Glands

Question 0

Define a gland.

Answer 0

An epithelial cell/collection of cells, specialised for secretion.

Question 1

What does exocrine and endocrine mean?

Answer 1

Exocrine- with ducts

Endocrine- ductless

Question 2

Name a unicellular gland.

Answer 2

Goblet cell

Question 3

What are the 3 methods of gland secretion?

Answer 3

Merocrine
Holocrine
Apocrine

Question 4

Explain merocrine secretion.

Answer 4

Exocytosis of membrane bound molecules. Method of majority of secretions.

Question 5

Explain apocrine secretion.

Answer 5

Exocytosis of non-membrane bound molecules, e.g. lipids. The apical membrane drapes over it so it can be released membrane bound.

Question 6

In which type of secretion does the membrane become transiently smaller?

Answer 6

Apocrine.

Question 7

Explain holocrine secretion.

Answer 7

Disintegration of the cell, releasing the cell content.

Question 8

What does acinar (alveolar) mean?

Answer 8

Swelling of secretary cells at the end of a tube.

Question 9

Are branched and simple ducts uni or multi cellular?

Answer 9

Multicellular

Question 10

Explain the difference between simple and compound ducts.

Answer 10

Simple- ducts are not branched. However, the 1 duct may be split.
Compound- ducts are branched.

Question 11

Name the 5 types of simple ducts.

Answer 11

1) Simple tubular 2) Simple coiled tubular
3) Simple branched tubular 4) Simple alveolar/acinar
5) Simple branched alveolar

Question 12

Name the 3 types off compound ducts.

Answer 12

1) Compound tubular
2) Compound alveolar/acinar
3) Compound tubloalveolar

Question 13

Explain endocytosis.

Answer 13

Engulf material from outside the cell.

Question 14

Explain transepithelial transport.

Answer 14

Endo and exocytosis are coupled together. Material is endocytosed at 1 surface, is transported in vesicle shuttles across cytoplasm and the material is exocytosed at the opposite surface.

Question 15

Name the organ which has both endocrine and exocrine functions.

Answer 15

Pancreas

Question 16

Describe the structure of the Golgi apparatus.

Answer 16

Stack of disc-shaped cisternae. One side is flat and the other concave. Swellings pinch off as golgi vacuoles.

Question 17

What are the four functions of the Golgi function?

Answer 17

Transport
Sorting
Packaging
Glycosylation (adding sugar)

Question 18

Explain the process of glycosylation and why it is required.

Answer 18

Glycosylation produces complex shaped sugars for specific interactions in the glycocalyx (plasma membrane). Destruction of this by enzymes alters many specific properties of the cell, e.g. cell mobility, communication and adhesion of substrate.

Question 19

After glycosylaion, where do the sugars go?

Answer 19

Majority extruded in secretory vesicles by exocytosis.
Some retained for cell use.
Some enter the glycocalyx.

Question 20

State the 4 mechanisms of secretion and give examples of each.

Answer 20

1) Nervous, e.g. adrenaline
2) Endocrine control, e.g. ACTH
3) Neuro-endocrine control, e.g. nervous cells control ACTH release
4) Negative feedback chemical mechanism, e.g. T3 and T4

Question 21

Are the parotid and submandibular glands, and goblet cells exocrine or endocrine glands?

Answer 21

Exocrine.

Question 22

The parathyroid glands are endocrine. Explain how and what they secrete, their location and their function.

Answer 22

Secrete parathyroid hormone from cheif cells. Located at the back of the thyroid gland and control calcium levels.

Question 23

Name the 3 layers of the adrenal cortex in order from outside to inside.

Answer 23

Zona glomerulosa
Zona fasciculata
Zona reticularis

Question 24

Describe the location of the adrenal/suprarenal gland, state whether it is exocrine or endocrine and which part secretes what.

Answer 24

Above the kidneys. Endocrine. Cortex secretes corticosteroids, medulla secretes adrenaline and noradrenaline.

Question 25

State the location of the thyroid gland, whether it is exocrine and endocrine, and its histological structure.

Answer 25

Butterfly shaped gland wrapped around trachea. Endocrine. Simple cuboidal epithelia surrounds colloid.