Jane - core science concepts

What was Robert Hooke known for?

first person recognise cells using a cork and microscope. He was the first to use the term 'cell', and his work set out the foundation of the principles of cell theory.

What are the 3 principles of cell theory?

1. All living things are made up of one or more cells.

2. Cells are the most basic unit of structure and function in all living things.

3. all cells are created by pre-existing cells.

What is the main difference between eukaryotic and prokaryotic cells?

Eukaryotic cells have a nucleus and membrane-bound organelles, whereas prokaryotic cells are usually smaller and have neither.

What are cells?

The building block of life.

What are organelles?

Organelles are specialised structures inside a cell that carry out specific functions, such as mitochondria releasing energy.

What is the role of the nucleus?

controls all the activities in the cell, including cell division.

3 facts about the nucleus.

1. largest organelle

2. surrounded by its own membrane

3. contains genetic material.

What is a cell surface membrane?

It surrounds the cytoplasm of the cell and protects the cells from the surrounding.

3 facts about the cell surface membrane: the cell

1. The membrane enclosing a cell is made up of two lipid layers called a "bilipid" membrane.

2. It allows certain substances into the cell while keeping other substances out. ​

3. The cell membrane also serves to help support the cell and help maintain its shape.

What is the role of the cytoplasm?

contains dissolved nutrients and helps dissolve waste products.

4 facts about the cytoplasm.

1. Jelly-like substance

2. 80% water

3. It fills the cell, and all the organelles are suspended in it

4. ​It is critical for the cell’s survival​

What is the role of the cytoplasm?

Where respiration takes place to create ATP.

3 facts about the mitochondria

1. They contain many folded membranes called cristae, which are covered in enzymes​.

2. They are called the powerhouses of the cell, as they are the main site of AEROBIC respiration.​

3. Some cells have more mitochondria than others. For example, cells that have to perform a lot of work such as heart muscle cells or leg muscle cells, have more.​

What is the role of rough ER?

where most protein synthesis occurs in the cell

What is the role of the smooth ER?

to synthesise lipids in the cell and to detoxification of harmfulsubstances in the cell.

What is the role of the ribosomes?

help in the synthesis of proteins.

What is the role of the Golgi apparatus?

for sorting and sending the proteins produced in the ER, and it modifies proteins made in the ER by adding carbohydrates, for example.​

What is the role of the lysosomes?

Help break down large molecules into smaller pieces that the cell can use.

3 facts about lysosomes

1. They are capsule shaped organelles​

2. They contain a mixture of enzymes capable of destroying old and unwanted cells and organelles.​

3. They destroy unwanted cells using a process called phagocytosis, or cell eating.​

What is the role of the centrioles?

help with celldivision as they can split into two and and form spindles which help separate the chromosomes.

What is the role of the vacuole?

• Store nutrients and waste products​ and assist in regulation of pH and ion balance​

What is the role of the cytoskeleton?

Provides structural support to cells, helps organelles move around the cell, and is involved in cell division and movement of cells.