CBSE Questions for Class 11 Medical Biology Biological Classification Quiz 11 - MCQExams.com

• In Rhizopus, the male (+) and female (-) gametangia fuse and the gametangial copulation leads to the formation of a zygospore.
•  On germination, the innermost layer comes out after cracking the outer walls and produces a promycelium. With further develop­ment, the promycelium is differentiated into a lower stalk-like sporangiophore and an upper spherical sporangium. Hence, the Zygospore of Rhizopus develops into Promycelium.
• So, the correct answer is "Promycelium
  

• Letharia vulpina is toxic to mammals due to the yellow pigment vulpinic acid.
• It has been used historically as a poison for wolves and foxes.  Hence, A harmful lichen is Letharia.
• So, the correct answer is "Letharia'.

Correct Option: A

Explanation:

• Zygospores are the asexual spores produced in the zygomycetes.
• Zygospores are strong and resistant spores generated by the fusing of two nuclei of two haploid cells and the formation of gametangia to produce zygote and then the zygospore.
• In gametangial copulation, the male and female gametangia come into close contact with each other but do not fuse.
• A fertilization tube is produced where male gametangium enters female gametangium and male gamete goes through.
• Two gametangia or their protoplasts unite to form a zygospore.

Hence, zygospore is formed from gamentangial copulation.

• Natural classification is based on the complete morphological characters of stem, root, leaves, flowers etc. Bentham and Hooker's classification is based on these characters hence it is an example of to be the natural system.
  
• Aristotle and Theophrastus used simple and observable traits for classification.
• Darwin and Wallace were associated with theories related to evolution.
  
• Engler and Prantl presented the evolutionary system of classification
  

• Renales are the most primitive living angiosperms hence placing them, in the beginning, is the merit of Bentham and Hooker's system.

• Aristotle was a Greek philosopher during the Classical period in Ancient Greece, the founder of the Lyceum and the Peripatetic school of philosophy and Aristotelian tradition. 
• Aristotle was born in 384 B.C. in Stagira in northern Greece.
  
• Aristotle divided animals into Aniama( "those without RBC") and enaima( "those with blood). Anaima examples invertebrates and Enaima examples vertebrates
  
• So, the correct answer is 'Anaima and enaima'.

1. Atrichous: Flagella absent
2. Monotrichous: A single flagellum occurs at or near one end of bacterium.
3. Amphitrichous: A flagellum at each of the two ends.
4. Cephalotrichous: A group or tuft of flagella is found at one end.
5. Lophotrichous: A tuft or group of flagella at each of the two ends or poles.
6. Peritrichous: A number of flagella are distributed all over the surface.

• Lichens are widely used as environmental indicators or bio-indicators. If the air is clean, shrubby, hairy and leafy, the lichens become abundant. 
• Only a few lichen species can tolerate quite high levels of pollution.

• Chargaff's rules states that DNA from any cell of all organisms should have a 1:1 ratio (base Pair Rule) of pyrimidine and purine bases and, more specifically, that the amount of guanine is equal to cytosine and the amount of adenine is equal to thymine, such that their ratio remains 1.
  
• Coliphage ϕ×174, Polio virus and Tobacco mosaic virus contain single stranded RNA as their genetic material, hence, chargaff's rule is not applicable.