Unit 1 Flashcards
What does the cell wall do
Protects and helps a cell to keep its shape
Cell membrane
Controls entry and exit of a cell
Selectively permeable mesning
Only certain molecules can pass through
Chloroplast
Small green disc in plant cells where photosynthesis takes place
Cytoplasm
The jelly inside a cell where organelles are found and where many chemical reaction take place
Nucleus
Contains Genetic information (DNA) as chromosomes
Ribosome
Site of protein synthesis
Mitochondria
Site of aerobic respiration
Organelle
Any part of a cell found in the cytoplasm
Cellulose
The chemical that makes up plant cell walls.
Vacuole
A structure found in the cytoplasm that contains cell sap and helps keeps the cell turgid
Plasmid
Small circular DNA molecules that contain genes. These can be easily removed and inserted into other bacteria cells
What are the cell walls in fungal and bacterial cells made of
Different chemicals
Phospholipids
Molecules that make up a cell membrane along with proteins
Passive transport
Movement of molecules that does not require energy
Concentration gradient
When both sides of cell membranes have different concentrations
Diffusion
The movement of molecules from an area of high concentration to low concentration down a concentration gradient. That doesn’t require energy
Osmosis
The movement of water from an area of high water concentration to an area of low water concentration through a selectively permeable membrane.
Turgid
A plant cell that has filled up with water
Plasmolysed
A plant cell that has shrunk as water has moved out of it
Active transport
The movement of molecules AND ions against a concentration gradient that requires energy
DNA
a molecule found on all life on earth
Genetic code
The sequences of bases on a DNA molecule that is different for all living things
What is the shape of a DNA molecule
Double stranded helix
Gene
A section of DNA that codes for a protein
mRNA
A molecule which carries a complementary copy of the genetic code from the DNA, in the nucleus, to a ribosome
Enzyme
Biological catalysts
Catalyst
Something that speeds up a chemical reaction without being used up
Active site
The part of an enzyme that binds to the substrate
Substrate
The molecule at the start of the reaction that binds with the enzyme
Product
The molecule produced at the end of the reaction
Degradation
A break down reaction
Synthesis
A build up reaction
Enzyme substrate complex
Formed once the enzyme and the substrate bind together
Optimum conditions
The conditions that allow an enzyme to be at its most active
Denatured
When an enzyme changes shape an the rate of the reaction decreases
Steps of enzyme/substrate reaction
Step 1- the enzyme binds to the substrate at the active site
Step 2- an enzyme substrate complex is formed
Step 3- products are formed then released then the enzyme can be used again
What are proteins needed for
S-structural
H-Hormones
A-antibodies
R-Receptors
E-enzymes
What are enzymes made of
Protein
Why do enzymes reactions slow down at high temperatures
Because the enzyme becomes denatured as the enzyme loses its shape and cannot fit into the substrate
Genetic engineering
The process of removing genetic information from one organism and inserting it into another
Required gene
The new gene that’s being inserted into the organism
Source chromosomes
The chromosomes that contain the required gene.
Host bacterial cell
The new cell that the required gene is being inserted into
Steps of genetic engineering
Step 1- identify the section of DNA that contains the required gene from the source chromosome
Step 2-extract the required gene using enzymes
Step 3-extract the plasmid from the bacterial cell
Step 4- insert required gene into bacterial plasmid and seal using enzymes
Step 5- insert plasmid into host bacterial cell to produce a genetically modified organism
Genetically modified organism
Any living organism that has had its genetic material altered by genetic engineering
Respiration
A series of chemical reactions that convert energy from glucose into ATP
ATP
A molecule that cells can use to transfer energy from one of the cell to another
.
Pyruvate
A molecule that is an intermediate step in respiration
Aerobic respiration
Occurs in the presence of oxygen
Fermentation
A form of respiration that does not require oxygen
Lactate
A product of fermentation in animal cells
Ethanol
A product of fermentation in plant and yeast cells
What is ATP needed for
Muscle cell contraction
Mitosis
Protein synthesis
Where does aerobic respiration take place
Mitochondria
How much ATP does aerobic respiration make
A lot.
Steps of glycolysis
Glucose broken down into two molecules of pyruvate.
Which is enough to yield two molecules of ATP
Step two (aerobic respiration)
Each pyruvate is broke down into carbon dioxide and water. Which is enough to yield a large amount of ATP
This is the same in plants, animal and yeast.
Step 2 (Fermentation) in animals
Pyruvate molecules get converted into lactate
which only yields 2 ATP
Step 2 (fermentation) in plant and yeast
Pyruvate is converted into carbon dioxide and ethanol
No additional ATP produced
Example of hormone
Insulin and glucagon
Example of structural protein
Collagen
Example of enzyme
Amylase
