is DNA made of?
Two strands which form a double helix, each strand made from nucleotides
What are the base pairs of DNA?
A - T
G - C
What does DNA do?
Carries genetic information of an organism
What is DNA organised into?
Chromosomes which are millions of base pairs long
What is a section of base pairs called?
A gene
What does a gene code for?
A protein
What are DNA and ribosomes linked by?
mRNA
What is osmosis?
The movement of water molecules from a high water concentration to a low water concentration
Does osmosis require energy?
No, it is with the concentration gradient (passive transport)
If a plant cell is in a hypertonic solution what happens to it?
It shrinks and becomes plasmolysed
What happens to a plant cell in a hypotonic solution?
It swells and becomes turgid
What happens to an animal cell in a hypertonic solution?
It shrinks
What happens to an animal cell in a hypotonic solution?
It swells and bursts
What is diffusion?
The movement of molecules from a high concentration to a low concentration
Does diffusion require energy?
No, it is down concentration gradient
Name an example of substances that can enter/leave cell through diffusion
Oxygen, glucose, amino acids, carbon dioxide
Where does stage one of photosynthesis take place?
In the granum
What is the cell membrane made of?
Two layers that are selectively permeable. Proteins + a double lipid layer
What is in an animal cell?
Cell membrane, nucleus, ribosomes, mitochondria
What is in a plant cell?
Cell membrane, nucleus, ribosomes, mitochondria, chloroplasts, vacuole, cell wall
What is in a fungal cell?
Cell membrane, nucleus, ribosomes, mitochondria, vacuole, cell wall
What is in a bacteria cell?
Cell membrane, ribosomes, cell wall, cytoplasm, plasmid, circular chromosome
What does the cell membrane do?
Regulates what can enter/leave cell
What is the function of the nucleus?
Controls cell’s activities, passes genetic information from cell to cell
Where do cellular reactions take place?
Cytoplasm
What takes place in the mitochondria?
Aerobic respiration and ATP production
Where does protein synthesis take place?
Ribosomes
What is a plasmid?
A small DNA molecule that can replicate independently of chromosomal DNA
What is active transport?
Movement of molecules from a low concentration to a high concentration
Does active transport require energy?
Yes, it is against the concentration gradient
What are proteins made of?
Amino acids joined together by peptide bonds to form polypeptide chains
What determines the shape and function of a protein?
The sequence of amino acids
What two shapes can proteins be?
Fibrous or globular
Name a type of protein
Enzymes, hormones, antibodies, haemoglobin
How many stages is in mitosis?
6
What carries the genetic information of a cell?
Chromosomes in the nucleus
How many chromosomes does a single cell contain?
46 (23 pairs)
What enzymes made of?
Proteins
Name a biological catalyst?
Enzymes
What is the active site a specific shape for?
A substrate
The shape of an enzyme is determined by what?
Sequence of amino acids
What is a degradation reaction?
The break down of complex molecules into simpler ones
What a synthesis reaction?
Build up of complex molecules from simple ones
What factors affect enzyme activity?
Temperature, pH and supply of substrate
What happens when the factors of enzyme activity is too high or low?
Enzyme is denatured
What is respiration?
The process in which cells obtain energy
When does aerobic respiration occur?
When oxygen is available
When does anaerobic respiration occur?
When oxygen is not available
The energy released from respiration is used to synthesise what?
Molecules of ATP
What is ATP needed for?
Active transport, muscle contraction, cell division, protein synthesis
Where does aerobic respiration occur?
Mitochondria
What is stage one of aerobic respiration called and where does it take place?
Glycolysis in the cytoplasm
What happens in stage one of respiration?
Glucose is converted into pyruvate
What is the name of stage two of respiration and where does it take place?
Citric acid cycle in the mitochondria
In stage two of respiration, what is oxygen converted into?
Carbon dioxide
Is oxygen needed for stage two of respiration?
Yes
What is the name of stage three of respiration and where does it take place?
Cytochrome system in the cristae
How many molecules of ATP is produced as a final product?
38
What is the word equation for aerobic respiration?
Glucose + oxygen —–> CO2 + water + energy
What is the word equation for anaerobic respiration in animals?
Glucose lactic acid + energy
How is the lactic acid removed in your body?
By paying back oxygen dept (recovery time)
What is the word equation for anaerobic respiration in plants?
Glucose ——> ethanol + CO2 + energy
Where does anaerobic respiration in plants take place?
Cytoplasm
Give an example of a enzyme breakdown reaction
amylase
Starch ———-> maltose
Give an example of an enzyme synthesis reaction
phosphorylase
Glucose-1-phosphate —————–> starch
