Bee Anatomy with Diagrams: Internal, External Structure

Bees are a group of flying insects from the order Hymenoptera. These tiny representatives of the fauna, characterized by short life, work all day long to feed their large family, thereby playing an important role in the pollination of flowering plants, as they collect nectar and pollen. Let’s take a closer look at the bee anatomy.

bee anatomy

Table of Contents

Bee anatomy: General characteristics of bee

In total, there are about 21 thousand species and 520 genera of bees. They are found on 6 continents. Nature has designed them so that they are able to feed on nectar and pollen, making them the main pollinators of flowering plants. Bees draw in nectar, which is a source of energy, with the help of a long proboscis, and finds it and pollen thanks to their antennae. This is their main organ of smell. All individuals of the bee family have one pair of antennae. They consist of segments, the number of which depends on the sex of the individual. Do you want to get more bee knowledge?

While in general about bee anatomy. Bees always have two pairs of wings, one pair of which (front) is larger than the second (back). Everyone knows well what color a bee is: black with yellow transverse stripes, but the body length varies, depending on the species, within 2.1–39 mm. The smallest size is dwarf bees, the largest are representatives of the species Megachile pluto, living in Indonesia. In the cycle of bee development, the following stages are distinguished: egg, larva, pupa, adult. The egg is laid in a cell.

The type of newborn individual (womb, drone, worker) depends on which part of the mother liquor the egg will be placed in. The egg laid by the uterus is located vertically in the cell. When fertilization occurs, the embryo will begin to develop, the position of the egg in the cell will change (it will gradually tilt to the side). After 68–76 hours, necessary for the development of all organs of the embryo, the egg will lie horizontally at the bottom of the cell.

At this point, the bees place food next to the egg, which will contribute to the destruction of the egg shell and the appearance of a tiny larval worm from it. The bees are constantly adding food, so the larva is surrounded by food, which is constantly mixed due to the movements of the worm. The newly born larva is only 1.6 mm long and transparent. By the end of the first day of her life, she already reaches 2.6 mm and her body becomes less transparent.

Important! After sealing, the larva of the future worker bee loses weight, while the future queen, on the contrary, gains. Because of this, the nurse bees gnaw the lid in advance and gnaw the queen cocoon to make it easier to leave it.

On the third day of life, the larva will fill the entire bottom of the cell and have a matte color. From this moment on, different larvae begin to feed differently. So, the diet of worker bees from the first day of life consists of milk, then it is replaced with honey and bee bread. Future queens are fed exclusively with milk alone. Drones are also fed with milk, but even more satisfying. During 5 (queen), 6 (worker) and 7 (drone) days, the larva molts 4 times. At the end of the last day, the nurse bees seal the cells with the larvae.

The pupation process begins. How many days it will take also depends on the type of larva. Until the pupa has turned into an adult insect, the molting process takes place a couple more times, and after the last drop of the old shell, the young insect gnaws through the lid and crawls out. In total, it takes 20 days to develop a worker bee, 16 days for a queen, and 24 days for a drone.

bee anatomy diagram

Let’s look at the bee anatomy diagram with labeling.

bee anatomy diagram

1. Tongue.2. The mouth of the submandibular gland.3. Maxillas.4. Mandibles.5. Upper lip.6. Lower lip.7. Maxillary salivary gland.8. Mandibular salivary gland.9. Throat.10. Pharyngeal (allotrophic) gland.11. Brain.12. Simple eyes.13. Labial salivary gland.14. Longitudinal flight muscle.15. Fragma.16. Front fender.17. Rear wing.18. Heart.19. Spiracles.20. Air bag.21. Midgut (stomach).22. Heart valves.23. Small intestine.24. Smelly gland.25. Abdominal glands.26. Large intestine.27. Anus.28. Sting.29. Poison gland reservoir.30. Sled sting.31. Large poisonous gland.32. Small poisonous gland.33. Seminal vesicle.34. Wax glands.35. Abdominal nerve chain.36. Cardiac valve.37. Valve bell.38. Valve inlet.39. Honey goiter.40. Aorta.41. Esophagus.42. Nervous cord.43. Labium.44. Back leg.

