W2 - Cells, tissues and skin

Question 1

Describe the cytoplasm and its function

Answer 1

It is the watery space between the plasma membrane and the nucleus (contains the cellular organelles and dissolved proteins and nutrients) and is composed of cytosol or ICF
It holds all the components of the cell and protects them from damage

Question 2

Describe the nucleus and its function

Answer 2

It is the control centre of the cell

It contains DNA and instructions for the cell, in particular, protein synthesis

Question 3

Describe the ribosomes (2 types) and their functions

Answer 3

Free ribosomes – floating in the cytosol and produces proteins for use inside the cell
Membrane-bound ribosomes – attached to the ER and produce proteins for export
Site of protein synthesis

Question 4

Describe the endoplasmic reticulum [ER] and its function

Answer 4

Interconnected tubes continuous with the nuclear envelope 
In charge of:
Synthesis
Storage
Transport
Detoxification

Question 5

Describe the smooth ER and its function

Answer 5

No ribosomes attached

Synthesis of lips, cholesterol and steroid based hormones
Involved in detoxification
Storage of calcium ions

Question 6

Describe the rough ER and its function

Answer 6

Studded with ribosomes

Proteins produced by the ribosomes are packaged in a vesicle and exported out of the cell

Question 7

Describe the golgi apparatus and its function

Answer 7

Traffic director
Consists of stacks of flattened sacs

Modifies, concentrates and packages proteins and lipids

Question 8

Describe the mitochondria and its function

Answer 8

Power house
Bean shaped organelle
Enzymes on the surface of inner membrane

Cellular respiration –> releases energy in the form of ATP (Adenosine Triphosphate)

Question 9

Describe the lysosomes and its function

Answer 9

Contain lysosomal (digestive) enzymes

Digests biological material, proteins and cell debris
Disposes of invading bacteria, viruses and toxins
Recycles molecules

Question 10

What are the four main tissue types?

Answer 10

Connective
Epithelial
Muscle
Nervous

Question 11

What is the plasma membrane?

Answer 11

Thin and flexible boundary between the ICF and ECF
Is selectively permeable (allows certain substances through whilst restricting others)
Is made up of a phospholipid bilayer