Biology - Online Test
Q1. The exchange of gases in :
i. the alveoli that lowers the of blood and raises its is external respiration
ii. the tissues that lowers the of blood and raises its is internal respiration
i. the alveoli that lowers the of blood and raises its is external respiration
ii. the tissues that lowers the of blood and raises its is internal respiration
Answer : Option D
Explaination / Solution:
In the alveoli, there is high , low , lesser H+ concentration and lower temperature,
Q2. Tissue culture technique was first performed successfully by
Answer : Option B
Explaination / Solution:
plant tissue culture is the technique of in vitro maintaining and growing cells, tissue or organs in nutrient medium. Tissue culture technique was first performed successfully by White in 1932.
Q3. How many species in the world are facing threat of extinction?
Answer : Option B
Explaination / Solution:
Nearly 700 species have become extinctin recent times and more than 15,500 species (of which > 650 are from India) which includes amphibians, gymnosperms, reptiles, birds and mammals etc. currently face the threat of extinction.
The causes of high extinction rates at present include habitat (particularly forests) lossand fragmentation, over-exploitation, biological invasions andco-extinctions.
Q4. Which of the following is not matched correctly :
Answer : Option A
Explaination / Solution:
Adrenal cortex is mesodermal in origin. Adrenal medulla is derived from ectoderm, gonads is derived from mesoderm and thyroid and parathyroidis derived ectoderm.
Q5. Which phylum has balance organs?
Answer : Option A
Explaination / Solution:
Sensory organs like antennae, eyes(compound and simple), statocysts or balance organs are present in phylum Arthropoda.
Q6. Wall of uterus has ------- layers of tissues.
Answer : Option C
Explaination / Solution:
The wall of uterus has three layers of tissues. The outer most layer is called perimetrium followed by myometrium and innermost glandular tissue is endometrium.
Q7. Which of the following metabolites are incorrect pairs?
Answer : Option D
Explaination / Solution:
Ricin and abrin are toxins.
Q8. A polygenic trait is controlled by 3 genes A, B and C. In a cross AaBbCc × AaBbCc, the phenotypic ratio of the offspring was observed as 1 : 6 : x : 20 : x : 6 : 1. What is the possible value of x?
Answer : Option B
Explaination / Solution:
Polygenic trait controlled by three genes will form 8 types of gametes. Combination of 8 types of gametes of male and female each result into 64 types of zygote in different ratio. So, possible value of x is 15 (1:6:15:20:15:6:1).
Q9. A nitrogen fixing microbe associated with Azolla in rice fields is
Answer : Option A
Explaination / Solution:
A number of microbes are present in rice field, Azolla and Anabaena are two common bacteria found in rice field that fix the atmospheric nitrogen.
Q10. In the systemic circulation, blood vessel that carries blood from the intestine to liver is named :
Answer : Option C
Explaination / Solution:
The hepatic portal vein carries blood from intestine to the liver before it is delivered to the systemic circulation.
