In Humans, Identical Twins Are Possible Because

question 23

Multiple Choice

In humans, identical twins are possible because

• A) of the heterogeneous distribution of cytoplasmic determinants in unfertilized eggs.
• B) of interactions between extraembryonic cells and the zygote nucleus.
• C) of convergent extension.
• D) early blastomeres can form a complete embryo if isolated.
• E) the gray crescent divides the dorsal-ventral axis into new cells.

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Definitions:

REM Sleep

A stage of sleep characterized by rapid eye movement, increased brain activity, and vivid dreams, playing a role in memory consolidation and emotional processing.

Beta Waves

Brain waves that are present during awake, alert states of consciousness and are associated with concentration, arousal, and cognition.

Beta Waves

Brainwave patterns associated with active, alert state of mind, characteristic of waking consciousness.

REM Sleep

A sleep phase characterized by rapid eye movement, during which dreams often occur, and the body experiences decreased muscle tone.