In some sheep, the presence of beard is produced by an autosomal allele that is dominant in males and recessive in females. A beard female is crossed with a homozygous beardless male. One of the resulting F1 females is crossed with a beardless male. What proportion of the male and female progeny from this cross will have beard in F2 generation?

#Question id: 10366

#Unit 6. System Physiology – Plant

Cyanobacteria can fixes nitrogen in an anaerobic conditions. Which of the following statements about heterocyst which is specialized cell of blue-green algae is incorrect?

#Question id: 10367

#Unit 6. System Physiology – Plant

Cyanobcteria also fixes nitrogen under anaerobic conditions without  heterocyst where?

#Question id: 10368

#Unit 6. System Physiology – Plant

Free-living bacteria that are capable of fixing nitrogen are aerobic, facultative, or anaerobic. Some of the Aerobic nitrogen-fixing bacteria such as

#Question id: 10369

#Unit 6. System Physiology – Plant

Which type of the nitrogen-fixing bacteria are thought to maintain a low oxygen concentration (microaerobic conditions) through their high levels of respiration

#Question id: 10370

#Unit 6. System Physiology – Plant

Rhizobial genes that participate in nodule formation are called nodulation (nod) genes. Only one of the nod genes, the regulatory and constitutively expressed and regulates the transcription of the other nod genes;

#Question id: 10371

#Unit 6. System Physiology – Plant

There are three essential nod gene for every bacterial species that is−NodA, NodB and NodC, that are required for synthesizing this basic structure such as;

a) NodA is an N-acyltransferase that catalyzes the addition of a fatty acyl chain

b) NodB is a chitin-oligosaccharide synthase that links the acetyl group of the terminal nonreducing sugar

c) NodC is a chitin-oligosaccharide synthase that links N-acetyl-D-glucosamine monomers

d) NodB is a chitin-oligosaccharide deacetylase that removes the acetyl group from the terminal nonreducing sugar

e) NodC is a chitin-oligosaccharide deacetylase that removes links N-acetyl-D-glucosamine monomers

Which of the following statements about NOD Factor is incorrect?