Question

The liver is involved in detoxification of many poisons and drugs. Which of the following structures is primarily involved in this process and therefore abundant in liver cells? A) rough ER B) smooth ER C) Golgi apparatus D) nuclear envelope E) transport vesicles Which of the following produces and modifies polysaccharides that will be secreted? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome Which organelle often takes up much of the volume of a plant cell? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome Which animal cell organelle contains enzymes that transfer hydrogen from various substrates to oxygen? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome Movement of vesicles within the cell depends on what cellular structures? A) microtubules and motor proteins B) actin filaments and microtubules C) actin filaments and ribosomes D) centrioles and motor proteins E) actin filaments and motor proteins

Answer 1

30. movement of vesicles within the cell depends on option A- microtubules and motor proteins

microtubules are responsible for a variety of cell movements including intracellular transport and positioning of membrane vesicles, the energy for the movements are derived from ATP hydrolysis.

kinesin and dynein are the prototypes of microtubule motor proteins which move in opposite directions, kinesin towards plus end and dynein towards minus end are also responsible for the movement of vesicles.

26. the structures abundant in liver cell responsible for detoxification - option B smooth endoplasmic recticulum

on detoxification the hepatocytes modify the ammonia into urea for excretion, thereby maintain the homeostasis in the body by acting against the ingested toxins.

liver cells contain plenty of smooth ER , which are tubular and forms an interconnecting network.it is distributed throughout the cytoplasm.

it also enables glycogen that is stored as granules on the external surface of smooth ER to be broken down to glucose, and it also endeavour to detoxify overloads of ethanol derived from excess alcoholic driking and also barbiturates from drug overdose.

the contraction of muscle cells is triggered by the calcium ions , these ions are also released from the smooth endoplasmic reticulum.

27. produces and modifies polysaccharides: option D - golgi apparatus

also called golgi complex found mostly in eukaryotic cells, it is responsible for transporting modifying and packing proteins and lipids into vesicles for delivery to target destinations.

carbohydrates are synthesized in the golgi apparatus, the process of carbohydrate synthesis involves the production of polysaccharides and glycosaminoglycans.

the long unbranched polysaccharides and glycosaminoglycans are attached to proteins in order to form proteoglycans.

more glycosyltransferases are required for the synthesis of complex cell wall polysaccharides.

28. the organelle takes up much volume is option B - vacuole

it is a membrane bound organelle present in plant and fungal cells, they are filled with water containing inorganic and organic molecules including enzymes in solution.

it does not have basic size or shape, structure varies according to the needs of the cell.

it maintains acidic internal pH, maintain hydrostatic pressure, export unwanted substances from the cell.

29. the organelle of cell having enzymes that transfer hydrogen option E - peroxisome

small membrane enclosed organelle which contains enzymes involves in a variety of metabolic reactions.

they contain a single membrane and do not contain DNA or ribosomes, and they are the major sites of oxygen utilization of the cell.

the enzymes in the peroxisome uses molecular oxygen to remove hydrogen atoms from specific organic substrates in an oxidative reaction that produces hydrogen peroxide, the major function of this oxidative reaction is breakdown of the fatty acid molecles.