Cells, Tissues and Organs

Question 1

Cells

Answer 1

Simplest structural unit into which the body can be organised

Question 2

Tissue

Answer 2

aggregated of a single type of specialised cell

Question 3

Types of Muscle cell/tissue

Answer 3

skeletal, cardiac and smooth

Question 4

skeletal tissue

Answer 4

attached through other structures to bones and produce movements of the limbs or trunk

Question 5

Cardiac

Answer 5

• Found only in the heart

- when generates force the heart contracts, pumping blood around the body

Question 6

Smooth

Answer 6

Surround many of the tubes in the body

Question 7

neuron

Answer 7

a cell of the nervous system that is specialised to initiate, integrate and conduct electrical signals to other cells

Question 8

epithelial cells/tissue

Answer 8

• specialised for the selective secretion and absorption of ions and organic molecules and protection.
• located on surfaces that cover body or organs and line inner surfaces of tubular and hollow structures within the body.
• one or many layers of cell with an extracellular matrix (basement membrane) separating epithelial cells from underlying tissue
• cuboidal, columnar or squamous

Question 9

Connective tissue/cells (loose vs dense)

Answer 9

• connect anchor and support structures of the body
• loose: loose meshwork found under most epithelial layers
• Dense: tough rigid tissue that makes up tendons and ligaments
• forms ECM around cells
• primary glycoprotein ground substance with protein fibres such as collagen

Question 10

ECM function

Answer 10

• provides a scaffold for cellular attachments

- transmits information through chemical messengers

Question 11

5 types of epithelia

Answer 11

exchange, secretory, transporting, ciliated and protective

Question 12

Exchange epithelia

Answer 12

• one layer of cells (simple epithelia)
• flattened
• have pores between cells to permit easy passage
• found in the lungs and lining blood vessels

Question 13

Transporting

Answer 13

• one layer of colomnar or cuboidal cells
• have tight junctions to prevent movement between cells
• surface area increased by villi
• intestines kidneys

Question 14

protective

Answer 14

• stratified; many layers of cell
• flattened in surface layers, polygonal in deeper layers.
• cells tightly connected by many desmomes
• found in skin and lining cavities that open to the external environment

Question 15

secretory

Answer 15

• one to many cell layers
• columnar to polygonal
• protein secreting cells filled with membrane bound secretory granules and extensive RER, SER etc.

Question 16

Desmosomes

Answer 16

• region between two adjacent cells where apposed plasma membranes are separated by 20 nm
• acumulations of proteins known as dense plaques along cytoplasmic surfaces which serve as anchor points for cadherins (link between cells).

Question 17

tight junctions

Answer 17

• occurs in a band around the circumference of the cell
• joins cell at the apical surfaces
• blocks movement between intracellular space

Question 18

gap junction

Answer 18

• consists of protein channels linking the cytosol of adjacent cells
• allows exchange of small ions