IB Bio 25 - topic 2.2.5

Nucleus

Stores DNA and controls cell activities such as gene expression and cell division.

Nuclear envelope

Double membrane surrounding the nucleus that separates it from the cytoplasm and contains pores for transport.

Nucleolus

Produces rRNA and assembles ribosomal subunits used to make ribosomes.

Ribosomes (80S)

Site of protein synthesis

Rough endoplasmic reticulum (RER)

Synthesizes and folds proteins that are exported, secreted, or inserted into membranes.

Smooth endoplasmic reticulum (SER)

Synthesizes lipids and phospholipids, detoxifies chemicals, and stores calcium ions.

Golgi apparatus

Modifies, sorts, and packages proteins and lipids into vesicles for transport.

Mitochondria

Site of aerobic respiration and ATP production for cellular energy.

Lysosomes

Contain digestive enzymes that break down macromolecules, pathogens, and old organelles.

Cytoskeleton

Network of protein filaments that maintains cell shape and helps transport materials.

Centrioles

Organize microtubules and help form the spindle during cell division in animal cells.

Plasma membrane

Selectively permeable membrane that controls movement of substances in and out of the cell.

Cytoplasm

Jelly

Chloroplasts

Site of photosynthesis in plant cells where light energy is converted to chemical energy.

Central vacuole

Large storage organelle in plant cells that maintains turgor pressure and stores water and solutes.

Cell wall (plants)

Rigid outer layer made of cellulose that provides support and protection.