Free embryology MCQ exam model for basic medical students

Explanation:

• Three germ layers → Correct because ectoderm, mesoderm, and endoderm are formed.

• Two germ layers → Incorrect because this occurs in the bilaminar disc.

• Four germ layers → Incorrect because only three exist.

• Neural tube → Incorrect because this forms during neurulation.

• Somites → Incorrect because they form later from mesoderm.

Explanation:

• Ectoderm → Correct because it forms brain and spinal cord.

• Mesoderm → Incorrect because it forms muscles and bones.

• Endoderm → Incorrect because it forms gut lining.

• Neural crest → Incorrect because it gives rise to peripheral nervous system.

• Extraembryonic mesoderm → Incorrect because it forms placental structures.

Explanation:

• Nucleus pulposus → Correct because it is the remnant of the notochord.

• Neural tube → Incorrect because it forms from ectoderm.

• Vertebral column → Incorrect because it develops from sclerotome.

• Spinal cord → Incorrect because it develops from neural tube.

• Somites → Incorrect because they arise from paraxial mesoderm.

Explanation:

• Chorion → Correct because the outer cell mass (trophoblast) forms the chorion.

• Embryo → Incorrect because it develops from the inner cell mass.

• Amnion → Incorrect because it arises from the epiblast.

• Yolk sac → Incorrect because it arises from hypoblast.

• Allantois → Incorrect because it develops later as an outpouching.

Explanation:

• Mesoderm → Correct because heart develops from splanchnic mesoderm.

• Ectoderm → Incorrect because it forms nervous system.

• Endoderm → Incorrect because it forms gut lining.

• Neural crest → Incorrect because it contributes to cardiac outflow tract only.

• Extraembryonic mesoderm → Incorrect because it forms placental structures.

Explanation:

• Ampulla of uterine tube → Correct because it is the most common site of fertilization.

• Uterus → Incorrect because implantation, not fertilization, occurs here.

• Ovary → Incorrect because ovulation occurs here.

• Cervix → Incorrect because it is not involved in fertilization.

• Infundibulum of uterine tube → Incorrect because it receives the ovum but fertilization usually occurs later.

Explanation:

• Both maternal and fetal tissues → Correct because placenta consists of chorion frondosum and decidua basalis.

• Maternal tissue only → Incorrect because fetal contribution is essential.

• Fetal tissue only → Incorrect because maternal part is required.

• Amnion only → Incorrect because it does not form placenta.

• Chorion only → Incorrect because maternal tissue also contributes.

Explanation:

• Third week → Correct because gastrulation begins in the third week.

• First week → Incorrect because cleavage and blastocyst formation occur.

• Second week → Incorrect because bilaminar disc forms.

• Fourth week → Incorrect because neurulation occurs.

• Fifth week → Incorrect because organogenesis progresses.

Explanation:

• Development from fertilization to birth → Correct because embryology deals with prenatal development.

• Development of organs → Incorrect because this is a part of embryology, not the full definition.

• Development of tissues → Incorrect because this is histogenesis.

• Development after birth → Incorrect because this is postnatal development.

• Development of cells only → Incorrect because that is cytology.