Vascular endothelial growth factor (abbreviated as VEGF and pronounced "Veg-F") is a peptide- signaling molecule related to platelet-derived growth factor
VEGF is important in the
formation of the circulatory system because its signaling pathway causes the formation of
new blood vessels in developing embryos during normal development. It also causes the
formation of new blood vessels that supply tumors when the tumor produces and secretes
VEGF. Given what you know about the different kinds of cell signaling and about VEGF,
which of the following is true?
A. VEGF is an endocrine-signaling molecule
because it circulates in the bloodstream
inside of platelets.
B. VEGF is an endocrine-signaling molecule
because it is released from platelets into the
bloodstream where it is carried throughout
the body, causing widespread activation of
PDGF receptors on cells in a variety of
tissues.
C. VEGF is a paracrine signaling molecule
because it binds to VEGF receptors on cells
at the site where new blood vessels are
needed.
C
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A bulging ________ during a(n) ________ contraction will produce a pulse
a. artery, atrial b. artery, capillary c. vein, ventricular d. artery, ventricular e. vein, atrial
Osmoregulation is the control of
a. the internal environment. b. temperature. c. metabolic wastes. d. water and ion balance. e. hyperthermia.
The human chromosomes that do not determine an individual's sex are
What will be an ideal response?
The oxidation of glucose to CO2 and H2O with the subsequent production of energy is best reflected in which of the following statements?
A. Glucose is oxidized in a stepwise fashion beginning with the Enbden-Meyerhof pathway and continuing with the TCA cycle where the remainder of the energy from the glucose is harnessed in oxidized coenzymes, which transport electrons to an electron transport chain where ATP is made by substrate-level phosphorylation. B. Glucose is reduced in a stepwise fashion beginning with the TCA cycle and continuing with a glycolytic pathway where the remainder of the energy from the glucose is harnessed in oxidized coenzymes, which transport electrons to an electron transport chain where ATP is made by oxidative phosphorylation. C. Glucose is reduced in a stepwise fashion beginning with the Entner-Doudoroff pathway and continuing with the TCA cycle where 38 molecules of ATP are made by oxidative phosphorylation. D. Glucose is oxidized in a stepwise fashion beginning with a glycolytic pathway and continuing with the TCA cycle where the remainder of the energy from the glucose is harnessed in reduced coenzymes, which transport electrons to an electron transport chain where ATP is made by oxidative phosphorylation.