Eukaryotic Cells and Organelles

Question 1

How are plant and animal cells different?

Answer 1

Plant cells have all the same organelles as animal cells, with a few extras:
1. A cellulose cell wall with plasmodesmata
2. A vacuole (contains cell sap)
3. Chloroplasts

Question 2

How are algae and fungal cells like plant cells?

Answer 2

1. Algal cells are a lot like plant cells - they have all the same organelles
2. Fungal cells are like plant cells with two differences - their cell wall is made of chitin, not cellulose, and they don’t have chloroplasts

Question 3

Describe the structure of the cell surface membrane

Answer 3

The membrane found on the surface of plant and animal cells and just inside the cell wall of other cells. It’s mainly made of lipid and proteins

Question 4

What is the function of the cell surface membrane?

Answer 4

Regulates the movement of substances in and out the cell. Has receptor molecules on it which allow it to respond to chemicals

Question 5

Describe the structure of the nucleus

Answer 5

A large organelle surrounded by a nuclear envelope, which contains pores. The nucleus contains chromosomes and one or more structures called a nucleolus

Question 6

What is the function of the nucleus?

Answer 6

Controls the cell’s activities (by controlling the transcription of DNA). DNA contains instructions to make proteins. The pores allow substances to move between the nucleus and the cytoplasms. The nucleolus makes ribosomes

Question 7

Describe the structure of the mitochondrion

Answer 7

Usually oval shaped. The have a double membrane - the inner one is folded to form structures called cristae. Inside is the matrix, which contains enzymes involved in respiration

Question 8

What is the function of the mitochondrion?

Answer 8

The site of aerobic respiration, where ATP is produced. They’re found in large numbers in cells that are very active and require a lot of energy

Question 9

Describe the structure of a chloroplast

Answer 9

A small, flattened structure. It’s surrounded by a double membrane, and also has membranes inside called thylakoid membranes. These membranes are stacked up in some parts of the chloroplast to form grana. Grana are linked together by lamellae - thin, flat pieces of thylakoid membrane

Question 10

What is the function of the chloroplast?

Answer 10

The site where photosynthesis takes place. Some parts happen in the grana, other parts happen in the storm (a thick fluid found in the chloroplast)

Question 11

Describe the structure of the Golgi apparatus

Answer 11

A group of fluid-filled, membrane-bound flattened sacs. Vesicles are often seen at the edges of the sac

Question 12

What is the function of the Golgi apparatus?

Answer 12

It processes and packages new lipids and proteins. It also makes lysosomes

Question 13

Describe the structure of a Golgi vesicle

Answer 13

A small fluid-filled sac in the cytoplasm, surrounded by a membrane and produced by the Golgi apparatus

Question 14

What is the function of the Golgi vesicle?

Answer 14

Stores lipid and proteins made by the Golgi apparatus and transports them out of the cell, via the cell surface membrane

Question 15

Describe the structure of the lysosome

Answer 15

A round organelle surrounded by a membrane, with no clear internal structure

Question 16

What is the function of a lysosome?

Answer 16

Contains digestive enzymes called lysozyme. These are kept separate from the cytoplasm by the surrounding membrane, and can be used to digest invading cells or to break down worn out components of the cell

Question 17

Describe the structure of a ribosome

Answer 17

A very small organelle that either floats free in the cytoplasm or is attached to the rough endoplasmic reticulum. It’s made up of proteins and RNA and is not surrounded by a membrane

Question 18

What is the function of a ribosome?

Answer 18

The site where proteins are made

Question 19

Describe the structure of the rough endoplasmic reticulum (RER)

Answer 19

A system of membranes enclosing fluid-filled space. The surface is covered in ribosomes

Question 20

What is the function of the RER?

Answer 20

Folds and processes proteins that have been made at the ribosomes

Question 21

Describe the structure of the smooth endoplasmic reticulum (SER)

Answer 21

A system of membranes enclosing a fluid-filled space

Question 22

What is the function of the SER?

Answer 22

Synthesises and processes lipids

Question 23

Describe the structure of the cell wall

Answer 23

A ridged structure that surround cells in plant, algae and fungi

Question 24

What is the function of the cell wall?

Answer 24

Supports cells and prevents them from changing shape

Question 25

Describe the structure of the cell vacuole

Answer 25

A membrane-bound organelle found in the cytoplasm of plant cells. It contains cell sap - a weak solution of sugars and salts. the surrounding membrane is called the tonoplast

Question 26

What is the function of the cell vacuole?

Answer 26

Helps to maintain pressure inside the cell and keep the cell rigid. This stops plants wilting. Also involved in the isolation of unwanted chemicals inside the cell

Question 27

What is a tissue?

Answer 27

Specialised cells group together to form tissues. A tissue is a group of cells working together to preform a particular function. Different tissues work together to form organs, Different organs make up an organ system