Answer:
3rd generation = 2 Hybrid DNA molecules + 6 Light DNA
In Percentage 2÷8 × 100 = 25%
25% of the DNA are hybrid
Explanation:
Semi conservative model proposed by Watson and Crick states that one strand of the DNA comes from parent DNA which act as a template for the other newly formed strand.
First generation:
If cells containing 15 N DNA are transferred to a medium with only 14 N then in initial first generation two parent strands becomes separated and act as template for newly synthesized strands. this means that in first generation both DNA molecules are hybrid, one strand of 15 N DNA and other strand of 14 N DNA
Ist generation = 2 Hybrid DNA molecules
Second generation:
In Second generation these two hybrid molecules become unzip. Two strands are 15N and two strands are 14N. All these 4 strands act as template and 4 new strands are synthesized. The molecules of Hybrid DNA is still 2 with 2 molecules of Light DNA.
2nd generation = 2 Hybrid DNA molecules + 2 Light DNA
Third generation:
In Third generation these two hybrid molecules and two light DNA molecules become unzip. Two strands are of 15N and six strands are of 14N. All these 8 strands act as template and 8 new strands are synthesized. The molecules of Hybrid DNA is still 2 with 6 molecules of Light DNA.
3rd generation = 2 Hybrid DNA molecules + 6 Light DNA
In Percentage 2÷8 × 100 = 25%
25% of the DNA are hybrid
Scientists use similarities between organisms to connect them. The similarities and contrasts between fossils discovered in sedimentary rock and living species can be compared.
Milk is converted to yogurt under certain conditions when the microorganisms in the milk produce acid. Which of these processes would you expect to be key in the production of yogurt?
a. Photosynthesis
b. Lactic acid fermentation
c. Krebs cycle
d. Alcoholic fermentation
Answer:
b. Lactic acid fermentation
Explanation:
Lactic acid fermentation occurs when pyruvate formed by glycolysis is reduced into lactate under the anaerobic conditions. The NADH serves as an electron donor for the reduction of pyruvate into lactic acid. Lactic acid bacteria are the anaerobic bacteria that ferment the milk sugar lactose into lactic acid. This converts the milk into yogurt. <em>Lactobacillus, Streptococcus salivarius</em>, etc. are mostly responsible for the conversion of milk into yogurt.
