Why bacteria disease are difficult to control

Bacteria attacks the immune system, taking over the immune system cells, turning them to bacteria.  Essentially making the immune system cells attack each other and multiplying.

Viruses pose a challenge to the body’s immune system because they hide inside cells meaning it is harder for them to control the disease. It can easily spread from cell to cell and can be hard to control meaning we look to our immune system to help and to give our body the support it need to fight it off.

(a) is the correct option

Explanation:

Protozoan and helminthic diseases are structurally and functionally similar to human cells

Protozoans

Protozoans are microscopic, one-celled organisms that can either be free-living or parasitic in natureBecause of their property to multiply in humans,it contributes to their survival and also allows serious infection to develop from just a single organismTransmission of protozoa which lives in a human’s intestine to another human(normal) occurs through a fecal-oral route (for example, can occur through contaminated food or water or person-to-person contact)

Helminths

Helminths are large, multicellular organisms that are normally visible to the naked eye in their adult stagesJust like protozoa, helminths can either be free-living or parasitic in natureBut in their adult form, helminths cannot multiply in humansHelminths which are known to be human parasites include: Flatworms– includes tapewormsRoundworms or nematodes– adult forms of these type of worms can reside in the gastrointestinal tract, blood, lymphatic system or subcutaneous tissues

Option B.

Explanation:

Flu virus is a viral infections that affects humans and it's very deadly. It attacks the lungs, throat and nose. It spreads through airborne respiratory droplets, touching contaminated surface, saliva e.t.c.

This disease is difficult to treat because of the antigenic drift of it's exotoxin. There are some drugs that inhibit the enzymes in and out of the cells but it is short lived due to it's antigenic drift properties.

Symptoms include fever, cold, cough, catarrh e.t.c.

The flu virus has the following characteristics this disease is difficult to treat because of the antigenic drift of its exotoxin

Explanation:

Flu is difficult to treat as a result of antigenic drift of its exotoxin

D. difficult delivery

It is associated with A. 

Protozoan and Helminthic Diseases

Explanation:

Their functionally similar and cell structure to human cells.Protozoa caused Most protist diseases in humans . Protozoa make people wiped out when they become human parasites. Chagas malady and sleeping sickness disease caused by Trypanosoma protozoa. The  giardiasis, and Plasmodium protozoa cause malaria by the Giardia protozoa.Many of the most common and destructive human ailments are brought about by a protozoan infection.   Any macroparasitic sickness of people and different creatures in which a piece of the body is tainted with parasitic worms, known as helminths.Schistosomiasis and Soil-transmitted helminthiasis are the most significant helminthiases, and are among the disregarded tropical sicknesses.

The answer would be : can be caused by environmental toxins.

Hope this helps!

The causes of autoimmune diseases are still unknown. The most accepted theory is that external factors are involved in the occurrence of this condition, especially when there is a genetic predisposition and the use of some medications. 

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