Tight junctions prevent the diffusion of: 

Macromolecules

Small water-soluble molecules

Ions

Membrane proteins 

Glycolipids

TLS Online TPP Program

#Id: 187

#Unit 5. Developmental Biology

In the frog (Xenopus laevis)

A gradient of the paracrine factor activin (a morphogen), causes concentration-dependent expression differences of two genes in unspecified cells.

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#Id: 10525

#Unit 4. Cell Communication and Cell Signaling

During apoptosis

caspase-3 cleaves the inactive phospholipid scramblase XKR8. 

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#Id: 3680

#Unit 3. Fundamental Processes

IF2 is a GTPase (a protein that binds and hydrolyzes GTP) that interacts with three key components of the initiation machinery: the small subunit, IF1, and the charged initiator tRNA (fMet-tRNAi fMet).

TLS Online TPP Program

#Id: 9526

#Unit 6. System Physiology – Plant

Chewing insects, such as caterpillars, grasshoppers, and beetles, cause the most significant damage to plants. 

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#Id: 6779

#Unit 3. Fundamental Processes

Clustered Regularly Interspaced Short Palindromic Repeats CRISPR consist of repeated sequences (each 30 bp long and highly conserved within a given cluster) interleaved with spacer sequences of similar length but highly divergent sequence.