Primary succession - refers to succession on a newly exposed site that was not previously occupied by soil and vegetation.

Secondary succession - refers to succession on a site that has already supported life but that has undergone a disturbance.

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#Id: 7530

#Unit 6. System Physiology – Plant

Phototropism Is Mediated by the Lateral Redistribution of Auxin

In response to a directional light stimulus, the auxin produced at the tip, instead of being transported basipetally, is transported laterally toward the shaded side. Two flavoproteins, phototropins 1 and 2, are the photoreceptors for the blue-light signaling pathway that induces phototropic bending in Arabidopsis

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#Id: 7964

#Unit 2. Cellular Organization

Emphysema caused by a point mutation in -antitrypsin, which is normally secreted by hepatocytes and macrophages.

TLS Online TPP Program

#Id: 6585

#Unit 7. System Physiology – Animal

The membranes of late spermatids and spermatozoa contain a special small form of angiotensin converting enzyme called germinal angiotensin converting enzyme (gACE)

TLS Online TPP Program

#Id: 5451

#Unit 7. System Physiology – Animal

The basis for the absolute refractory period is closure of the inactivation gates of the Na+ channel in response to depolarization. These inactivation gates are in the closed position until the cell is repolarized back to the resting membrane potential.

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#Id: 10477

#Unit 4. Cell Communication and Cell Signaling

In certain tumors of antibody-producing B lymphocytes, the cyclin D1 gene is translocated & its transcription is

under the control of an antibody-gene enhancer, causing elevated cyclin D1 production.