Vulnerability to extinction can be linked to species following characteristics. Which of the following statement are correct?

 A. Rare species are more prone to extinction than common ones.

 B. Species that are capable of migrating between fragments of habitat, such as between mainland areas and islands, may be more resistant to extinction

 C. Organisms that are specialists are more likely to go extinct

 D. Species with naturally long life spans may be more likely to become extinct

TLS Online TPP Program

#Question id: 13122

#Unit 2. Cellular Organization

Choose the incorrect?

1- COPI vesicles transport proteins from the rough ER to the cis -Golgi; COPII vesicles transport proteins in the reverse s Direction.

2- The KDEL receptor binds more tightly to its ligand ar low pH, and it is thought that the receptor is able to bind KDEL peptides in the cis-Golgi but to release these peptides in the ER because the pH of the Golgi is slightly lower than that of the ER.

3- The KDEL sorting signal is recognized and bound by the KDEL receptor, a transmembrane protein found primarily on small transport vesicles shuttling between the ER and the cis -Golgi and on the cis-Golgi reticulum.

TLS Online TPP Program

#Question id: 13121

#Unit 2. Cellular Organization

--------- act as a nuclear export factor and directs the associated mRNP to the central channel of the NPC by transiently interacting with FG- nucleoporins.

TLS Online TPP Program

#Question id: 13120

#Unit 2. Cellular Organization

Match the correct one?

Target organelle	Location of sequence within protein	Removal of sequence	Nature of sequence
1- ER	i- N- terminal	a- yes	P- Core of 6-12 hydrophobic aa often preceded by one or more basic ammo acids (Arg, Lys)
2-Mtochrondria matrix	ii- N- terminal	b- yes	Q- Multiple different kinds;  rich in Lys and Arg residues
3-Chloroplast stroma	iii- N- terminal	c- no	R- Lys and arg one side and other side hydrophobic aa
4-Nucleus	iv-varies	d- yes	S- Generally rich in ser and thr, poor in glu and asp

TLS Online TPP Program

#Question id: 13119

#Unit 2. Cellular Organization

Ions, small metabolites, and globular proteins up to about ---------- can diffuse passively through the central aqueous region of the nuclear pore complex.

TLS Online TPP Program

#Question id: 2059

#Unit 2. Cellular Organization

For a protein to be an integral membrane protein, it would have to be:

TLS Online TPP Program

#Question id: 2060

#Unit 2. Cellular Organization

An animal cell lacking carbohydrates on the external surface of its plasma membrane would likely be impaired in which function?