cat makeup — Past Paper Questions & Answers

Question 1

Lysosomal membranes

Accepted Answer

Have a significant potential difference across their thickness — Lysosomal membranes and their integral proteins are synthesized in the rough endoplasmic reticulum and then processed and packaged by the Golgi apparatus.

Question 2

Concentration of bicarbonate in the body fluids would best be measured in

Accepted Answer

mg/dl — Bicarbonate concentration in body fluids is typically measured in milliequivalents per liter (meq/L) to reflect its charge and physiological activity.

Question 3

The major class of phospholipids that is present in the cell membrane of human cells is:

Accepted Answer

Phosphatidylcholine — Phosphatidylcholine is the most abundant phospholipid found in eukaryotic cell membranes.

Question 4

The following are cytoplasmic effector molecules, except:

Accepted Answer

Enzymes — Acetylcholine is a neurotransmitter that primarily acts extracellularly, not a cytoplasmic effector molecule.

Question 5

The following is true about peroxisomes except

Accepted Answer

They mainly contain hydrolases unlike other lysosomes that contain oxidases — Peroxisomes are distinct organelles from lysosomes and contain oxidases, not hydrolases.

Question 6

Normal saline solution contains

Accepted Answer

4.5 g of NaCl per 500ml — Normal saline is 0.9% NaCl, which means 0.9g per 100ml, or 4.5g per 500ml.

Question 7

The spliceosomes that perform autosplicing of mRNA during posttranscriptional modification

Accepted Answer

Are usually derived from neighbouring cells — Autosplicing is performed by ribozymes (self-splicing introns), which are RNA molecules that catalyze their own excision from the pre-mRNA.

Question 8

Immunoglobulins mediating the late phase of inflammation include

Accepted Answer

IgM — IgG is involved in various immune responses, including the late phase of inflammation through complement activation and opsonization.

Question 9

One mole of any substance

Accepted Answer

Is the gram-molecular weight of the substance divided by its valence — One mole of any substance contains Avogadro's number (approximately 6.022 x 10^23) of particles (atoms, molecules, or ions).

Question 10

The following statement is TRUE about the development of immune cells:

Accepted Answer

Natural killers cells arise directly from the common lymphoid progenitor — Natural killer cells develop from the common lymphoid progenitor in the bone marrow.

Question 11

The one disease that is not a lysosomal glycogen storage disorder is

Accepted Answer

Fabry's disease — Tay Sachs disease is a lysosomal storage disorder (a sphingolipidosis) but does not involve glycogen metabolism.

Question 12

The following processes occur during protein synthesis except:

Accepted Answer

DNA translocation. — DNA translocation is not a process directly involved in protein synthesis; protein synthesis involves transcription and translation.

Question 13

All cells

Accepted Answer

can interconvert chemical materials. — All living cells exhibit fundamental characteristics including metabolism (interconverting chemical materials), genetic material (DNA), energy conversion, and being enclosed by a membrane.

Question 14

Which one of the following statements regarding the "head" end of the cell membranes phospholipid molecules is NOT CORRECT?

Accepted Answer

Interacts well with water in the ECF — The head end of a phospholipid is hydrophilic (water-loving) due to its charged or polar groups, interacting well with water in both the ECF and ICF.

Question 15

In both excitable and nonexcitable cells, transmembrane signalling is a vital physiological role of:

Accepted Answer

K+ channels — Calcium channels are crucial for various intracellular signaling pathways in both excitable (e.g., muscle contraction, neurotransmitter release) and non-excitable cells (e.g., second messenger systems, gene expression).

Question 16

Osmolal concentration

Accepted Answer

refers to change in freezing point of solvent caused by amount of solute in grams per Kilogram of solution — Osmolality is a colligative property, meaning it depends on the number of solute particles, and is commonly measured by its effect on freezing point depression.

Question 17

Endoplasmic Reticulum associated ribosomes mainly synthesize:

Accepted Answer

Structural proteins for unit membranes and lysosomal enzymes — ER-associated ribosomes synthesize proteins destined for secretion, membrane insertion, or delivery to organelles like lysosomes.

Question 18

The cell's cytoskeleton includes

Accepted Answer

Endoplasmic reticulum, microtubules and intermediate filaments — The cytoskeleton is composed of microtubules, microfilaments (actin filaments), and intermediate filaments, with MTOCs organizing microtubules.