The structure of the legs

a. Basin ( coxa ).b. Swivel ( trochanter ).c. Thigh ( femora ).d. Drumstick ( tibia ) with pollen Foot ( tarsus ).

Bee anatomy: External structure of Bee

First, in bee anatomy, we will look at the external structure of the bee. The body of the bee is segmented. It can be divided into such parts: head, thoracic region, abdomen. The whole body is covered with hairs, which are the organ of touch. In addition, they protect the upper body from pollution.

Bee Head

The head is protected by a thick layer of chitin, under which is the brain. Its size depends on the type of bee. The drone has more of it than the rest of the individuals. The size and shape of the head also depend on the work duties of the insect. In the uterus, it is rounded, the eyes are shifted to the frontal part. In workers, it is triangular, the usual eyes are located on the crown, in drones it is rounded, and the compound eyes go around the head and converge on the crown. Simple ones are shifted towards the forehead.

Schematic illustration of the head of a bee (the head of the uterus (A), the worker bee (B) and the drone (C): 1 – simple eyes, 2 – compound eyes, 3 – antennae, a – main segment, b – flagellum, 4 – upper lip, 5 – upper jaw, 6 – proboscis):

Bee Head

In the wide part of the head on the sides there are 2 large fixed compound eyes. Between them, in the upper part, there are 3 ordinary eyes. The space between them is dotted with long and dense hairs. In the rest of the head they are shorter. Antennae are located in front, above the upper lip. In females, they are divided into 11 segments, in males – into 12.

All of them are connected by membranes, which makes the mustache very mobile. In the cavity of each antennae there is a nerve that goes to the olfactory lobe of the brain. The outer shell of the antennae is the organ of touch and smell. Below is a proboscis, consisting of two lower jaws and a lower lip, capable of closing and dismembering.

Did you know? The speed of the bee is about 65 km/h. If it flies loaded, then this value will decrease to 20 – 30 km / h.

When they move, the trunk takes the form of a tube, with the help of which the insect collects liquid food. The tongue licks off solid food. Only worker bees have such a functional proboscis. For the rest, it is shorter, and the oral apparatus has lost its direct purpose. The upper jaws are well developed, as they perform a gnawing function.

With their help, the insect kneads the wax when it builds cells, and when it goes to get food, it removes pollen from the stamens with them. The mandibles and lips help to lick and suck out the nectar. Because of this, the bee’s mouthparts are of the gnawing-sucking type.

Bee Breast

Inside the thoracic region are the muscles responsible for all movements of the insect. It consists of three rings and one segment from the abdomen. The smallest ring is connected to the head through a thin chitinous film, which allows the latter to make free movements. The middle ring acts as a frame. Attached to it is the front pair of wings. The rear pair of wings is attached to the last ring. The total number of wings is 4. Each ring has one pair of legs and spiracles through which air enters the body.

Structure of Bee wings

The wings are a thin elastic plate with veins (hardened hollow tubes). When a bee flies, both pairs of wings spread out, forming a single plane, and fastened together with small hooks. When landing, the hooks are detached and the wings are folded along the body, with the front larger wing covering the rear one. They are driven by the pectoral muscles. In flight, the insect performs 200-250 wing beats per second.

Important! In honey bees, the front pair of legs is shorter than the others, but more mobile.

Abdomen of Bee

Has 6 rings. Each ring is divided into tergite (dorsal half rings) and sternite (ventral half rings). Between themselves, they are connected by soft membranes, which allows each part to move freely. This allows the abdomen to grow in breadth and length if needed. The main internal organs of the insect are hidden behind the abdomen.

