Consider the following statements:
I: | Cancer is essentially a genetic disease caused by multiple mutational events. |
II: | Cancerous cells are rapidly dividing cells that exhibit contact inhibition. |
III: | Metstatsis is the most feared complication of any cancer. |
Which of the above statements are true?
1. | I and II only | 2. | I and III only |
3. | II and III only | 4. | I, II, and III |
Consider the following statements:
I: | HIV is a retrovirus. |
II: | It infects and destroys the CD4 T-lymphocytes. |
III: | The newer antiretroviral drugs are a cure for HIV infection. |
Which of the above statements are true?
1. | I and II only | 2. | I and III only |
3. | II and III only | 4. | I, II, and III |
Consider the following statements:
I: | Innate immunity is a non-specific type of defense that is present at the time of birth. |
II: | Acquired immunity is pathogen-specific and is characterized by memory. |
III: | Memory-based acquired immunity developed in higher vertebrates based on the ability to distinguish self from non-self. |
Which of the above statements are true?
1. | I and II only | 2. | I and III only |
3. | II and III only | 4. | I, II and III |
Consider the given stages in the life cycle of Plasmodium and choose the correctly matched pair:
1. | A | Merozites infect humans when mosquito bites |
2. | B | The parasite reproduces sexually in liver cells |
3. | C | Symptoms of malaria |
4. | D | Fertilization in the hemocoel of the mosquito |
The importance of the colostrum for the neonate [newborn] is due to the fact that:
1. | The colostrums has large amounts of antibodies that can cross the placenta. |
2. | It can provide protection to the neonate against the pathogens to which the mother is immune. |
3. | The high amounts of brown fat in the colostrum enable neonate to achieve adequate thermoregulation. |
4. | The neonate does not have a well-developed adaptive [acquired] immunity. |
Consider the following statements:
I: | Plasmodium falciparum causes malignant tertian malaria. |
II: | Release of hemosiderin from burst RBCs is responsible for paroxysms of malarial attacks. |
III: | Sporozoites are the infectious forms of Plasmodium. |
Which of the above statements are true?
1. | I and II only | 2. | I and III only |
3. | II and III only | 4. | I, II, and III |
An infant can get passive immunity from:
1. | infection | 2. | colostrum |
3. | anti-Rh Ig | 4. | vaccination with live vaccines |
The antigen-binding sites of an antibody molecule are formed from the molecule's variable regions. Why are these regions described as variable?
1. | They can change their shapes to fit different antigens. |
2. | They change their shapes when they bind to an antigen. |
3. | Their specific shapes are unimportant. |
4. | The amino acid sequences of these regions vary widely among antibodies from different B cells. |
The epitope is the part of the :
1. | antibody that binds to the antigen. |
2. | antibody that binds to the T helper cell. |
3. | antigen that is bound by the antibody. |
4. | hypervariable region of the antibody. |
Opsonization :
1. | is the killing of target cells by cytotoxic T cells. |
2. | is the secretory component of IgA. |
3. | helps increase phagocytosis. |
4. | is the interaction that allows IgG to cross the placenta. |