Question 19

The best method of measuring osmotic pressure of plasma would be to

Accepted Answer

compare it's freezing point with that of water at STP — This method directly measures the hydrostatic pressure required to prevent osmosis across a semipermeable membrane.

Question 20

The mitochondria very likely perform the following tasks except:

Accepted Answer

hormone packaging. — Hormone packaging is primarily a function of the Golgi apparatus, not mitochondria.

Question 21

While destination of proteins being synthesized is determined at regulator section of the gene the actual identification and tagging is done in the

Accepted Answer

Nucleoplasm as the mRNA leaves the nucleus — The Golgi apparatus is responsible for the final modification, sorting, and packaging of proteins for their specific destinations within or outside the cell.

Question 22

When a cell is deprived of oxygen, its lysosomes tend to burst and release their contents into the cell. (This statement is true.) As a result of this, that cell would be expected to

Accepted Answer

recycle damaged organelles. — The release of lysosomal hydrolytic enzymes into the cytoplasm leads to the breakdown of cellular components, resulting in autodigestion and cell death.

Question 23

The cholesterol associated with cell membranes

Accepted Answer

is an abnormality resulting from a diet high in cholesterol. — Cholesterol is an integral component of cell membranes that influences its fluidity, contributing to the membrane's fluid state at physiological temperatures.

Question 24

The fluid mosaic model describes the plasma membrane as consisting of

Accepted Answer

two layers of phospholipids with protein sandwiched between them. — The fluid mosaic model describes the plasma membrane as a phospholipid bilayer with proteins embedded within or associated with it.

Question 25

The following are known functions of the nucleus except:

Accepted Answer

Produce messenger RNA. — Lysosomes are produced by the Golgi apparatus, not the nucleus.

Question 26

Select the one of the following statements that is NOT CORRECT:

Accepted Answer

The degree of fluidity of the cell membrane significantly affects its function — Phospholipids rarely flip-flop (transverse diffusion) between leaflets; lateral diffusion within a leaflet is common.

Question 27

Membrane phospholipids

Accepted Answer

are made up purely of hydrophilic heads — Phospholipids are amphipathic, with hydrophilic heads facing the aqueous environment and hydrophobic tails forming the core of the bilayer.

Question 28

Insulin is a protein that is produced by certain pancreatic cells and secreted into the bloodstream. (This is true.). Which of the following choices best describes the route of insulin from its production to its exit from the cell?

Accepted Answer

rough ER, Golgi apparatus, smooth ER, cell membrane — Secreted proteins like insulin are synthesized in the rough ER, transported via vesicles to the Golgi for processing, then packaged into vesicles for exocytosis at the cell membrane.

Question 29

The following unit of measurement would be appropriate:

Accepted Answer

Armstrong units to express x 10-10 fraction in reference to volume — Micrometers are a standard unit for measuring the dimensions of cellular structures like microtubules.

Question 30

The most abundant of any single cell type in the human body is

Accepted Answer

Muscle cell — Red blood cells are the most numerous cell type in the human body, essential for oxygen transport.

Question 31

The cell-matrix adhesion molecules and the cell-cell adhesion molecules are extremely important in regulating:

Accepted Answer

Shape of cells — Cell adhesion molecules (CAMs) are critical for maintaining cell shape, tissue architecture, and cell-cell communication.

Question 32

Tetanus toxin and botulinum toxin exert their effects by disrupting the function of SNARES, inhibiting

Accepted Answer

Propagation of the action potential — Tetanus and botulinum toxins are proteases that cleave SNARE proteins, preventing the fusion of synaptic vesicles with the presynaptic membrane and thus inhibiting neurotransmitter release.

Question 33

The cell which would characteristically show all their chromatin appropriately grouped and confined in well organized membranous structure is

Accepted Answer

Hepatocyte undergoing mitosis — Reticulocytes are immature red blood cells that have extruded their nucleus.

Question 34

The function of mitochondria is

Accepted Answer

lipid synthesis. — Mitochondria are the primary sites for aerobic cellular respiration, which generates ATP.

Question 35

Smooth endoplasmic reticulum synthesise

Accepted Answer

Steroids and other lipids

cat makeup — Past Paper Questions & Answers

Questions, Answers & Explanations