spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Heinrich, B
Right arrow Search for Related Content
PubMed
Right arrow Articles by Heinrich, B
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

Journal of Experimental Biology, Vol 64, Issue 3 561-585, Copyright © 1976 by Company of Biologists

JOURNAL ARTICLES

Heat exchange in relation to blood flow between thorax and abdomen in bumblebees

B Heinrich

1. The narrow passage within the petiole between thorax and abdomen is anatomically constructed so that counter-current exchange should retain heat in the thorax despite blood flow to and from the cool abdomen. 2. However, the counter-current heat exchanger can be physiologically circumvented. Exogenously heated bumblebees prevented overheating of the thorax by shunting heat into the abdomen. They also regurgitated fluid, which helped to reduce head temperature but had little effect on thoracic temperature. 3. Temperature increases in the ventrum of the abdomen occurred in steps exactly coinciding with the beats of the ventral diaphragm, and with the abdominal 'ventilatory' pumping movements when these were present. The ability to prevent overheating of the thorax by transport of heat to the abdomen was abolished when the heart was made inoprative. 4. At low thoracic temperatures the ventral diaphragm beat at a wide range or rates and with varying interbeat intervals, while the heart beat at a high frequency relative to the ventral diaphragm, but at a very low amplitude. However, when thoracic temperature exceeded 43 degrees C the amplitudes of both were high, and the interbeat intervals as well as the beating frequencies of the two pulsatile organs became identical in any one bee. Furthermore, heated bees engaged in vigorous abdominal pumping at the same frequency as that of their heart and ventral diaphragm pulsations. 5. The results indicate that the anatomical counter-current heat exchanger is reduced or eliminated during heat stress by 'chopping' the blood flow into pulses, and the blood pulses are shunted through the petiole alternately by way of a switch mechanism.
Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?


This article has been cited by other articles:


Home page
 J. Exp. Biol.Home page
W. A. Woods Jr, B. Heinrich, and R. D. Stevenson
Honeybee flight metabolic rate: does it depend upon air temperature?
J. Exp. Biol., March 15, 2005; 208(6): 1161 - 1173.
[Abstract] [Full Text] [PDF]

Home page
 J. Exp. Biol.Home page
P. M. Koladich, S. S. Tobe, and J. N. McNeil
Enhanced haemolymph circulation by insect ventral nerve cord: hormonal control by Pseudaletia unipuncta allatotropin and serotonin
J. Exp. Biol., October 15, 2002; 205(20): 3123 - 3131.
[Abstract] [Full Text] [PDF]

Home page
 ScienceHome page
B. HEINRICH
Keeping a Cool Head: Honeybee Thermoregulation
Science, September 21, 1979; 205(4412): 1269 - 1271.
[Abstract] [PDF]


© The Company of Biologists Ltd 1976