Bee legs

The legs of the bee are multifunctional. They support the body, with their help the bee moves, and also cleanses the body. In addition, in working family members, the legs help collect pollen and form wax balls. Each bee has 3 pairs of legs, consisting of 5 segments connected movably. The front legs have brushes that allow the insect to clean the eyes, mouth and antennae, and also help to scrape pollen from the body. The middle legs also take part in the removal of pollen.

They are covered with a large number of small hairs, which makes it possible to sweep pollen well. The hind limbs are as well mobile as the front ones. On them, on the outside of the lower leg, there is a basket. In it, the insect forms an obnozhka, which will be transferred to the hive. Only working individuals have such a complex structure of the limbs. For the rest of the inhabitants of the hive, they are simpler.

bee anatomy: Internal structure of Bee

The bee anatomy of the internal organs is adapted to their main task the production of honey.

Bee circulatory system

The circulatory system of a bee is not closed, but the blood always circulates in a certain direction. This is achieved through the coordinated work of the heart, aorta, abdominal and dorsal diaphragm. The heart is like a long tube and is located along the back. In the chest is the aorta, which delivers blood to the head. The entire tube is divided into 5 chambers connected through septa-valves that allow blood to flow in a certain direction (from the abdomen to the head).

The heart beats 60-70 times per minute at rest. Flight increases the pulse rate to 150. The dorsal and abdominal diaphragms are also part of the circulatory system. They control the flow of blood into the body. Blood moves to the limbs, antennae and wings thanks to the bubbles located at the base of these parts of the body.

Did you know?

When a bee stings, it releases 0.3 – 0.8 mg of poison. Its amount will depend on the season and the age of the insect. A dose of 0.2 g is lethal to humans. This amount of poison can be obtained from 500 – 1000 stings.

Bee Nervous system

The nervous system bee anatomy is divided into three sections: central, peripheral and sympathetic. The central one includes the brain and the ventral chain of nerves, which replaces the spinal cord. The frontal node is the beginning of the sympathetic department responsible for the functioning of the digestive, circulatory and respiratory systems. The brain, as the main node of the nervous system, contains the bulk of the neurons.

Their greatest number is in the visual lobe and mushroom body. As mentioned earlier, the size of the brain depends on the functions of the bee. In drones, it is the largest, but at the same time, the working individual has the most developed departments.

A nerve cell (neuron) is the main structural unit of the nervous system. It has one long process (without branches) that transmits nerve impulses, and a branched process that can receive signals from an unbranched process and other neurons and transmit it by an electrical signal to its neuron. It turns out that the first process plays the role of an output channel for transmitting information, and the second one plays the role of an input channel.

Bee Respiratory system

The structural features of the respiratory system of an insect are such that air enters the body through spiracles, which are holes in the cuticle. Three pairs of spiracles are located on the thoracic region, 6 pairs – on the abdomen. Passing through the spiracles, the air is cleared of dust and collected in bags. This air cannot escape back due to the fact that the spiracles have valves.

From the bags, the air is carried through the trachea through tiny annular branches to all body systems. The body leaves the air only through the abdominal spiracles. Large first spiracles are reliably protected by thick hair, but ticks can still get into them and cause the development of a disease called acarapidosis.

Important! Usually the old queen leaves the colony with a swarm, and the young one remains in the hive.

Bee reproductive system

In bees, there are two types of females: the uterus and the working individual, but only the first type is capable of producing high-quality offspring. Usually there is only one queen for the whole bee colony. In working individuals, the genital organs are highly reproduced. The ovaries and oviducts do not have developed tubules. They begin to develop under certain conditions (the uterus died and the worker bees changed their diet).

This will allow the females to produce eggs, but since they lack a receptacle, the eggs will be unfertilized and only males will emerge from them. In the uterus, the ovary has about 150 tubes, in which there is one mature egg. The ovaries and vagina are connected by a paired oviduct.

