ENVS 2210 Lecture Notes - 2018 Lecture 4 - Arthropod leg, Esophagus, Malpighian tubule system
20 Sep 2018
School
Department
Course
Professor
Functional Honey Bee Morphology
Ernesto Guzman
1. THE COLONY MEMBERS
- Known as morphological castes: worker (non-reproductive female), drone
(male) and queen (reproductive female)
2. THE EXOSKELETON
- External skeleton composed of hardened plates (made out of chitin) connected
by membranes to provide the insect with a structure and movement
- Function: provides protection, support and attachments for muscles and
organs and prevents dehydration
3. THE BODY SEGMENTS
- Three body segments: Head, thorax and abdomen, each with sub-segments
4. THE HEAD
- Contains sensory and digestive structures: Eyes, antennae and mouthparts
- Eyes: Two types; three ocelli or simple eyes, and two compound eyes
- Antennae: The bee’s “nose.” Antennae are composed of 12 segments that
contain sense organs; the sensilla (plates, pits and hairs) used to detect
odors, CO2, humidity, flavors, temperature, and air-flow.
- Mouthparts: Include the mandibles and the proboscis used for chewing-
lapping functions to ingest or manipulate solids and liquids
- Mandibles:
- Proboscis: Tube-like structures for the ingestion of liquids (5-7 mm).
Function as a feeding and tasting straw.
5. THE THORAX
- Composed of three sub-segments: prothorax, mesothorax and metathorax,
plus the propodeum (first abdominal segment). Contains structures for
locomotion and for pollen transport. Three pairs of legs, each pair
attached to each segment. Two pairs of wings attached to the last two
segments
Figure 1. The legs of the honeybee showing specialized components. Source:
Winston M.L. 1987. The Biology of the Honey Bee. Harvard Univ. Press,
Cambridge MA.
- The legs: Each composed by coxa (hip), trocanter (femur head), femur,
tibia and tarsus. At the distal part of the tarsus there are claws and a pad
(arolium).
- The first and last pairs of legs have specialized structures.
- The hair of the bees is branched to carry pollen grains
- The wings: Membranous structures. They are outgrowths of the
exoskeleton.
- The flight: Bees fly at an average speed of 24 km/h and wings beat at
about 200 cycles/sec. Longitudinal and dorso-ventral (vertical) muscles
bend the thorax (flexible exoskeleton) moving wings up and down
Document Summary
Known as morphological castes: worker (non-reproductive female), drone (male) and queen (reproductive female: the exoskeleton. External skeleton composed of hardened plates (made out of chitin) connected by membranes to provide the insect with a structure and movement. Function: provides protection, support and attachments for muscles and organs and prevents dehydration: the body segments. Three body segments: head, thorax and abdomen, each with sub-segments: the head. Contains sensory and digestive structures: eyes, antennae and mouthparts. Eyes: two types; three ocelli or simple eyes, and two compound eyes. Antennae: the bee"s nose. antennae are composed of 12 segments that contain sense organs; the sensilla (plates, pits and hairs) used to detect odors, co2, humidity, flavors, temperature, and air-flow. Mouthparts: include the mandibles and the proboscis used for chewing- lapping functions to ingest or manipulate solids and liquids. Proboscis: tube-like structures for the ingestion of liquids (5-7 mm). Function as a feeding and tasting straw: the thorax.
