5.11 Reproductive system of Q and D and the production of sperm and eggs

Question 1

What happens to the ovaries of a queen after mating?

Answer 1

The ovaries increase in size after mating when eggs or ova are produced.

Question 2

What is the structure of each ovary in a queen?

Answer 2

Each ovary consists of between 150-180 ovarioles, which are tubes within which the eggs develop.

Question 3

What do ovarioles lead into?

Answer 3

Ovarioles lead into lateral oviducts, which then merge to form the median or common oviduct.

Question 4

What is the function of the median oviduct?

Answer 4

The median oviduct serves both ovaries and passes the valvefold close to the entrance to the spermatheca.

Question 5

What does the spermatheca hold?

Answer 5

The spermatheca holds the sperm from the drones.

Question 6

What is the role of the spermathecal gland?

Answer 6

The spermathecal gland nourishes the sperm.

Question 7

How are eggs developed in the ovarioles?

Answer 7

Eggs develop from germinal cells, forming around 48 trophocytes and an oocyte through meiosis.

Question 8

What surrounds the whole ovum or egg?

Answer 8

The whole ovum or egg is surrounded by follicle cells.

Question 9

What happens to trophocytes as the egg develops?

Answer 9

The trophocytes absorb nutrients from the haemolymph and pass these to the oocyte, which increases in size.

Question 10

What occurs when the egg is about to be laid?

Answer 10

The egg can pass through the reproductive system without being fertilised or can be fertilised by sperm from the spermathecal gland.

Question 11

What is the process of fertilisation in the egg?

Answer 11

The egg passes over the muscular valvefold, which presses the egg against the entrance of the spermathecal duct.

Question 12

How many ovarioles do worker bees possess?

Answer 12

A worker possesses ovaries made of around 2-12 ovarioles.

Question 13

What is the role of the drone’s testes?

Answer 13

The role of the drone’s testes is to produce sperm cells.

Question 14

What is the process of sperm production in drones?

Answer 14

Sperm are produced in tubes starting as germ cells, dividing to produce spermatogonia, which form spermatocytes and then spermatids.

Question 15

What happens to sperm after they mature in drones?

Answer 15

Once mature, sperm move down the muscular vas deferens tubes into the seminal vesicles in preparation for mating.

Question 16

What occurs during mating in drones?

Answer 16

Sperm travel through the ejaculatory duct, passing mucus glands that add mucus to the sperm.

Question 17

What is the function of the endophallus bulb during mating?

Answer 17

The endophallus bulb everts through the phallotreme and enters the queen’s bursa copulatrix.

Question 18

What is the fate of sperm after entering the queen?

Answer 18

Sperm move to the spermatheca and reside there until needed, with around 5-6 million sperm stored after multiple matings.

Question 19

What are the ovaries?

Answer 19

Two, one each side of the abdomen situated above the digestive system. Made up of 150-180 egg tubes known as ovarioles which produce the eggs.

Question 20

What are oviducts?

Answer 20

One tube leading from each ovary down which the eggs pass after leaving the ovary. These are lateral oviducts which join together to form the median oviduct, a very short tube that leads to the vagina.

Question 21

What is the vagina?

Answer 21

A somewhat wider tube, rather oval in shape, ending in a narrow slit. There is another tube that enters the vagina on its dorsal side. Immediately below this second opening, on the floor of the vagina is a fold of tissue called the valvefold.

Question 22

What is the function of the valvefold?

Answer 22

The queen’s deployment of the valvefold determines whether the egg passing will be fertilised or not.

Question 23

What is the bursa copulatrix?

Answer 23

This is a wide cavity opening to the outside of the body. The sting is loosely anchored to its top. On either side are two swellings called the lateral pouches.

Question 24

What is the spermatheca?

Answer 24

A round structure situated above the vagina. There is a short spermathecal duct leading from it which opens into the dorsal wall of the vagina.

Question 25

What is the function of the spermathecal duct?

Answer 25

There is a valve and pump within the duct that controls the release of sperm to the vagina.

