Cellular structure and function Flashcards
State 3 differences between a prokaryotic cell and a eukaryotic cell
Prokaryotic cells have no nucleus whereas eukaryotic cells do have a nucleus.
Prokaryotic cells have a single circular chromosome whereas eukaryotic cells have multiple linear chromosomes.
Prokaryotic cells have a plasmid where as eukaryotic cells have no plasmid
Prokaryotic cells have no membrane bound organelles whereas eukaryotic cells do have membrane bound organelles.
State 3 structures a plant (eukaryotic cell) has that an animal (eukaryotic cell) does not.
Plant cells have chloroplasts, cell wall and a permanent vacuole whereas animal cells do not.
Describe the 3 parts of cell theory.
Cells are the basic structural and functional units of life.
All cells come from pre-existing cells.
All living things are made from one or more cells or from products of cells.
Describe the differences between DNA and RNA
DNA has deoxyribose/Thymine/is double stranded whereas RNA has ribose/Uracil/single stranded
Draw and label the monomer of a nucleic acid
Nucleotide (phosphate group, pentose sugar and nitrogenous base)
Define the function of the nucleus
Contains DNA which controls cellular functions by coding for proteins
Define the function of the mitochondrion
Site of aerobic cellular respiration
Define the function of the ribosome
Translates the mRNA code into a ______ polypeptide.
Define the function of the Golgi apparatus
Final modification and packaging of proteins into secretory vesicles
Define the function of the rough endoplasmic reticulum
Folding _________ polypeptides into proteins and transport them into transport vesicles
State the structure of the polymer DNA
Many nucleotide monomers joined together (for all DNA - single circular chromosomes, plasmids and linear chromosomes)
Define the function of a transport vesicle
Transports proteins from the rough endoplasmic reticulum to the golgi apparatus
Define the function of a secretory vesicle
Secretes the protein out of the cell by exocytosis
Define the function of the plasma membrane
Regulates the inputs and outputs of the cell
Define the function of a cell wall
Provides structure and support for the cell
Define the function of a lysosome
Contains digestive enzymes for the destruction of unwanted cellular material
Define the function of the cytosol
Fluid part of the cell where some chemical reactions occur
Define the function of a chloroplast
Site of photosynthesis
Define the function of the permanent vacuole
Stores cell sap
What type of reaction is undertaken in the synthesis of a nucleic acid?
Condensation polymerisation (energy requiring, water is a product)
What are the complimentary base pairing rules?
A-T (DNA, 2 Hydrogen bonds) OR A-U (RNA, 2 Hydrogen bonds)
C-G (DNA + RNA, 3 Hydrogen bonds)
Define proteome
The entire set of proteins expressed by an organism at a given time.
State two structures that are found in a eukaryotic animal cell but not in a eukaryotic plant cell.
Lysosomes and centrosomes
What is a condensation polymerisation reaction?
The chemical elimination of water during the formation of polymers that requires energy
What is a hydrolysis reaction?
Chemical addition of water
What is the primary structure of a protein?
Sequence of amino acids in a polypeptide chain
What bonds joins the primary structure of a protein?
Peptide bonds
What is the secondary structure of a protein?
The primary structure folded into alpha helices, beta-pleated sheets or random folding
What bonds hold the secondary structure of a protein together?
Hydrogen
What is the tertiary structure of a protein?
The 3-D structure composed of folded secondary structures
What bonds hold the tertiary structure of a protein together?
Hydrogen, ionic and disulfide bonds between the amino acid residual groups
What is the quaternary structure of a protein?
Two or more polypeptide chains joined together
How do you improve reliability?
More repeats
What evidence is there to support the theory of Endosymbiosis?
Chloroplasts and mitochondria have their own DNA genome, bacterial ribosomal RNA, double membranes and size
Describe the process that occurs in the nucleus during the production of an insulin protein.
Transcription occurs. This means that DNA unwinds, and RNA polymerase attached to the promoter region for the insulin gene.
DNA template strand is copied into pre-mRNA via complementary base pairing using RNA polymerase.
pre mRNA undergoes RNA processing. Introns are removed, a 5’ methyl G cap and 3’ poly-A tail are added to form mRNA.
mRNA from the insulin gene leaves the nucleus and goes to a ribosome.
Describe the process that occurs at a ribosome during the production of a helicase enzyme.
Translation this means that
Ribosomes read the mRNA code for helicase.
tRNA brings the correct and specific amino acid to the ribosome.
tRNA anticodons are complementary and specific to mRNA codons.
Amino acids are joined together by a peptide bond, in a condensation polymerisation reaction, and a helicase polypeptide is formed.
What happens to the SA:V ratio of an object as it increases in size?
SA:V ratio decreases/gets smaller
Why do cells need a larger SA:V ratio?
To exchange materials efficiently (eg. diffusion)
What is the promoter region of a gene?
A region that does not code for any proteins upstream of the gene
