Biochem IRAT questions

When amino acids polymerized to form protein, a new peptide bond is formed. This is a ________ reaction

Dehydration reaction

Proteins are the polymer of

Amino acid

In gross/traditional classification proteins are also classified taking an account of the non-protein group. This non-protein group is ______

Lipid

What is a complete protein?

Protein with all nine essential amino acids

Protein missing two or more essential amino acids is called ______

Poor Protein

α- helix has _______ protein in helix

One

In a α-helix, there is a _______ linkage

Intrachain

Following β- plated sheet is _______

Parallel β-plated sheet

A section of the protein structure sufficient to perform a particular chemical or physical task is called ______

Domain

The binding of a ligand changes the conformation of the subunit to which it binds. This conformational change induces a change in neighboring subunits that increase their affinity for the ligand, the phenomenon is called ________

Cooperativity

Unconjugated proteins are made up of ________

Only amino acids

What are loops?

Long-chain amino acid sequence that connects two secondary structures

Motif is a specific binding sites in secondary structure also called as Super secondary structure with unique geometric arrangements of the elements secondary structure. WHic motif is the following structure?

Beta-alpha-beta mtoif

The following arrangement of the Beta-pleated sheet is with loops

3-D arrangement of the individual polypeptide is the ________ structure

Tertiary

During protein synthesis, RNA polymerase initiates mRNA synthesis from

5’ position towards 3’

TATAAA sequence is at the promoter region where RNA polymerase attaches to grow mRNA.

Poly-A chain is the chain of ______

Adenine

During RNA synthesis, _________ nucleotide capped the 5’ position.

Uracil

In collagen, every third amino acid is ________

Glycine

A protein attached to a carbohydrate is called _______

Glycoprotein

Outer layer phospholipids are _________

Phosphatidylcholine and Sphingomyelin

In the plasma membrane, cholesterol molecules are situated in lipid bilayer tails because _______

It is hydrophobic

At high temperature, fluidity of lipid bilayer increased because ___________

The distance between two lipids increases

We can enhance the fluidity of the lipid bilayer by increasing the concentration of cholesterol in the lipid bilayer

Diffusion across the membrane is higher in the case of ________

Lipid bilayer made up of unsaturated fatty acids

Simple diffusion is diffusion through the lipid bilayer. What type of molecule diffuses through the lipid bilayer?

Small non-polar molecules

Inside the cell, calcium ions are stored in ________

Sarcoplasmic Reticulum (SR)

What are Symports?

Moves ions in the same direction

Receptor-mediated endocytosis is _________

Active targeting system

_________ transporter indirectly uses ATP

Secondary active transporter

The following molecule doesn’t require a specific transporter system to diffuse from the lipid bilayer.

Oxygen

________ ion is higher inside the cell (Intracellular), whereas _______ ion is higher outside (Extracellular) the cell.

Na+ and K+

P-type ATPases are involved in ________

Involved in phosphorylation

Where are peripheral proteins located?

On the surface of the outer lipid membrane

On the surface of the inner lipid membrane

What is the primary purpose of cell cycle checkpoints?

To ensure that each phase of the cell cycle is accurately completed before the next phase begins

What is the primary biochemical role of cyclins in the cell?

They act as regulatory subunits that bind and activate CDKs

Why are cyclins called “cyclins”?

Their protein levels oscillate (“cycle”) throughout the phases of the cell cycle

M phase stands for _______

Mitosis

S phase stands for _____

DNA synthesis

What is a kinetochore?

A larger protein complex assembled on the centromere of a chromosome

What is the primary enzymatic function of the Cdc25 protein?

acts as a dual-specificity phosphatase

Unlike the cyclins that regulate them, how do CDK protein levels typically behave throughout the cell cycle?

They remain relatively constant throughout the entire cycle

ATR is a _______

protein kinase that is activated by DNA lesions resulting from incompletely replicated DNA or UV irradiation

cAMP is synthesized by which enzyme?

Adenylyl cyclase

Which is true of p53’s function?

When phosphorylation can stimulate the p21 gene expression

Which of the following terms describe the final stage of the cell division in which the cytoplasm of a parent cell divides to form two distinct daughter cells through the formation of a cleavage furrow?

cytokinesis

The condensation and resolution of sister chromatids depend, at least in part, on a five-subunit protein complex called ________

Condensin

Which of the following are the components of the ATR signaling cascade leading to cell cycle arrest?

cdc25

Which of the following is a component of the ATM signaling cascade leading to cell cycle arrest?

p53