OBJECTIVE LIFE SCIENCE
DEVELOPMENTAL BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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they move with flagella
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they move with pseudopods
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they move with cilia
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they use all three modes of cellular locomotion depending on their position and how far they have to move.
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Detailed explanation-1: -This process is called gastrulation. During gastrulation, the blastula folds in on itself and cells migrate to form the three layers of cells (Figure 13.10) in a structure, the gastrula, with a hollow space that will become the digestive tract.
Detailed explanation-2: -Gastrulation takes place after cleavage and the formation of the blastula, or blastocyst. Gastrulation is followed by organogenesis, when individual organs develop within the newly formed germ layers. Each layer gives rise to specific tissues and organs in the developing embryo.
Detailed explanation-3: -Gastrulation refers to a time of great flux in animal embryos. During gastrulation the cells produced during cleavage begin to move relative to each other. As they move, they change their local environment and come into contact with new cells.