举一反三
- Which of the following statement about RNA polymerase in prokaryotes is correct: A: Holoenzyme is composed of five subunits (ααββ′σ) B: Any subunit of holoenzyme cannot bind to DNA separately in vivo C: Core enzyme consists of five subunits(ααββ′ω) D: σ factor helps RNA polymerase to recognize promoter
- The following belong to the protein classification is ( ). A: toxin B: enzyme C: antibiotic D: structural protein
- Which of the<br/>following statement about RNA polymerase in prokaryotes is<br/>correct:() A: Holoenzyme is composed of five subunits (ααββ′σ) B: Any subunit of<br/>holoenzyme cannot bind to DNA separately in vivo. C: Core enzyme<br/>consists of five subunits(ααββ′ω) D: σ factor can<br/>catalyze the synthesis of RNA E: σ factor<br/>helps RNA polymerase to recognize promoter
- Which structure is not secondary structure of the protein？（） A: α-helix B: β- fold C: β- Angle D: subunits
- Most solid materials are ( ) A: Crystal B: Enzyme C: Protein D: Quasicrystal
内容
- 0
Each type of cytoskeletal component is composed of simple protein subunits that associate noncovalently to form filaments of uniform thickness.
- 1
When an enzyme protein is purified and assayed step by step, _____________________________________ with each step. A: oth activity and total protein generally increase B: activity increases but total protein generally decreases C: oth activity and total protein generally decrease D: activity decreases but total protein generally increases
- 2
The<br/>spatial conformation of protein include: () A: α-helix B: β-pleated<br/>sheet C: domatin D: motif E: polymerization<br/>of subunits
- 3
The region of a protein that associates with a ligand, known as its binding site, usually consists of a _____ in the protein surface formed by a particular arrangement of amino acid side chains.
- 4
Each RNA polymerase contains subunits with homology to subunits of the E. coli RNA polymerase as well as additional subunits， which are unique to each polymerase.