Cells: Viral Structure And Body Organisation

Question 1

Stomach function

Answer 1

1.Muscles to churn and mix stomach contents
2.Epithelium to protect the stomach wall and produce secretions
3.Connective tissue to hold together the other tissues

Question 2

Organ definition

Answer 2

Aggregation of tissues performing specific functions

Question 3

Organ system definition

Answer 3

Groups of organs working together to perform specific functions

Question 4

Epithelial tissue

Answer 4

Found in animals and consists of sheet of cells
They line the surface of organs and have a protective or secretory function
Thin flat cells that line organs where diffusion takes place. E.g. alveoli, ciliated epithelium that lines a duct such as the trachea

Question 5

Tissue definition

Answer 5

A group of specialised cells with a similar structure working together to perform a specific function, often with the same origin

Question 6

Viruses are not classed as living because…

Answer 6

They are acellular (not made up of cells)
They do not respire
They can not reproduce without a host cell

Question 7

Virus structure

Answer 7

All have:
- genetic material (nucleic acid: stored as DNA or RNA) enclosed in a protein coat called a capsid
- Attachment Proteins (to allow identification and attachment to a host cell)
Some have:
- Lipid enveope
- Matrix
- reverse transcriptase (enzyme)

Question 8

Virus size

Answer 8

Smaller than bacteria, ranging from 20-300nm