Revision 2018 Flashcards
What is a double helix?
A double helix is the shape of the DNA molecule, with two strands twisted together in a spiral.
What is mRNA?
mRNA is genetic information that passes out of the nucleus into the cytoplasm.
What are amino acids?
Amino acids are the small molecules that join together in long chains to make proteins. There are 20 different ones.
What is meiosis?
Meiosis is cell division that produces the genes.
What is mitosis?
Mitosis is cell division that produces two cells, for growth + repair.
What is the triplet code?
(3 bases) The triplet code is the information needed to make one amino acid.
What do ribosomes do?
Ribosomes are the place where protein synthesis takes place.
Explain phototropism?
Phototropism is the bending of the plant shoot towards the light.
What are chromosomes?
Chromosomes are long thin, thread- like structures in the nucleus of a cell made from a molecule of DNA. (46 in humans).
Explain One- gene- one protein theory?
One- gene- one protein theory is the idea that each gene on a chromosome controls the production of one protein in the cell.
Explain Genetic switches?
Genetic switches are where genes in the nucleus turn off and are inactive when a cell becomes specialised.
What is an Specialised cell?
A Specialised cell is one that is adapted for a particular type of job.
Explain Tissues?
Tissues are a group of specialised cells of the same type working together to do a particular job.
What are organs?
Organs are parts of plants or animals made up of different tissues.
Explain what “unspecialised” means.
“Unspecialised” means undifferentiated cells, Stem cells are an example.
What are auxins?
Auxins are plant hormones that affects how plant cells develop.
Explain what meristems are?
Meristems are plant cells that are unspecialised and re- grow whole parts of a plant.
What are bases?
The four bases are: A, T, C and G. They are part of DNA.
Explain what proteins are.
A protein is made from one or more polypeptide chains and each polypeptide chain is built from smaller molecules called ‘amino acids’.
Proteins also play a role in movement, structural support, storage, communication between cells, digestion and the transport of substances around the body.
What is the photosynthesis word equation?
The photosynthesis word equation is:
Carbon dioxide + water → Glucose + Oxygen.
What is the symbol equation for this process?
The symbol equation for this process is:
6CO2 + 6H2O → C₆H120₆ + 6O2.
What does a heat shield do?
A heat shield stops heat transferring to the plant.
What does eukaryotic mean?
Eukaryotic is “genetic information that is inside the nucleus of a cell”.
Explain Prokaryotic?
Prokaryotic means “that it’s a cellular organelle that has no internal membrane”.
How do you calculate an RF value?
You would calculate an RF value by this particular formula:
RF= Distance moved by the compound ➗ distance moved by the solvent.
Name 4 uses of glucose in a plant?
Plants use glucose to make:
1) . Starch, fats or oils for storage.
2. ) Proteins eg. enzymes, chlorophyll.
3) . To make cellulose for it’s cell walls.
4) . To make amino acids for protein synthesis.
What is the word equation for aerobic respiration?
The word equation for aerobic respiration is:
Glucose + Oxygen → Carbon Dioxide + Water + Energy.
What is the word equation for this process?
The word equation for this process is:
C₆H12O₆ + O2 → CO2 + H20.
Define metabolism?
Metabolism is all of the chemical reactions that occur within cells.
Explain Genomes.
Genomes is all of the DNA of an organism.
What does asexual mean?
Asexual means one parent.
Define sexual?
Sexual involves two parents ( gametes).
What does phenotype mean?
Phenotype is the physical characteristics shown.