DNA Replication

The process of replicating DNA requires several enzymes and proteins. By separating the process into parts such as Initiation, Elongation and Termination we make it easier to understand.

Initiation
As we all know DNA is in a form of a double helix, so before replication begins we have to first unwind that double helix. To unwind the DNA we use the enzyme Helikase. As soon as the DNA become unwound they also become single-stranded. When DNA is single stranded they become weak and can break easily. This is when singe stranded binding protiens come in to stabilize the DNA. Lastly we have the enzyme Gyrase that releases the tension from the DNA.

Elongation
Elongation starts when primase puts down a primer on the DNA. This primer acts as a signal that DNA polymerase can latch onto. In the leading end DNA polymerase III moves across the DNA from 5' to 3' and copies the genetic code from the parent strand. Polymerase I also helps by proofreading the daughter strands code and making sure it matches with the parent strand. However int he lagging end, DNA has to be copied discontinuously. Primase has to put down primers multiple times and Polymerase III has to latch onto those primers and copy genetic code only in small segments.

Termination
During the last step, Termination DNA ligase joins the okasaki fragments and completes the lagging end of the daughter DNA strand.

Anabolism - Metabolism - Catabolism

Anabolism - is the set of metabolic pathways that construct molecules from smaller units. These reactions require energy. Usually require energy from ATP.

examples :

Cyclic Cycle

Calvin Cycle

Non Cyclic Cycle

Metabolism: is the set of life-sustaining chemical transformations within the cells of living organisms. These enzyme-catalyzed reactions allow organisms to grow and reproduce, maintain their structures, and respond to their environments.


Catabolism: is the set of metabolic pathways that breaks down molecules into smaller units to release energy.

Examples:

Glycolisis

Kreb Cycle

Rafflesia

The ROM is one of the best museums in Canada and on Oct 31st my biology class and I were given the privilege to attend a tour. During the tour what amazed me the most was a flower called the Rafflesia.

The Rafflesia is the worlds heaviest flower and surprisingly this flower has no stems leaves or true roots. The Rafflesia is also sometimes known as the corpse flower because it gives off the smell of rotting flesh. Other flowers release a descent scent in order to attract insects for pollination. The fact that the Rafflesia has a rotting scent indicates that the insects it targets are flies and other organisms attracted to the smell of rotting.

The rafflesia that was on display at the ROM was unfortunately a life sized replica. Having a real flower in a museum would be unrealistic as it would probably wilt and die.Other than smelling like a corpse the Rafflesia is also known for having no leaves and stems. The red petals on the flower show that it cant photosynthesis. How can a plant survive without phphotosynthesis. The Rafflesia is actually a parasite. It has roots however these roots dont get minerals from the soil, the Rafflesia's roots suck nutrients from other plants. It is with this method that the Rafflesia has no need to photosynthesis. The Rafflesia also has very strict blooming seasons, it will only bloom once a year and wilt in around 3 days. The Rafflesia blooms have to be synchronized or else pollination bettween males and females wont occur.