Question 26

What do the spermathecal glands do?

Answer 26

These glands provide nourishment to the 5.5-6 million sperm stored in the spermatheca after mating.

Question 27

What are the testes?

Answer 27

The two testes are the structures that produce sperm.

Question 28

When do the testes reach their peak size?

Answer 28

They reach their peak size in the pupal stage before the drone emerges.

Question 29

What happens to the testes after the drone emerges?

Answer 29

They gradually shrink over the next 12 days as the drone reaches full sexual maturity.

Question 30

What is the vas deferens?

Answer 30

Short curly tubes with muscular walls that lead from the testis to the seminal vesicle.

Question 31

What is the structure and function of the seminal vesicle?

Answer 31

Large muscular walled sausage-shaped structures where spermatozoa take their final form and are nourished by a fluid produced by the cells.

Question 32

What are mucus glands?

Answer 32

Large fat glands that form a U-shape and lie below the smaller seminal vesicles, not involved with sperm production or storage.

Question 33

What is the function of the lining of muscular cells in mucus glands?

Answer 33

They produce a liquid that sets into a thick mass on contact with air.

Question 34

What connects the seminal vesicles to the mucus glands?

Answer 34

A short tube from each of the seminal vesicles opens into the base of the mucus glands.

Question 35

What is the ejaculatory duct?

Answer 35

A long tube from the inner side of the base of the U formed by the mucus glands.

Question 36

Where does the ejaculatory duct open?

Answer 36

The duct opens into the bulb of the endophallus.

Question 37

What is the bulb of the endophallus?

Answer 37

A very swollen structure with various plates of cuticle on its surface.

Question 38

What happens during mating involving the endophallus?

Answer 38

The drone inverts his endophallus into the queen’s open sting chamber, leading to ejaculation.

Question 39

What occurs to the drone during mating?

Answer 39

The drone becomes paralysed, flips backwards, and ejaculation results from the pressure of the drone’s haemolymph as the abdomen contracts.

Question 40

What are the fine tubes in the testis called?

Answer 40

Each testis is made up of a series of very fine tubes that open in the vas deferens.

Question 41

Where are the original germ cells housed in the testis?

Answer 41

At the top of each tube is the germarium where the original germ cells are housed.

Question 42

What do germ cells divide to form?

Answer 42

The cells divide to form spermatogonia.

Question 43

What are groups of spermatogonia enclosed in a membrane called?

Answer 43

As these move down the tube, they form groups enclosed in a membrane and are called spermatocytes.

Question 44

What do spermatocytes grow into after dividing?

Answer 44

The spermatocytes grow in size and then divide (the abortive meiotic division) to produce spermatids.

Question 45

How do spermatids change shape?

Answer 45

At this point, they change their shape to become long thin cells with a swollen ‘head’ end containing the nucleus and a long ‘tail’. Now fully formed spermatozoa.

Question 46

Where do spermatozoa pass after formation?

Answer 46

The spermatozoa pass through the vas deferens into the seminal vesicle where they are stored.

Question 47

What is the function of the seminal vesicles?

Answer 47

The vesicles have muscular walls lined internally by cells that produce a fluid to nourish the sperms until they are required.

Question 48

Describe the production of the honey bee egg.

Answer 48

Describe how sperm is produced and stored 7 * Each testis is made up of a series of very fine tubes that open in the vas deferens. * At the top of each tube is the germarium where the original germ cells are housed. * The cells divide to form spermatogonia. * As these move down the tube they form groups enclosed in a membrane and are called spermatocytes. * The spermatocytes grow in size and then divide (the abortive meiotic division) to produce spermatids. * At this point they change their shape. They become long thin cells with a swollen ‘head’ end containing the nucleus and a long ‘tail’. Now fully formed spermatozoa. * The spermatozoa pass through the vas deferens ito the seminal vesicle where they are stored. * The vesicles have muscular walls lined internally by cells that produces a fluid to nourish. the sperms until they are required.