Lipids as pigments in plants and bird feathers.

Birds acquire the pigments that color their feathers red or yellow by eating plant materials that contain carotenoid pigments, such as canthaxanthin and zeaxanthin.

The differences in pigmentation between male and female birds are the result of differences in intestinal uptake and processing of carotenoids.

TLS Online TPP Program

#Id: 8132

#XL - Q Biochemistry

Lipids as pigments in plants and bird feathers.

Birds acquire the pigments that color their feathers red or yellow by eating plant materials that contain carotenoid pigments, such as canthaxanthin and zeaxanthin.

The differences in pigmentation between male and female birds are the result of differences in intestinal uptake and processing of carotenoids.

TLS Online TPP Program

#Id: 8132

#XL - T Zoology

Lipids as pigments in plants and bird feathers.

Birds acquire the pigments that color their feathers red or yellow by eating plant materials that contain carotenoid pigments, such as canthaxanthin and zeaxanthin.

The differences in pigmentation between male and female birds are the result of differences in intestinal uptake and processing of carotenoids.

TLS Online TPP Program

#Id: 9614

#XL - T Zoology

Upon insulin binding, the extracellular domain is converted into a T-shaped conformation that brings the transmembrane domains together.

TLS Online TPP Program

#Id: 9615

#XL - T Zoology

Four related EGF receptors participate in signaling by the many members of EGF family :

In the mouse - Erb-B1, 2, 3, and 4

In humans - HER 1, 2, 3, and 4

TLS Online TPP Program

#Id: 9616

#XL - T Zoology

Homodimerization

HER1 directly binds EGF which leads to formation of a homodimer of the HER1 extracellular domain

TLS Online TPP Program

#Id: 9617

#XL - T Zoology

TLS Online TPP Program

#Id: 9618

#XL - T Zoology

Neuregulins 1, 2, 3, and 4, bind to HER4 that, like HER1, can also form homodimers.

TLS Online TPP Program

#Id: 9619

#XL - T Zoology

HER2 (mouse Erb-B2), cannot bind any ligand, it can form a heterodimer with ligand-activated HER1, HER3, or HER4 (Erb-B1, 3, or 4)