L3 plasma membrane and organelles

What is the plasma membrane structured of?

Mostly the phospholipid bilayer, embedded with cholesterol molecules and proteins.

What is the importance of the plasma membrane?

Regulates the movement of substances in and out of the cell, maintaining homeostasis and protecting the cell's internal environment.

Functions of membrane proteins?

transport, signaling, and structural support.

What is passive transport?

Movement of substances across the plasma membrane without the use of energy (ATP), down the concentration gradient.

What is active transport?

Process that moves substances against their concentration gradient, requiring energy (ATP)

What is co-transport?

Movement of two substances across the plasma membrane simultaneously, involving one substance moving down its gradient while driving another against its gradient. (taylor swift and castle street analogy)

What is the importance of sub-cellular compartments?

Allow for specialization of functions within eukaryotic cells, enhancing efficiency and organization of cellular activities.

What are key organelles in eukaryotic cells (cells with a nucleus)

nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes. (For plants, also central vacuole, and chloroplasts.)

How do organelles contribute to cell function?

By performing specific tasks such as energy production, protein synthesis, and waste processing. Crucial for overall cellular health. (small organs)

cholesterol

Maintains membrane fluidity (prevents from freezing, freezing lowers membrane permeability)