Linked Life Data

2246894

Source:http://linkedlifedata.com/resource/pubmed/id/2246894

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1991-1-9
pubmed:abstractText
The adaptive significance of the scrotum is unresolved after more than 60 years of debate and experimentation. The "training hypothesis" introduced here suggests that testicular descent is a mechanism for improving sperm quality. The hypothesis proposes that: (1) testicular descent decreases blood supply to maturing sperm cells, (2) sperm mitochondria respond to the resulting oxygen stress by enhancing their enzymatic machinery for oxidative metabolism, as do oxygen-stressed muscle cell mitochondria, and (3) the resulting increase in aerobic fitness of sperm cells is advantageous in inter-ejaculate competition. The hypothesis suggests that there is a quantity-quality trade-off in sperm production, where taxa with internal testes produce large volumes of low-quality sperm while taxa with scrotal testes produce smaller volumes of higher-quality sperm.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0022-5193
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
145
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
429-45
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
The evolution of the scrotum: a new hypothesis.
pubmed:affiliation
Department of Zoology, University of Washington, Seattle 98195.
pubmed:publicationType
Journal Article