The seminal receptacle is connected to the narrow part of the vagina through the canal. The channel acts as a kind of dispenser, which at the right time passes several spermatozoa. If fertilization occurs, then a working individual will appear from the egg, if not, a drone.

In a section, the reproductive system of the uterus looks like this (1 – ovary, 2 – paired oviduct, 3 – seminal receptacle, 4 – accessory gland of the seminal receptacle, 5 – vagina, 6 – reservoir of the large poisonous gland, 7 – small poisonous gland, 8 – sting):

Bee reproductive system

The structure and functions of Bee sting

The sting is a means of protection, defense of the bee, as well as an aid in laying eggs. Only females have it. Looking like a needle, the sting is a modified ovipositor. It is located at the end of the abdomen and is covered by its extreme segments. Three systems of glands approach it: lubricating, small and large poisonous. The surface of the sting itself is similar to a saw, which allows it to get stuck in the tissues of the enemy.

But, unfortunately, because of this, the bee loses it and dies. The longer the sting is in the “victim”, the more poison from the tank will enter the body and the more it will harm it. Poison is a colorless liquid with a distinct odor and bitter taste. It crystallizes rapidly in air.

Important! The productivity of the uterus is highest in the first year of life and slightly less at the beginning of the second. She is able to lay about 1500 – 2000 eggs per day per season.

The structure of the sting for bee anatomy is shown in the figure below, where

The structure and functions of Bee sting
  • 1 is a sled,
  • 2 is the processes of the sled,
  • 3 is an oblong plate,
  • 4 is a palp,
  • 5 is a triangular plate,
  • 6 are stilettos,
  • 7 is a square plate,
  • The muscles of the sting,
  • a large poisonous gland,
  • a reservoir of a poisonous gland,
  • a small poisonous gland:

Bee Swarming Features

Swarming is a natural process of dividing a bee colony. This happens when the bee family increases to such a size that the milk secreted by the queen is not enough to feed all those in need.

The following moments precede swarming:

  1. Arrangement of cells and laying eggs in them, from which queens will appear.
  2. The uterus stops producing eggs. Because of this, its size is significantly reduced.
  3. Honeycombs are not built, nectar and pollen are practically not collected.

When the nurse bees seal the cells with future queens, the colony can begin to divide. If the weather is good (still, warm), then in the morning the next day after the sealing procedure, with a characteristic hum and a mouth full of honey, the bees fly out of the hive. Usually, the queen leaves it first and then waits for all the other members of the swarm to fly out.

They circle around the hive for some time in search of a queen. Seeing her, they surround and “stick around” a tree branch or other object. After a certain period of time (depending on weather conditions), the swarm moves to a new place, which is discovered by scout bees. After the swarm leaves the hive, about half of the previous number of insects remains in it, as well as many cells with larvae.

Reasons for swarming:

  • a large number of nurse bees;
  • the hive is small and stuffy in it;
  • in summer, insects were unable to collect nectar and pollen.

The lifespan of bees depends on how strong the family is. This indicator is determined by the fertility of the uterus and, accordingly, by the number of livestock. If the family is large, then the working individual can live for about 5-7 weeks. In the weak – an average of 4 weeks. A working individual of a honey bee lives 122–152 days in winter. But the duration of life can be increased by the bees themselves due to certain circumstances.

For example, if the uterus suddenly disappeared, then some individuals can live 150–200 days longer. The impetus for an increase in life expectancy may be preparation for swarming, wintering. Those who were able to overwinter live for about 7 months and take another month to work for the benefit of the colony.

Affects the life expectancy and working capacity of the family. Alone, the uterus can live no more than 2-3 days, if there are about 20 working individuals around it, then 3 weeks, and if it is surrounded by a family, 5 years. Drones live 3-6 months and usually only during the warm season.

As you can see, the bee is a unique living organism, for the study of which a separate science of apiology was created. Despite this, this insect remains unexplored to the end. Scientists have yet to understand many interesting aspects of the honey bee anatomy and physiology and other insects.