Noggin is a secreted protein that is able to accomplish two of the major functions of the organizer:  It induces dorsal ectoderm to form neural tissue It dorsalizes mesoderm cells that contribute to the ventral mesoderm

TLS Online TPP Program

#Id: 3328

#Unit 3. Fundamental Processes

The significance of transcription-coupled repair is that it focuses repair enzymes on DNA (genes) being actively transcribed.

TLS Online TPP Program

#Id: 6525

#Unit 7. System Physiology – Animal

Norepinephrine produces vasoconstriction via  α1 receptors, but epinephrine dilates the blood vessels in skeletal muscle and liver via β2 receptors

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#Id: 1565

#Unit 4. Cell Communication and Cell Signaling

Wnt signal transduction pathways classify into:

1. Canonical wnt pathway (β-catenin dependent)

2. Noncanonical wnt pathways (β-catenin independent)

 

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#Id: 3976

#Unit 2. Cellular Organization

A bacterial type II enzyme, called either topoisomerase II or DNA gyrase, can introduce negative supercoils (decrease Lk). It uses the energy of ATP to accomplish this.

To alter DNA linking number, type II topoisomerases cleave both strands of a DNA molecule and pass another duplex through the break.

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#Id: 9937

#Unit 4. Cell Communication and Cell Signaling

Intracellular bacterial

Intracellular bacterial infections tend to induce a cell-mediated immune response, specifically DTH. 

In this response, cytokines secreted by CD4+ T cells are important—most notably IFN-ϒ, which activates macrophages.