In which structure does diffusion of oxygen to capillaries not play a major role?

#Question id: 23658

#Unit 13. Methods in Biology

How many recombinant clones must be screened in order to be 99% certain that a particular gene is found in a YAC library of human DNA where the average size of an insert is 500 kbp? The human genome size is about 3.2 x 10⁶ kbp. 

#Question id: 1601

#Unit 4. Cell Communication and Cell Signaling

Cytotoxin T cells express

#Question id: 10243

#Unit 10. Ecological Principles

A group of species that potentially compete with one other for a resource, such as insect- eating birds, is called a

#Question id: 11653

#Unit 10. Ecological Principles

Given some characteristics of the climax community

i) Tolerate its own reactions

ii) Tends to become mesic

iii) Less stable

iv) Complex stratification

v) Simple food web

vi) Less mutualism

vii) Gross production is equals to community respiration

viii) Net community production is zero

Which of the following combination shows the characteristics of climax community?

#Question id: 7099

#Unit 5. Developmental Biology

A fate map of a Xenopus blastula, just before gastrulation begins, shows that the top portion of the embryo will become ectoderm (skin and nerve), the central portion will become mesoderm (bone, muscle, and blood), and the lowest portion will become endoderm (gut). How is it that the endoderm and mesoderm, shown on the outside in the fate map, end up on the inside in the embryo after gastrulation?