Question

67. Heat-fixed smears are steamed over boiling water with malachite green primary stain for this type of differential staining technique.
       
Capsule
       
Acid-fast
       
Endospore
       
Flagella

69. The production of all nitrogenous compounds begins with the process called nitrogen fixation.
True
False

72. Inflammation of the kidneys is called
       urethritis
       pyelonephritis
       cystitis
       vaginitis

76. Commercial sterilization involves:
       Killing all living organisms in the product to prevent disease
       Sanitizing the product to a level deemed safe for human health
       Heating the product to a temperature low enough to preserve food quality but high enough to destroy common pathogens such as Clostridium botulinum
       Heating the product to the point that 98% of the common pathogens are destroyed

86. Biofilms are complex communities of a variety of microorganisms (bacteria, fungi, algae, protozoans) that interact through cell signaling and coordinated responses.
True
False

88. Perinatal infections include all the following EXCEPT
       Chlamydial pneumonia
       Cytomegalovirus
       Zika virus
       HIV
       West Nile Virus

Answer 1

67. Endospore

Endospore is formed through a process called sporulation in vegetative cells (bacterium). It occurs when the vegetative cell is under unfavourable environmental conditions. Bacteria such as Bacillus spp and Clostridium spp forms endospore. The aim of forming endospores is to pack all the necessary materials required to survive extreme conditions. Extreme conditions refer to absence of nutrients, extreme heat and chemical changes. Endospores are inactive unlike vegetative cells (active). Till favourable conditions are met, the endospore packs thr genetic material to protect and preserve it so that it can thrive again. Endospores are commonly found in soil and aquatic environments.

The process of sporulation includes 4 steps :

• Replication of bacterial chromosomes
• Formation of forespore by separating the replicated chromosomes by the plasma membrane
• Formation of a second membrane consisting of calcium and dipicolinic acid to cover the forespore. This membrane covers the endospore.
• Release of endospore from vegetative cell

Endospore staining is a differential staining procedure which helps to differentiate structures in an organism under study. Endospore staining is performed to distinguish between vegetative cells and endospores. There are two endospore staining techniques : Schaefer Fulton staining technique; Dorner's method.

Endospore staining is important for identification of endospores in canned food in order to prevent food poisoning and other diseases.

69. True

The process of converting organic nitrogen to its inorganic forms is called nitrogen cycle. Nitrogen cycle takes place in 4 major steps called : fixation, nitrification, ammonification and de-nitrification.

1. Fixation us a process through which atmospheric nitrogen is converted into its usable forms such as NO2-.
2. Nitrification is a process through whuch specialized bacterium converts ammonia into biologically useful forms. First, ammonia (NH3) is converted into nitrite (NO2-) and then NO2- is converted into nitrate (NO3). The specialized bacterium in this process is called nitrobacter.
3. Ammonification is the process through which, organic nitrogen present in dead organisms is converted back into ammonium (NH4) by bacteria or fungi. The converted ammonium can be de-nitrificatied and released into the atmosphere or it can be nitrified and used again.
4. De-nitrification is a process through which nitrate (NO3-) is converted into atmospheric nitrogen gas (NO2).

72. Pyelonephritis

Pyelonephritis is an infection of the urinary tract which leads to the inflammation of the bladder followed by the kidney. It is generally caused by bacteria or viruses. The most common bacteria that causes pyelonephritis is E.coli. Other bacteria such as enterobacter, klebsiella can also cause pyelonephritis. Pyelonephritis is divided into two categories : uncomplicated and complicated. Under,Uncomplicated pyelonephritis, the patient is healthy other than kidney infection. Patients with uncontrolled diabetes, immune disorders, kidney failure, pregnancy fall under the complicated category.

The general symptoms include : fever, tenderness of the flank, nausea, frequent urination, burning sensation while urinating.

Treatments include administration of antibiotics, analgesics, antipyretics. NSAIDs also works well.

76. Option 3.

Commercial sterilization aims at killing endospores of Clostridium botulinum in foos products. The bacteria causes toxic effects when ingested. It is defined as a process through which all pathogenic organisms that can grow under normal conditions are destroyed. In this process, first the food is sealed in a container through a process called as canning. Later, it is heated(minimum of 121°C) under moist conditions for about 15 minutes.

86. True

Biofilms are a complex of aggregate organisms embedded in a self-produced produced matrix of extracellular polymeric substances(EPS) for adherence to the surface and to each other. Biofilms can be formed in all living and non living surfaces. Communication between the microbes in the biofilm is through cell signalling which leads to coordinated responses. When one microbe produces a talk signal another microbe produces a listen signal that leads to a coordinated response.

88. West nile virus

West nile virus is a mosquito borne disease. It causes neurological diseases which leads to death. Often there are no symptoms in patients. Fever, nausea, headache, vomiting, skin rashes and swollen lymph glands are few symptoms. It is generally not transmitted from mother to child. Only a few numbers are recorded.

Other infections such as zika virus, HIV, chlamydial pneumonia and cytomegalovirus are definitely transmitted from the mother to child.