1. The expression of Holandric genes causes the following genetic trait ______________
a) Haemophilia
b) Huntington’s disease
c) Down’s syndrome
d) Hypertrichosis
Explanation: Genes that are Y linked are called Holandric genes. Conditions such as Hypertrichosis(which is excessive growth of hair) and colour blindness(inability to see and perceive colour) are Y linked disorders, that is they are only inherited by males.
2. The method of DNA replication is _____________
a) conservative
b) semi-conservative
c) non-conservative
d) disruptive
Explanation: In DNA replication , the two daughter strands unwind and are used as template for the formation of a new DNA strand. As a result, one strand in conserved and a new strand is produced by taking the conserved strand as a template. Thus, DNA replication is a semi-conservative process.
3. The DNA binding proteins bind at the _______________
a) Minor groove
b) Major groove
c) Phosphate molecules
d) Pentose sugars
Explanation: The DNA double strands are present as a double-helix as they wound around each another. Due to base stacking, alternative minor and major grooves are formed in the helix. Major groove provide the site for DNA protein binding.
4. DNA denaturation can occur through ________
a) Unwinding of DNA double strand
b) Absorbance of UV rays
c) Decrease in hydrophobic interactions of base stacking
d) All of the mentioned
Explanation: DNA can denature at high temperature, high or low pH, high salinity, chemical denaturants or enzymes or by physical methods such as excess exposure to UV radiation(or any type of radiation for that matter).
5. Human Genome Project was focused on discovering the details of __________
a) sNRPs
b) 3D DNA structure
c) Junk DNA
d) VNTRs
Explanation: The Human Genome Project was an international scientific research project with the goal of determining the sequence of nucleotide base pairs that make up human DNA from a period of 1990 to 2003. The main purpose of these projects was to find out the base sequence of human junk DNA which was different for every individual.
6. One of the main functions of plasma membranes is to enclose the contents of _____________
a) cell
b) organism
c) bones
d) tissue
Explanation: The main function of the plasma membrane is compartmentalization, to enclose all the organelles of the cell and thereby separate them from external hydrophilic environment.
7. Cytosol is the same as cytoplasm.
a) true
b) false
Explanation: Cytoplasm is the collective name of the inner fluid of the cell which is surrounded by a plasma membrane. The soluble part of the cytoplasm is called cytosol, which is not held by any of the cell organelles.
8. Which of the following is allowed in context with a plasma membrane?
a) Inversion
b) Transportation
c) Transversion
d) Transformation
Explanation: Plasma membrane is responsible for transportation of solutes across itself. It is a selectively permeable membrane that allows the transport of a number of molecules and prevents it for others
9. Which type of molecules are involved in responding to external signals received by the cell?
a) Enzymes
b) Nucleic acids
c) Genes
d) Receptors
Explanation: Receptors present on the plasma membrane face outwards in the extracellular environment and are responsible for responding to signals received by cell. These signals are received in the form of small molecules that bind to the receptor consequently generating an orchestration of intracellular action
10. The specific molecules that bind to receptors are _____________
a) Ligands
b) Co-enzymes
c) Substrates
d) Enzymes
Explanation: Receptors present on the cellular membrane are responsible for receiving the signals that come from extracellular environment. These signals are received and the corresponding action is generated upon binding of specific molecules called ligands on the receptors. The ligands have complementary structure with the receptors.