cytology pt 1

What is the plasma membrane?

• • Active barrier separating intercellular fluid from extracellular fluid

• Rivet-like cell junction formed when linker proteins of neighboring cells interlock

• • Part of glycocalynx, serving as identification markers for cell recognition 

What are integral proteins?

• • Firmly inserted into membrane 

• • Most are transmembrane proteins 

• • Have both hydrophobic and hydrophilic regions 

• • Function as: 

  • Transport proteins 

Peripheral proteins are _________ attached to integral proteins.

What are tight junctions?

Tags

NGSS.HS-LS1-2

What are tight junctions?

• Integral proteins on adjacent cells fuse to form an impermeable junction that encircles whole cell 

• • Allow give between cells, reduce possibility of tearing due to tension 

• • Found in tissues subjected to great mechanical stress, such as oskin and heart muscle 

What are desmosomes?

• • Rivet-like cell junction formed when linker proteins of neighboring cells interlock like the teeth of a zipper 

• • Transmembrane proteins form tunnels that allow small molecules to pass from cell to cell 

• • Integral proteins on adjacent cells fuse to form an impermeable junction that encircles whole cell 

What are gap junctions?

• • Integral proteins on adjacent cells fuse to form an impermeable junction that encircles whole cell 

• • Rivet-like cell junction formed when linker proteins of neighboring cells interlock like the teeth of a zipper 

• • Transmembrane proteins form tunnels that allow small molecules to pass from cell to cell 

What are the two types of membrane transport?

• • Passive processes

• • Active processes

• ATP

What is passive transport?

What is passive transport?

• • Occurs down a concentration or pressure gradient without energy

• • Transmembrane proteins form tunnels that allow small molecules to pass from cell to cell 

• • channel filled with aqueous-filled cores, transport ions or water down their concentration gradient