Eukaryotic Cell Structure

Question 1

Describe the structure of the nucleus

Answer 1

Surrounded by a nuclear envelope(double membrane) which contains nuclear pores which allow the passage of large molecules such as rna to pass out of the nucleus.
Nucleoplasm which makes up the bulk of the nucleus ( jelly like material)
Chromosome consists of protein bound linear dna
The nucleolus it manufactures ribosomal rna and assembles ribosomes

Question 2

What are the functions of the nucleus

Answer 2

To control the cells activities ( transcription of dna)

Retain genetic material of the cell in the from dna and chromosomes

Manufacture ribosomal rna and ribosomes

Question 3

Describe the structure of the mitochondrion

Answer 3

They have a double membrane, inner one is folded to form structures called Cristae(large sa), inside is the matrix which contains enzymes involved in respiration

Question 4

What is the mitochondrion function?

Answer 4

Site of aerobic respiration where atp is produced

Found in large numbers in cells that are very active and require a lot of energy

Question 5

Describe the structure of the chloroplasts

Answer 5

Surrounded by a double membrane (highly selective in what enter and leaves )

Grana are stacks of disc like structures called thylakoids. Within the thylakoids are chlorophyll. Grana are linked together by lamellae

Question 6

Function of chloroplasts

Answer 6

Site where photosynthesis takes place.

Grana membranes has provide a large SA

Question 7

Describe the structure of the rough endoplasmic reticulum

Answer 7

A system of membranes enclosing a fluid filled space, surface is covered in ribosomes

Question 8

Rough endoplasmic reticulum function

Answer 8

Provides large SA for the synthesis of proteins and glycoproteins

Provide a pathway for the transport of materials, especially proteins, throughout the cell

Question 9

Smooth endoplasmic reticulum structure

Answer 9

Similar to RER but has no ribosomes

Question 10

Smooth endoplasmic reticulum function

Answer 10

Synthesise, store and transport lipids and carbohydrates

Question 11

Golgi apparatus structure

Answer 11

A group of fluid filled, membrane bound flattened sacs. Vesicles are often seen on the edge of the sacs

Question 12

Golgi apparatus function

Answer 12

Transport, modify and store lipids

Form lysosomes

Add carbohydrate to proteins from glycoproteins

Produced secretory enzymes

Secrete carbohydrates

Question 13

Golgi vesicles structure

Answer 13

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

Question 14

Golgi vesicles function

Answer 14

Store lipids and proteins made by the Golgi apparatus and transports them out of the cell

Question 15

Lysosomes structure

Answer 15

Surrounded by a membrane, no clear internal structure (type of Golgi vesicles)

Question 16

Lysosomes function

Answer 16

Contain digestive enzymes called lysozymes, can be used to digest invading cells or to break down worn out components of cells

Also

Hydrolyse material ingested by phagocytic cells

Release enzymes to the outside of the cell to destroy material around the cell

Digest worn out organelles so that the useful chemicals they are made of can be re used

Completely break down cells after they die

Question 17

Ribosomes structure

Answer 17

Very small organelle, made up or proteins and rna and not surrounded by a membrane

Question 18

Ribosomes function

Answer 18

The site of protein synthesis

Question 19

What are the 2 types of ribosomes

Answer 19

80s found in eukaryotic cells

70s found in prokaryotic cells

Question 20

Cell wall structure

Answer 20

Rigid structure ( made of carbohydrate cellulose)

In fungi (chitin)

Microfibrils in cellulose Help strengthen the wall

Question 21

Cells wall function

Answer 21

Supports cells and prevents them from changing shape

Question 22

Vacuole structure

Answer 22

A membrane bound organelle

Contains cell Sap- weak solution of sugar and salts

Surrounding membrane is called tonoplast

Question 23

Cell membrane structure

Answer 23

Made mainly of lipids and proteins

Question 24

Cell membrane function

Answer 24

Regulates movement of substances in and out of cells