Cells and tissues

Question 1

How many cells are there?

Answer 1

Reference man- 30x 10^12
Red blood cells= 84%
Nucleated= 11%

Question 2

What does the cytoskeleton consist of?

Answer 2

Microfilament- small fibres for support and contraction
Microtubules- movement/ mitosis
Centrosome- Organisation of microtubules, pair of centrioles (cell division)
Cell extensions- projections of plasma membrane, movement

Question 3

How can cells be visualised?

Answer 3

Light microscopy/ fluorescence microscopy/ scanning and transmission electron microscopy

Question 4

What are the type of cells within a tissue?

Answer 4

Parenchymal- main function of tissue
Supporting- scaffolding
Extracellular matrix- cells sit within, produce themselves

Question 5

Types of epithelial tissue

Answer 5

Simple- single layer

Stratified- multiple layers, wear and tear

Question 6

Types of simple epithelial tissue

Answer 6

Squamous- flattened attached to basement membrane
Cuboidal- basement membrane, secretion and absorption kidney
Columnar- Rectangular can be ciliated

Question 7

Types of stratified epithelial tissue

Answer 7

Squamous- keratinised (skin hair), non-keratinised (moist surfaces)
Transitional- pear-shaped, urinary tract only

Question 8

What is pseudostratified epithelium?

Answer 8

Impression of multiple cell layers but each cell attached to basement membrane, columnar ciliated in respiratory tract

Question 9

What are the types of connective tissue?

Answer 9

Loose areolar, adipose, Reticular, dense, cartilage, bone

Question 10

Features of loose areolar connective tissue

Answer 10

Most abundant, connects and supports other tissues, semi-solid matrix of collagen and elastin containing fibroblasts, mast cells, adipocytes and macrophages

Question 11

Features of adipose connective tissue

Answer 11

Contain large fat globules, white= 20-25% adult mass, thermal insulator and energy store/ brown= highly vascularised, new-born

Question 12

Features of Reticular connective tissue

Answer 12

Lymph nodes/ system, matrix consists of reticular fibres, reticular cells and white blood cells

Question 13

Features of dense connective tissue

Answer 13

1. Fibrous- fibres in closely packed bundles, fibroblast cells sit between- coating on bone, tendons
2. Elastic tissue- elastin fibres secreted by fibroblast cells, high degree of recoil, blood vessels and lungs

Question 14

Features of cartilage

Answer 14

Chondrocytes embedded in a collagen and proteoglycan matrix

1. Hyaline- ends of long bones (articulating)
2. Fibrocartilage- intervertebral discs
3. Elastic fibrocartilage- outer ear

Question 15

Features of bone

Answer 15

Osteocytes embedded in mineralised collagen matrix

• Osteoblasts= lay down new bone
• Osteoclasts= remove bone matrix
• Osteocytes= mature bone cells that reside within matrix

Question 16

Types of muscle tissue

Answer 16

Smooth, Cardiac, Skeletal

Question 17

Features of skeletal tissue

Answer 17

Straited multinucleated muscle fibres, voluntary control, moves bones of skeleton

Question 18

Features of smooth tissue

Answer 18

Non-striated, involuntary control, propelling contents along tubes by peristalsis (rhythmic contraction), gut tube and ureter, mononucleated

Question 19

Features of cardiac tissue

Answer 19

Straited, involuntary control, mononucleated, intercalated discs between cells help propagate wave of contraction

Question 20

Types of cells in the nervous system

Answer 20

Neurone, glial cell

Question 21

Features of neurones

Answer 21

Excitable, initiate and receive and transmit information, cell bodies in CNS, axons in PNS

Question 22

Features of glial cells

Answer 22

Non-excitable, support neurones, more numerous- astrocytes, oligodendrocytes, ependymal cells and microglia