Chapter 18 - A DNA - The Code For Life Flashcards
What’s a chromatin?
A tangled network formed by coiled DNA.
How do such long molecules fit inside the cell nucleus?
The DNA strands are bound to special proteins allied histones.
Explain the structure of the DNA.
It consists of 2 strands of alternating sugars and phosphates with pairs of nitrogen bases forming cross-links between the sugar molecules in the 2 strands. Double helix
What is a nucleotide ?
Units that make up the DNA molecule.
What is Replication?
Interphase.
What is Protein synthesis?
The combining of small molecules to make large molecules.
Where are Amino acids made?
Ribosomes.
What’s the difference between RNA and DNA?
RNA - single strand, uracil
DNA - double helix, thymine
Role of mRNA?
The mRNA passes out of the nucleus and attaches to a ribosome. At the ribosome the amino acids are honked together in a sequence determined by the mRNA.
Explain the role of the tRNA.
Brings the amino acids from the cytoplasm to the ribosomes.
What is gene expression?
The process of copying information from DNA onto messenger RNA and then translating the message into a series of amino acids.
Structure of the mitochondrial DNA.
Small circular molecules.