Commonly forgotten Flashcards
what is degenerate code?
advantage?
most codons (triplet) code for more than one amino acid. it lessens the chance of deleterious mutations as codon will code for same thing
what is non-overlapping code?
advantage?
codons are separate.
what is an anticodon?
the three complementary bases on the tRNA (NOT mRNA)
why is code not overlapping?
in overlapping code, a mutation that changed one base would lead to the changing of three consecutive amino acids in the protein sequence
what is each strand of DNA called during protein synthesis?
- template strand (one which is read by RNA polymerase)
- coding strand (strand whose base sequence is identical to the base sequence of the RNA transcript produced- although with thymine replaced by uracil)
what elements do lipids comprise of?
carbon, hydrogen and oxygen atoms, phosphorus, nitrogen, sulfur (others)
what elements do carbohydrates comprise of?
only carbon, hydrogen and oxygen
what elements do proteins comprise of?
carbon, hydrogen, and oxygen atoms, all proteins contain nitrogen and sulfur atoms, phosphorus (others)
what does semi-conservative mean?
- each strand acts as a template for the new strand
- new contains one old one new
where are the three checkpoints in the cell cycle?
- near end of G1
- end of G2
- end of mitosis
what are glycolipids and glycoproteins?
BOTH CARBOHYDRATES.
glycolipid attached to PHOSPHOLIPID
glycoprotein attached to MEMBRANE PROTEIN
how much cholesterol will a cell that functions at high temperatures have?
a lot.
to keep the membrane rigid (attractions between cholesterol and phospholipids)
properties of ATP?
- universal energy store
- small
- water-soluble
- bonds with intermediate (enough) energy
- easily regenerated
what happens in prophase?
chromatin condenses so chromosomes become visible, nucleolus disintegrates, mitotic spindle formation begins and chromosomes are attached to spindle fibres by centromeres.
what happens during metaphase?
chromosomes align along the metaphase plate along the spindle fibres