Which Element Is Not Necessary for Pollen Tube Formation

question 51

Multiple Choice

Which element is not necessary for pollen tube formation?

• A) Pollen rehydration
• B) Chemical attractants produced by the megagametophyte
• C) Recognition of compatible proteins on the stigma and in the pollen
• D) Close proximity of male and female gametophytes
• E) Functioning tube cell

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Definitions:

Implantation

Attachment of the blastocyst to the endometrium of the uterus, occurring 6 or 7 days after fertilization of the ovum.

Human Embryo

An early developmental stage of human growth and differentiation, starting from fertilization to the eighth week, where major organs and structures begin to form.

Blastocyst

Stage of mammalian embryos that consists of the inner cell mass and a thin trophoblast layer enclosing the blastocele.

Depolarization

The process in which the resting membrane potential becomes less negative, moving towards zero, typically as a precursor to an action potential in neurons.