Answer:
DNA ligase
Explanation:
DNA replication is a process whereby a particular DNA makes a copy of or synthesizes itself. It consists of several steps with some important enzymes for successful, error free replication. The various steps are as follows;
- Unwinding of the double helix structure of the DNA and formation of replication fork. The enzyme involved here is the DNA helicase.
- Primer, a short piece of RNA becomes synthesized and binds to the 3' end of one of the 2 strands of the DNA, the leading strand. The enzyme involved is the DNA primase.
- Replication of the <em>leading strand</em> then proceeds with the elongation of the primer through the addition of bases in the 5' to 3' direction leading to the formation of continuous strands.
- The other strand of the DNA, known as the <em>lagging strand </em>starts its own replication by binding with multiple primers at different regions of the strand. Bases are then added to each primer leading to the formation of several, short discontinuous DNA strands known as Okazaki fragments. The enzyme involved in the elongation process is the DNA polymerase.
- Next is the termination of the replication process after the formation of the continuous and discontinuous strands. Exonuclease enzyme removes primers from the synthesized strands. Primers are replaced by appropriate DNA bases and the Okazaki fragments are joined to form a unified DNA strand by an enzyme known as the DNA ligase.
The many, few nucleotides long DNA segments observed by the Biochemist are the Okazaki fragments that should have been joined together by the DNA ligase.
Hence, DNA ligase must have been the component left of the mixture.
I believe it’s B. Dont take my word for it
Crustacea(ns) form a very large group of arthropods.
Answer: The colour of A before the starch test is GREEN while after the starch test is BLUE- BLACK. The equation for photosynthesis is
6CO2 + 6H2O → C6H12O6 + 6O2.
Explanation:
PHOTOSYNTHESIS is the process by which green plants use energy from sunlight to manufacture their own food. It is a building up process since simple inorganic compounds such as carbondioxide and water are built up into large organic compounds such as glucose and OXYGEN is given off as a by product.
Oxygen given out in photosynthesis occurs in the light stage during the process of photolysis of water. This occurs when the chlorophyll traps, absorbs and captures light energy and become energised. The energised chlorophyll supplies energy which is to split molecules of water into hydrogen ion ( H+) and hydroxyl ion ( OH-). The hydroxyl ion is reconverted to water and oxygen is given out as a by product.
To show that chlorophyll is NECESSARY for photosynthesis, a variegated leaf with green and yellow patches is used for an experiment.
The green portion is marked A and the yellow portion marked B. The leaf is tested for starch using the procedure below:
--> place leaf in boiling water for half a minute to kill it.
--> decolorize leaf by placing it in hot alcohol.
--> dip decolorize leaf in hot water to soften it.
--> place leaf on tile and add iodine solution to it.
RESULT: It would be found that only the green parts contain starch as blue+black colouration is observed while yellow area is unaffected by iodine.