Molecular and Cellular Biology
Covers fundamental concepts in molecular biology, cell biology, and biochemistry including DNA structure, RNA processing, protein trafficking, cellular organelles, mitochondria, cell division, and genetic material.
Questions
The DNA sequence which defines a chromosome includes all of the following except
- centromere
- telomere
- origin of replication
- enhancer
- none of the above
Small nuclear RNAs (Sn RNAs) are involved in the eukaryotic
- transcription
- replication
- reverse transcriptase
- transfer of amino acid
- splicing of mRNA
Nuclear DNA is isolated and sheared into pieces of constant size. The DNA is denatured and then slowly renatured. The first sequence to renature would be
- higly repetitive in frequency
- localized in the nucleolus
- globin genes
- unique in frequency
- all the above
In a patient with muscle weakness and fever due to a mitochondrial myopathy, ATP synthesis is reduced but electron transport is normal. The inner mitochondrial membrane of the patient's muscle might show
- absence of cristae
- defective calcium pump
- missing porin
- open anion channels
- loss of F1 particles
The marker for an enzyme to go from the golgi to lysosome is
- acidic ph
- phosphomannose
- glucosamine
- galactosamine
- protease sensitivity
The enzyme which catalyzes the initial fixation of carbon dioxide in C3 plants has the following properties except
- it can act as an oxygenase in photorespiration
- it is essential in photochemical light reaction
- it is most abundant protein in nature
- it is present in the chloroplast stroma
- it consists of only single chain
A cellular function which is inhibited by colchicine and cytochalasin together but not separately probably involves
- both microtubules and microfilaments
- intermediate filaments
- microtubules only
- microfilaments only
- no component of the cytoskeleton
A protein passing through the golgi and lacking a specific targeting signal will go to the
- extracellular medium
- lysosomes
- endoplasmic reticulum
- chloroplast
- mitochondria
Golgi complex plays no role in
- glycosylation of lipids and proteins
- synthesis of sphingolipids
- concentrating secretory proteins and packaging them by providing enveloping membrane
- metabolism of carbohydrates
- synthesis of proteoglycans
In electrophoresis of DNA molecules, UV illumination of the gel fluoresce the __________ intercalated between the DNA base pairs.
- acridine orange
- ethidium bromide
- uranyl acetate
- feulgen stain
- polyacrylamide gel
The small cytoplasmic RNAs (sc RNAs) in the form of sc RNPs constitute the
- mRNAs
- signal recognition particle
- small nucleolar RNA
- ribosomal RNAs
- t RNAs
Identify the incorrect statement.
- Eukaryotic genetic material is DNA.
- All bacteriophages only contain DNA as their genetic material.
- Retroviruses are single stranded RNA viruses having reverse transcriptase.
- There are mainly animal viruses containing DNA as their genetic material.
- Plant viruses usually contain RNA as their genetic material.
The endosymbiotic origin of plastids from bacteria is suggested by all of the following except
- antibiotic sensitivity of plastid genome
- circular DNA in plastids
- introns in plastid DNA genes
- genome size in plastid
- none of the above
The major events of mitotic prophase include the following except
- chromosome coiling
- DNA replication
- break down of nuclear envelope
- nucleolar disaggregation
- each duplicated chromosome is seen as a pair of sister chromatids
The nucleosomes
- contain only DNA and non histone proteins
- have a core of histones with DNA wound around
- contain histones that are a family of small, negatively charged proteins
- contain histones that cannot be displaced by chromatin remodelling complexes
- containing DNA itself provides energy for its folding