Questions Set-4: Forensic Biology

FORENSIC BIOLOGY

Q1. Which of the following statements is true about the migration of biomolecules in electrophoresis?

a.       The rate of migration is directly proportion to the resistance of the medium

b.      Rate of migration is directly proportional to the current

c.       Low voltage is used for separation of high mass molecules

d.      Rate of migration is inversely proportional to the current

ANSWER:

a.       Rate of migration is directly proportional to the current

EXPLANATION:

The rate of migration of biomolecules in electrophoresis is directly proportional to the current applied. This means that increasing the current will result in faster migration of biomolecules.

Higher currents lead to stronger electric fields, which in turn exert greater force on the charged biomolecules, causing them to migrate more quickly through the medium.

Q2. The principle of radio-immunoassay is based on the interaction of

a.       Unlabelled antigen with a fixed amount of corresponding labelled antigen and antibody

b.      Labelled antigen with a variable amount of antibody

c.       Unlabelled antigen with a fixed amount of antibody

d.      Variable amount of both labelled antigen and antibody

ANSWER:

a.       Unlabelled antigen with a fixed amount of corresponding labelled antigen and antibody

EXPLANATION:

In RIA, the principle is based on the interaction between an unlabelled antigen (the antigen being measured in the sample), a fixed amount of corresponding labelled antigen (radioactively labelled), and antibody.

The unlabelled antigen competes with the labelled antigen for binding sites on a limited amount of antibody. As a result, the amount of labelled antigen bound to the antibody is inversely proportional to the concentration of unlabelled antigen in the sample.

By measuring the radioactivity associated with the bound labelled antigen, the concentration of unlabelled antigen in the sample can be determined.

Q3. Wildlife Protection Act, 1972 was amended in which year?

a.      1999

b.      2000

c.       2002

d.      2012

ANSWER:

c. 2002

Q4. In which one of the following phases of hair growth, the roots shrink into bulb-like shape?

a.      Anagen phase

b.      Catagen phase

c.       Telogen phase

d.      Both anagen and telogen phase

ANSWER:

b.      Catagen phase

EXPLANATION:

During the catagen phase of the hair growth cycle, the hair follicle undergoes regression. This phase marks the transition from active growth (anagen) to a resting state (telogen).

As part of this regression, the roots of the hair shrink into a bulb-like shape. This occurs as the follicle starts to detach from the dermal papilla and prepares for the subsequent shedding of the hair.

Q5. Which of the following can be detected through radioimmunoassay?

A.      metals

B.      toxicants

C.      drugs

D.     antigens

Codes

a.      A, B and C only

b.      A, B and D only

c.       A, C and D only

d.      B, C and D only

ANSWER:

d. B, C and D only

 EXPLANATION:

Radioimmunoassay (RIA) is a sensitive technique used to detect and quantify substances such as drugs, antigens, and toxicants in biological samples.

Q6. Which of the following are true for Lattes Crust method for blood identification?

A.      Depends on antibodies within the stain

B.      Depends on antigens within the satin

C.      The test is more successful on blood crust

D.     The test is more successful on stains in which blood has permeated the substratum

Codes

a.      A, B and C only

b.      A, D and B only

c.       A, C and D only

d.      A, B and D only

ANSWER:

c.       A, C and D only

EXPLANATION:

The Lattes Crust method is particularly effective when blood has dried and formed a crust, as it stabilizes the blood and preserves the antigens for detection.

When blood has penetrated into the underlying material (substratum), it provides a better sample for analysis as compared to superficial stains.

Q7. RFLP (Restriction Fragment Length Polymorphism) analysis determines which of the following?

A.      Power of discrimination (Pd)

B.      Variation in the length of a defined fragment of DNA

C.      Hundreds of variations at each locus

D.     Age of bloodstain

Codes

a.      D, A and C only

b.      B, D and C only

c.       A, B and C only

d.      A, D and B only

ANSWER:

c. A, B and C only

EXPLANATION:

RFLP analysis does not determine the age of a bloodstain. The age of a bloodstain is typically determined using methods such as forensic serology or DNA degradation analysis, which are separate from RFLP analysis.

Q8. Which of the following deals with the study of Forensic palynology?

A.      Seeds

B.      Spores

C.      Pollen

D.     Pistils

Codes

a.      A and B only

b.      B and c only

c.       C and D only

d.      A and C only

ANSWER:

b.      B and C only

EXPLANATION:

Forensic palynology is the study of pollen and spores in forensic investigations.

Q9. Bite marks help in personal identification using which of these types of evidence?

A.      Saliva

B.      Lip prints

C.      Teeth marks

D.     DNA

Codes

a.      A, B and C only

b.      B, C and D only

c.       A, B and D only

d.      A, C and D only

ANSWER:

d. A, C and D only

EXPLANATION:

While saliva might be present in the bite mark, it is not the primary evidence used for identification.

The unique pattern of teeth marks left on an object or victim's skin can be compared to the dental records of suspects for identification purposes.

DNA evidence collected from saliva, skin cells, or other biological material found in the bite mark can help identify the individual responsible for the bite.

Q10. Assertion A: An ellipsoid shape may indicate that a small amount of tissue was taken and only involves the anterior teeth.

Reason R: the amount of skin held in the bite may determine the shape of the mark as per Jakobsen and Keiser-Nielsen (1981)

a.      Both A and R are correct and R is the correct explanation of A

b.      Both A and R are correct but R is NOT the correct explanation of A

c.       A is correct but R is not correct

d.      A is not correct but R is correct

ANSWER:

a.       Both A and R are correct and R is the correct explanation of A

EXPLANATION:

An ellipsoid shape often results from a bite that concentrates force on a specific area, which can occur when biting with only the anterior teeth and taking a small amount of tissue.

An ellipsoid shape may indicate that only a small amount of tissue was taken, as the shape of the bite mark is influenced by the amount of tissue involved.

 

Author:- Bhawana Sharma