GRADE 8 BIOLOGY PLS HELP

Membrane proteins can serve a variety of key functions:

Junctions – Serve to connect and join two cells together.

Enzymes – Fixing to membranes localises metabolic pathways.

Transport – Responsible for facilitated diffusion and active transport.

Recognition – May function as markers for cellular identification.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.