Chapter 26: Nucleic acids and Protein Synthesis

Translation

________ is the process by which the genetic messages carried by RNA are decoded and used to build proteins.

Proteins

________ are polypeptides, carbohydrates are polysaccharides, and nucleic acids are polynucleotides.

cell nucleus

They are formed in the ________ and transported out to the ribosomes, where proteins will be synthesized.

Deoxyribonucleotide

________ is a nucleotide that contains 2- deoxy- d- ribose (monophosphate examples are dAMP, dTMP, dCMP, and dGMP)

Watson Crick

According to the ________ model, a DNA molecule consists of two polynucleotide strands coiled around each other in a helical, screw- like fashion.

Ribonucleotide

________ is a nucleotide that contains d- ribose- monophosphate examples are AMP, uridine monophosphate (UMP), cytidine monophosphate (CMP), and guanosine monophosphate (GMP)

genetic information

The ________ is read as a sequence of codons- triplets of bases in DNA that give the sequence of amino acids in a protein.

DNA

The difference between ________ and RNA is found in the sugar portion of the molecules.

Nucleotides

________ carrying bases complementary to the template bases between a control segment and a termination sequence are connected one by one to form mRNA.

orderly tangle

When a cell is not actively dividing, its nucleus is occupied by chromatin, which is a compact, ________ of deoxyribonucleic acid (DNA), the carrier of genetic information, twisted around organizing proteins known as histones.

termination step

The ________ consists of separation of the two ribosome subunits, the mRNA, and the protein.

total molecular mass

Each ribosome is a complex consisting of about 60 % ribosomal RNA (rRNA) and 40 % protein, with a(n) ________ of approximately 5, 000, 000 amu.

transcription

In ________, one DNA strand serves as the template and the other, the informational strand, is not copied.

nitrogenous bases

A molecule composed of either ribose or deoxyribose and one of the five ________ found in DNA and /or RNA is called a nucleoside.

double helix

The ________ resembles a twisted ladder, with the sugar- phosphate backbone making up the sides and the paired bases, the rungs.

tRNA

Each ________ has at one end an anticodon consisting of three bases complementary to those of the mRNA codon that specifies the amino acid it carries.

Elongation

________ proceeds as the next tRNA arrives at the second binding site, its amino acid is bonded to the first one, the first tRNA leaves, and the ribosome moves along so that once again there is a vacant second site.

Replication

________ is the process by which a replica, or identical copy, of DNA is made when a cell divides, so that each of the two daughter cells has the same DNA.

DNA replication

________ begins in the nucleus with partial unwinding of the double helix; this process involves enzymes known as helicases.

polynucleotides

They are ________ of varying length that carry the same code for proteins as does the DNA.

RNA

In ________, the sugar is d- ribose, except hereafter simply referred to as ribose, as indicated by the name ribonucleic acid.

chromosome

Each ________ contains a different DNA molecule, and all of the DNA is duplicated so that each new cell receives a complete copy.

cyclic compound

Each nucleotide has three parts: a five- membered cyclic monosaccharides, nitrogen- containing ________ known as a nitrogenous base, and a phosphate group.

expression of genetic information

The duplication, transfer, and ________ occur as the result of three fundamental processes: replication, transcription, and translation.

cell division

During ________, chromatin becomes even more compact and organizes itself into chromosomes.

primary transcript mRNA

The ________ (or hnRNA) is identical to the matching segment of the informational strand but with uracil replacing thymine.

DNA

In ________, the sugar is 2- deoxyribose, giving deoxyribonucleic acid.

Transcription

________ is the process by which the genetic messages contained in DNA are read and copied.

RNA

________ and DNA also differ in size and structure- RNA strands are not as long as DNA molecules.

DNA

The function of one type of RNA is to put the information stored in ________ to use.

Each nucleotide has three parts

a five-membered cyclic monosaccharides, nitrogen-containing cyclic compound known as a nitrogenous base, and a phosphate group

It was also found that the proportions of each (A/T

G/C) vary from one species to another

The duplication, transfer, and expression of genetic information occur as the result of three fundamental processes

replication, transcription, and translation

Ribosomal RNAs

Outside the nucleus but within the cytoplasm of a cell are the ribosomes-small granular organelles where protein synthesis takes place

Messenger RNAs

The messenger RNAs (mRNA) carry information transcribed from DNA

Transfer RNAs

The transfer RNAs (tRNA) are smaller RNAs that deliver amino acids one by one to protein chains growing at ribosomes