At what stage of animal development do cells first move from the surface of the embryo into the interior, resulting in a two- or three-layered embryo?

A. zygote formation
B. blastulation
C. neurulation
D. gastrulation
E. metamorphosis


Ans: D. gastrulation

Biology & Microbiology

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Photoautotrophs use light energy directly for

A. the reduction of carbon dioxide to glucose. B. the production of ATP and NADPH. C. both the production of ATP and NADPH and the reduction of carbon dioxide to glucose. D. neither the production of ATP and NADPH nor the reduction of carbon dioxide to glucose.

Biology & Microbiology

People often talk about each of our “carbon footprints.” What do you think that means?

a. how much carbon dioxide we exhale b. how much carbon dioxide we inhale c. how much carbon dioxide is generated from photosynthesis d. how much carbon dioxide is generated from the burning of fossil fuels to sustain one’s lifestyle

Biology & Microbiology

Which individual established the connection between genes, meiosis, and fertilization?

a. Gregor Mendel b. Hugo de Vries c. Carl Correns d. Erich von Tschermak e. Walter Sutton

Biology & Microbiology

The root system of mangroves is extensive and penetrates deep into the sediment

Indicate whether the statement is true or false

Biology & Microbiology