<u>Answer:</u>
The correct answer is Uracil which is nitrogen base found in RNA.
<u>Explanation:</u>
Uracil is a nitrogenous base which is located within an RNA molecule but not within a DNA molecule.
Uracil, represented by the letters A, G, C and U, is one of the four nucleobases that are found in the nucleic acid of RNA which binds to adenine.
While thymine is present in the DNA and binds to adenine.
Answer:
Watson and Crick proposed the double helical model of DNA.
Explanation:
- This model says that DNA exist as double helix. It has two polynucelotide strands running in opposite direction i.e the strands are anti-parallel.
- Each polynucleotide strand is made up of several nucleotide liknked together by phophodiester bonds.
- The two strands are not coiled upon each other but the double strand is coiled upon itself around a common axis like the spiral stair case. Here base pairs forms the stairs and backbone of two strands form railing. Back bone contains sugar and phosphate.
- The base pairing is specific, adenine always pairs with thymine and guanine always pairs with cytosine. Thus if we see any base pair, it consists of one purine and one pyrimidine.
- The two strands of DNA thus show complementary base pairing.
- The strands are held together because of hydrogen bonding between the bases in opposite strand.
- One full helical turn involves ten base pairs and the base pairs are stacked 3.4 A apart.
- This form is called as B-form of DNA.
Answer:
1: B
2: C
3: D
4: D
5: B
6: C
7: A
Explanation:
Alleles: alternative forms of a gene
Gametes: sex cells that are the product of meiosis
Genes: unit of hereditary, made up of DNA
Traits: specific characteristic of an organism
Answer:
B. After clearcutting, plant uptake stopped and nitrogen accumulated in the soil.
Explanation: Clear cutting leaves the soil bare and allows for direct penetration of sunlight this increases the soil temperature which favors the activity of soil microrganism. This microrganism activity increase the production of ammonium and nitrate hence the increase in soil Nitrogen level. Clearcutting then allows for accumulation of Nitrogen produce due to removal of plant or forest tree that could use up the Nitrogen produced.
Answer: The operations of importance in fish processing are washing, degutting, salting, fermentation, drying, and smoking. These operations contribute to the development of flavor, texture, color, and improved storage characteristics of the products.
Explanation:
