The mussel Mytilus edulis thrives in saline habitats, in both the highly salty seawater of tidal zones and the less salty estuaries. This results in two kinds of populations: one adapted to the higher salt concentrations of the tidal zone, and one adapted to the lower salt concentrations of the estuary. It has been found that the more salt-tolerant populations have high frequencies of an allele that produces an enzyme involved in maintaining osmotic equilibrium. Conversely, estuarine mussels having the same enzyme seem to be disfavoured and have a much higher death rate than mussels without the allele. Adult estuarine populations do have lower frequencies of this allele. Each spring, large numbers of larvae from  the salty habitats pour into the estuaries.

The invasion of the seawater larvae would be expected to facilitate change in the genetic structure of the estuarine population by a process called

#Question id: 9578

#Unit 10. Ecological Principles

#Question id: 9579

#Unit 10. Ecological Principles

#Question id: 9580

#Unit 6. System Physiology – Plant

Many Antenna Complexes Have a common structural motif In all eukaryotic photosynthetic organisms that contain both chlorophyll a and chlorophyll b, the most abundant antenna proteins are members of a large family of structurally related proteins, some of these proteins are associated with PSI and PSII such as LHCI and LHCII , Select the incorrect one regarding LHC complexes;

#Question id: 9581

#Unit 6. System Physiology – Plant

These four Photosystem II, Cytochrome b6 f, Photosystem I and ATP synthase integral membrane complexes are vectorially oriented in the thylakoid membrane to function as follows, find out the incorrect statements;

#Question id: 9582

#Unit 6. System Physiology – Plant

Electrons ejected from chlorophyll travel through a series of electron carriers organized in the “Z Scheme” shows a current version of the Z scheme, in which all the electron carriers known to function in electron flow from H2O to NADP Presented in the following sequence;

a.) P680 reduce by Yz has received electrons from oxidation of water P680→P680*→pheophytin→ plastoquinones→ cytochrome b6 f complex→ plastocyanin→ in turn reduces (PSI) P700+

b.) P700+→ P700*→ membrane-bound iron–sulfur proteins → A0→ A1 → flavoprotein ferredoxin–NADP reductase (FNR) soluble → ferredoxin(Fd) → NADP+ to NADPH

c.) P700+→ P700*→ A0→ A1→ membrane-bound iron–sulfur proteins→ ferredoxin(Fd)→ soluble flavoprotein ferredoxin–NADP reductase (FNR)→ NADP+ to NADPH

d.) P680 reduce by Yz has received electrons from oxidation of water P680→P680*→ plastoquinones → pheophytin → cytochrome b6 f complex→ plastocyanin→ in turn reduces (PSI) P700+

Which one of the following combinations is correct?

#Question id: 9583

#Unit 6. System Physiology – Plant

 A mechanism known as the Q cycle accounts for most of the observations in which structure and reactions of plastoquinone that operate in,