Golgi Apparatus

The Golgi apparatus, or Golgi complex is  a stack of membrane-bounded channels and vacuoles. They synthesize, package and secrete cell products.

This is the Golgi Apparatus.

Endoplasmic Reticulum

Materials are transported throughout the cell by a system of channels or canals called the endoplasmic reticulum (ER). Chemical reactions take place on the surface of the endoplasmic reticulum. In some places, it is smooth. The rough surface is due to the presence of ribosomes. Cells making proteins contain a large amount of endoplasmic reticulum.

This is the rough endoplasmic reticulum.

Nucleus and Nucleolus

The nucleus is a large structure located inside the cytoplasm of the cell. It is surrounded by its own membrane, called the nuclear membrane, and it contains other organelles (chromosomes and nucleoli). Cell activities are controlled by the nucleus. The nucleolus is located in the nucleus. It is involved in the production of ribosomes.

Cytoplasm

The watery cell fluid that contains the cell organelles is called the cytoplasm. The cytoplasm is located between the plasma membrane and the nucleus. Many life processes take place in the cytoplasm. The cytoplasm exists in two phases- a watery (sol) phase and a thicker (gel) phase.

Plasma Membrane

The plasma membrane is a double-layered structure that surrounds the cell. It provides a boundary between the cell and its environment. In animal cells, it is outside the cell border. In plant cells, it is located inside the cell wall. It's function is to control the passage of materials into and out of the call and to help maintain its shape. The plasma membrane is selectively permeable, which means it lets some materials into the cell while keeping others out.

Osmosis

Water moves freely across the plasma membrane (remember: the plasma membrane is selectively permeable, which means it lets some materials into the cell and keeps others out). Water will move to reach equal concentration on both sides of the cell's membrane. This movement if called osmosis- the diffusion of water across a selectively permeable membrane. The concentration of the substance that is dissolved ub the water controls which direction across the membrane the water will move. The water wants the concentrations of the substances to be equal on both sides. So, the concentration gradient controls osmosis. The water will continue to move across the membrane until the concentrations on both sides are equal.

Hypertonic Solution

The concentration of dissolved substances outside the cell is higher than inside the cell. The water wants the concentrations to be equal. The water will rush out of the cell to the area of higher concentration so that it is the same as the concentration inside the cell. But, the cell will shrink/shrivel up because there is less water inside the cell.