Cell Organelles In An Epithelial Cell As Biology

Front 1

What is the ultrastructure of a cell?

Back 1

Each cell has an internal structure that suits its function

Front 2

What type of cell is an epithelial cell?

Back 2

A eukaryotic cell

Front 3

What are the characteristics of eukaryotic cells?

Back 3

Have a distinct nucleus

Possess membrane-bounded organelles

Front 4

Name an example of a prokaryotic cell

Back 4

Bacteria

Front 5

What type of microscope is used to see the organelles in a cell?

Back 5

Electron microscope

Front 6

What is inside the nucleus?

Back 6

Contains organism's hereditary material (DNA) and controls cell's activity

Front 7

What is the nuclear envelope?

Back 7

A double membrane that surrounds the nucleus

Its outer membrane is continuous with the endoplasmic reticulum of the cell and often has ribosomes on its surface

Front 8

What is the function of the nuclear envelope?

Back 8

Controls the entry and exit of materials in and out of the nucleus

Contains reactions taking place within it

Front 9

What is the function of the nuclear pores?

Back 9

Allow passage of large molecules, such as messenger RNA, out of the nucleus

Front 10

What is the nucleoplasm?

Back 10

The granular, jelly-like material that makes up the bulk of the nucleus

Front 11

What is chromatin?

Back 11

The DNA found within the nucleoplasm

This is what chromosomes are when the cell is not dividing

Front 12

What is the nucleolus?

Back 12

Small spherical body within the nucleoplasm

Front 13

What is the function of the nucleolus?

Back 13

Manufactures ribosomal RNA and assembles ribosomes

Front 14

What are the 3 functions of the nucleus?

Back 14

1. Act as a control centre of the cell through the production of mRNA and hence protein synthesis

2. Retain genetic material of the cell in the form of DNA or chromosomes

3. Manufacture ribosomal RNA and ribosomes

Front 15

What is a mitochondrion made up of?

Back 15

Double membrane

Cristae

The matrix

Front 16

What is the function of the double membrane?

Back 16

The outer one controls the entry and exit of material

The inner membrane is folded to form extensions known as the cristae

Front 17

What is the function of the cristae?

Back 17

Shelf-like extensions which provide a large surface area for the attachment of enzymes involved in respiration

Front 18

What does the matrix contain?

Back 18

Protein

Lipids

Traces of DNA

Front 19

What does the matrix do with its contents?

Back 19

Allows mitochondria to control the production of their own proteins

Front 20

What is the endoplasmic reticulum?

Back 20

An elaborate, three-dimensional system of sheet-like membranes, spreading through the cytoplasm of the cells

Continuous with the outer nuclear membrane

Membranes enclose flattened sacs called the cisternae

Front 21

What are the two types of endoplasmic reticulum?

Back 21

Rough endoplasmic reticulum

Smooth endoplasmic reticulum

Front 22

What is present on the outer surface of the RER?

Back 22

Ribosomes

Front 23

What are the functions of the RER?

Back 23

1. Provide large surface area for the synthesis of proteins and glycoproteins

2. Provide pathway for the transport of materials throughout the cell, especially protein transport

Front 24

What is the physical appearance of the SER?

Back 24

Lacks ribosomes on its surface

More tubular appearance

Front 25

What is the function of the SER?

Back 25

Synthesis, store and transport lipids and carbohydrates

Front 26

What does the Golgi apparatus consist of?

Back 26

Stack of membranes that make up flattened sacs with small rounded hollow structures called vesicles

Front 27

What is the correct term for flattened sacs?

Back 27

Cisternae

Front 28

What is the process of the Golgi apparatus?

Back 28

-Modifies proteins from RER by adding non-protein components e.g carbohydrate

-Also labels proteins, allowing them to be sorted and sent to correct destinations

-Once sorted, modified proteins and lipids are transported in vesicles which are regularly pinched off from the ends of Golgi cisternae

-Vesicles move to cell surface, where they fuse with membrane and release contents to outside

Front 29

What are the functions of the Golgi apparatus?

Back 29

-Add carbohydrate to protein to form glycoproteins

-Produce secretory enzymes e.g those secreted by pancreas

-Secrete carbohydrate e.g those used to make cell walls in plants

-Transport, modify and store lipids

-Form lysosomes

Front 30

When are lysosomes formed?

Back 30

When vesicles produced by Golgi apparatus contain enzymes

Front 31

What do lysosomes isolate?

Back 31

Isolate potentially harmful enzymes from rest of cell before releasing them

Front 32

Where do lysosomes release enzymes into?

Back 32

Outside the cell

Into a phagocytic vesicle within the cell

Front 33

What are the functions of lysosomes?

Back 33

-Break down material ingested by phagocytic cells e.g white blood cells

-Release enzymes to the outside of cell (exocytosis) in order to destroy material around cell

-Digest worn out organelles so that useful chemicals which they are made from can we re-used

- Completely break down cells after they have died (autolysis)

Front 34

What are ribosomes?

Back 34

Small cytoplasmic granules found in cells

Front 35

Where are ribosomes found?

Back 35

Cytoplasm

RER

Front 36

What are the two types of ribosomes?

Back 36

80S type

70S type

Front 37

Where are the two types of ribosomes found?

Back 37

80S type- Eukaryotic cells

70S type- Prokaryotic cells

Front 38

What is in the both subunits of a ribosome?

Back 38

Ribosomal RNA

Protein

Front 39

What is RNA?

Back 39

Ribonucleic acid

Its principal role is to act as a messenger carrying instructions from DNA for controlling the synthesis of proteins

Front 40

What are microvilli?

Back 40

Finger-like projections of an epithelial cell

Increases surface area to allow more efficient absorption