Page 144 - The Miracle of Hormones

THE MIRACLE OF HORMONES

BEFORE SIGNALING BEGINS

Hormone
Receptor tyrosine kinase
When a messenger molecule reach-
Cell es a cell, it attaches to an antenna
on the cell's membrane. While it is
attached, it relays its message to the
Cytoplasm
antenna. The message passes to the
Enzymatic Module
tail of the antenna that is inside the
cell. After this, the antennae parts
Tyrosine that were previously single come
together in groups of two. The en-
zymes in the body section pair up
‹nternal signaling molecule and add phosphates on each other's
tails, thereby changing the shape of
the tail section. These operations are
like a call to the messenger modules
Inactive SH2 Module
Enzymatic inside the cell.
Module

HORMONE ACTIVATES RECEPTORS SIGNALING PATHWAYS SWITCH ON

Signal from Hormone

Enzyme adds
phosphate to
tyrosine

Phosphate

Active Enzymatic Signal being re-
Module layed to other sig-
naling molecules.

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