Grade 10 Bio - Cell Organelles

Cell Membrane

The cell is surrounded by a flexible double-layered cell membrane. The function of the cell membrane is both to support the cell and to allow some substances to enter while keeping others out. Because of this ability, the cell membrane is called a “semi-permeable membrane.”

Nucleus

The nucleus is the large control centre of a cell, directing all of the cell's activities. Chromosomes that contain your DNA are stored in this organelle. The nucleus is separated from the rest of the cell by the nuclear membrane.

DNA

Chromatin is a “thread-like” material inside the nucleus. This material contains genetic information called DNA (deoxyribonucleic acid), a substance that chromosomes are composed of that makes up the genetic code.

Mitochondria

The mitochondria is sometimes referred to as the powerhouse of the cell. Mitochondria are largely responsible for providing the cell with energy from glucose (sugar) through a process called cellular respiration.

Endoplasmic Reticulum

The endoplasmic reticulum is a three-dimensional network of branching tubes and pockets. It extends throughout the cytoplasm from the nuclear membrane. These fluid-filled tubes transport materials, such as proteins, through the cell.

2 Types of Endoplasmic Reticulum

Smooth Endoplasmic Reticulum (SER)

• No ribosomes attached

• Makes fats or lipids

Rough Endoplasmic Reticulum (RER)

• Has ribosomes attached

• Helps make proteins

Ribosomes

Found on the endoplasmic reticulum or free in the cytoplasm. Proteins are made in this organelle.

Golgi Bodies / Apparatus

Golgi bodies collect and process materials to be removed from the cell. They also make and secrete mucus. Cells that secrete a lot of mucus, such as cells lining the intestine, have many Golgi bodies.

Cytoplasm

All the organelles inside the cell are suspended in the cytoplasm. The cytoplasm is mostly water, but it also contains many other substances that the cell stores until they are needed. Many chemical reactions take place within the cytoplasm.

Cytoskeleton

Network of protein fibers supporting cell shape and anchoring organelles can stretch and contract to move cell parts as needed

Lysosomes

Contain proteins that break down food into smaller particles that the rest of the cell can use. Destroy old cells, recycle the parts. Destroy invaders.

Cell Parts Found only in Plants

Chloroplasts, Cell Wall, Large Central Vacuole (animals have them but they’re smaller)

Chloroplasts

Contain chlorophyll and give leaves their green colour. Absorb light energy which is used in photosynthesis.

Cell Wall

Just outside the cell membrane. Provides support and protection from physical injury.

Vacuole

Plants usually have one large vacuole which takes up most of the space inside the cell. When full of water, turgor pressure keeps the cells plump which keeps the plant’s stems and leaves firm.