1. What is used in order to avoid contamination in cell culture?
a) Antibiotics
b) Anticoagulants
c) Antipyretics
d) Antiseptics
Explanation: One of the most fundamental requirements while culture cells in vitro, is avoiding contamination. Thus antibiotics are used to do so, their main aim is to stop the growth of bacteria or kill them.
2. Which of the following was the first widely used chemically defined medium?
a) Eagle’s Basal Medium
b) DMEM Medium
c) α-MEM Medium
d) Glasgow’s MEM Medium
Explanation: The Eagle’s basal media was developed in 1955, by Harry Eagle. The DMEM (Dulbecco’s modified Eagle’s media) is medium developed by Dulbecco and Vogt, and published in 1959. α-MEM (Minimum Essential-α modification) is a medium developed by Clifford P Stanners and his colleagues, and published in 1971. Glasgow’s MEM is yet another modification of the Eagle’s Minimum Essential Media, like DMEM and α-MEM.
3. ________________ devised plaque assay for animal viruses using confluent monolayers of cultured cells.
a) George Gey
b) Renato Dulbecco
c) Gregor Mendel
d) Charles Darwin
Explanation: George Gey established the continuous cell line from human carcinoma cells called HeLa cell lines. Renato Dulbecco devised plaque assay for animal viruses using confluent monolayers of cultured cells. Gregor Mendel through his work on pea plants discovered the fundamental laws of inheritance. Charles Darwin developed and proposed a theory about evolution which forms the basis for most of the scientific research.
4. The _____________ tooth enamel and epidermis are formed by differentiation of ectoderm.
a) reproductive system
b) digestive system
c) endocrine system
d) nervous system
Explanation: The nervous system, including the spine, brain and peripheral nerves; tooth enamel and epidermis are formed by the ectoderm’s differentiation.
5. In vertebrates, the ectoderm has five parts.
a) True
b) False
Explanation: There are three parts of the ectoderm in vertebrates. The three parts of the ectoderm are: External ectoderm, neural crest and neural tube. The neuro-ectoderm comprises of the neural crest and neural tube.
6. _____________ discovered the three germ layers.
a) Heinz Christian Pander
b) Alexander Fleming
c) Rosalind Franklin
d) Paul Muller
Explanation: Heinz Christian Pander, a German-Russian biologist, and he was credited for the discovery of the three germ layers that are formed embryogenesis.
7. During the later stages of pregnancy, the ectoderm can be observed first in amphibians and fish.
a) True
b) False
Explanation: During the later stages of pregnancy, the ectoderm can be observed first in amphibians and fish. At the beginning of this process, the embryo divides into many cells, forming a blastula (hollow sphere like structure).
8. The process of ___________ within the ectoderm results in the formation of the neural tube, neural crest, and epidermis.
a) neurulation
b) gastrulation
c) differentiation
d) organogenesis
Explanation: Once the embryo has three germ layers formed, differentiation among the three layers happens, this is followed by the process of neurulation within the ectoderm results in the formation of the neural tube, neural crest, and epidermis. These three components of the ectoderm give rise to a specific type of cell.
9. Epidermal cells give rise to the central nervous system.
a) True
b) False
Explanation: The peripheral nervous system (PNS) and enteric nervous system (ENS), melanocytes, cartilage in the facial region, the dentin of the teeth are created by the CNS and neural crest cells, which are formed by the differentiation of the neural tube cells.
10. Epithelium and Mesenchyme are the origins for all the organs rising from the ectoderm.
a) True
b) False
Explanation: Epithelium and Mesenchyme, two adjacent tissues, are the origin for all the organs rising from the ectoderm such as the nervous system, hair teeth, exocrine glands, etc.