Eukaryotic Cells

Question 1

Define the terms eukaryotic and prokaryotic cells

Answer 1

Eukaryotic cells:
Cells that have DNA contained in nucleus, containing membrane bound specialised organelles
Examples of eukaryotic cells include plant and animal cells

Prokaryotic cells:
Cells that have DNA free in the cytoplasm, with no organelles.
Examples of prokaryotic cells inlude bacteria and archaea

Question 2

Outline the structure of the nucleus:

Answer 2

The nucleus is surrounded by the nuclear envelope, a semi permeable double membrane

Nuclear pores on the surface to allow substances to enter/exit

There is a dense nucleolus made of RNA and is the site of rRNA synthesis

Question 3

What is the function of the nucleus:

Answer 3

The nucleus is where DNA is replicated, being the site of mRNA transcription. It also contains the genetic code of each cell

Question 4

Outline the structure of the mitochondria:

Answer 4

The mitochondria is surrounded by a double membrane made up of the inner and outer membrane.

The inner membrane is folded to form cristae being the site of electron transport chain

The fluid centre is the mitochondrial matrix containing loops of DNA, lipids, proteins etc

Question 5

What is the function of the mitochondria?

Answer 5

The mitochondria is the site of aerobic respiration to produce a lot of ATP

Question 6

Outline the structure of chloroplast:

Answer 6

Chloroplast are surrounded by a double membrane, consisting of a inner and outer membrane.

They contain folded membranes embedded with pigment called thylakoids. The thylakoid membranes are stacked up to create granum (one stack = grana)

There is fluid inside the organelle called strong containing enzymes for photosynthesis

They are found in plants

Question 7

What is the function of chloroplasts?

Answer 7

Chloroplasts are the site of photosynthesis for converting solar energy to chemical energy

Question 8

Outline the structure of the Golgi apparatus

Answer 8

The Golgi apparatus consists of stacks of membranes that make up flattened sacs (cisternae) with small rounded hollow structures called vesicles

Question 9

What is the function of the Golgi apparatus?

Answer 9

The Golgi apparatus is where proteins are processed, packaged and modified for export and synthesises glycoproteins

Question 10

Outline the structure of a lysosome

Answer 10

Lysosomes are sacs surrounded by a single membrane containing digestive enzymes

Question 11

What is the function of a lysosome?

Answer 11

A lysosome can hydrolyse phagocytic cells, digest worn out organelles for reuse of materials and perform the exocytosis of digestive enzymes

Question 12

Outline the structure of ribosomes

Answer 12

Ribosomes are small organelles made up of two subunits of protein and rRNA. They are either free in cytoplasm or attached to the endoplasmic reticulum

Question 13

What is the function of ribosomes?

Answer 13

Ribosomes are the site of protein synthesis

Question 14

Outline the structure of the endoplasmic reticulum

Answer 14

The endoplasmic reticulum is a network of folded membranes called cisternae. There are two types roughly endoplasmic reticulum and smooth endoplasmic reticulum.

Question 15

What are the key differences between rough and smooth endoplasmic reticulum?

Answer 15

Rough endoplasmic reticulum has ribosomes on the cisternae allowing protein synthesis to occur

Smooth endoplasmic reticulum has no ribosomes but stores lipids and carbohydrates, synthesising lipids

Question 16

Outline the structure of the cell wall for bacteria and plants

Answer 16

Bacteria has a cell wall made of the polysaccharide murein

Plants have a cell wall made of the polymer cellulose’s microfibrils

Question 17

What is the function of the cell wall?

Answer 17

The cell wall provided mechanical strength and support. It acts as a physical barrier against pathogens.

Question 18

What is the function of the cell wall?

Answer 18

The cell wall provided mechanical strength and support. It acts as a physical barrier against pathogens.

Question 19

Outline the structure of the cell vacuole in plants

Answer 19

The cell vacuole is filled with fluid surrounded by a single membrane called the tonoplast

Question 20

What is the function of the cell vacuole in plants?

Answer 20

The cell vacuole makes cells turgid, providing support. Acts as an temporary store of sugars and amino acids

Question 21

What cells have cell walls?

Answer 21

Plant and fungi cells have cell walls

Question 22

What is the cell wall of a plant cell made up of?

Answer 22

In plants, the cell wall is made of microfibrils of the cellulose polymer

Question 23

What is the cell wall of a fungi cell made up of?

Answer 23

In fungi cells, the cell wall is made up of chitin, a nitrogen containing polysaccharide

Question 24

What is chitin?

Answer 24

Chitin is a nitrogen containing polsaccharide,

Question 25

What is the function of the cell wall?

Answer 25

The cell wall provides structura; strength for the cell

Question 25

What is he function of the plasma membrane?

Answer 25

The function of plasma membrane is to control the movement in and out of molecules

Question 26

Where is plasma membrane found on cells?

Answer 26

Plasma membrane is found on the outside of all cells

Question 27

Explain some common cell adaptations (3pts)

Answer 27

1. Cells have folded membranes or microvillis to increase the surface area to improve diffusion
2. Cells have many mitochondria to allow for the production of large amounts of ATP for active transport
3. Cells have walls that are one cell thick to reduce the distance of the diffusion pathway

Question 28

What is the function of the nuclear pores? Example of this function?

Answer 28

To allow the exchange of substances between the nucleus and cytoplasm. For example ribosomes will leave the nucleus and nutrients/hormones will enter

Question 29

Where are chromosomes found ? What state are they in?

Answer 29

Chromosomes are found in the nucleus in a loosely coiled state

Question 30

What does the nucleolus make?

Answer 30

The nucleolus manafactures ribosomes