Intro Part 2 Flashcards
(almost) all inheritance is based on____: the sequence of _________encodes all instructions needed to build and maintain an organism.
DNA
ACGT nucleotides
A________ is a single DNA molecule together with other molecules (proteins and RNA) needed to support and read the DNA.
chromosome
A_____ is a specific region of a chromosome that codes for a single_______ (linear chain of amino acids).
gene
polypeptide
_______are composed of one or more polypeptides, plus in some cases other small helper molecules (co-factors)._____ do most of the work of the cell.
Proteins
Genes are expressed in a 2 step process:
Transcription
Translation
T or F
All cells in the body have the same DNA, but different genes are expressed in different cells and under different conditions.
True
Genes often have several_____: the same gene in the same chromosomal location, but with minor nucleotide changes that yield slightly different proteins.
alleles
For a given gene, many different alleles can exist in a population (members of the same species), but an individual diploid organism can have___ alleles at most:________
2
one from each parent.
________= having 2 copies of each gene and each chromosome.
Diploid
(where the mitotic spindle attaches)
centromere
(special structures on the ends of chromosomes)
telomeres
(where copying of DNA starts)
origins of replication
(non-functional, mutated copies of genes)
pseudogenes
(intranuclear parasites)
transposable elements a.k.a. transposons
Eubacteria and Archaea. Usually unicellular.
Prokaryotes
No internal membrane-bound compartments: DNA floats free in the cytoplasm.
Prokaryotes
1 circular chromosome (plus optional plasmids, which are also circular)
Prokaryotes
reproduction usually asexual
Prokaryotes
sexual processes (mixing DNA from 2 individuals) occur, but with unequal contributions from the 2 partners
Prokaryotes
transcription and translation simultaneous
Prokaryotes
Plants, animals, fungi, protists. Often multicellular.
Eukaryotes
DNA contained within a membrane-bound nucleus.
Eukaryotes
linear chromosomes (usually more than 1)
Eukaryotes
careful division of chromosomes in cell division: mitosis and meiosis
Eukaryotes