The fossil records of primitive plants show a variety of seed dispersal mechanisms that has been adopted by plants at various stages and how they have evolved. The most primitive of this seed dispersal mechanism is the Anemochory
Anemochory is the dispersal of seed through the wind. The seeds have wing like structures and are lightweight to be able to fly away with the wind. They are dull colored and are pale that will prevent the seed from being visible.
Hydrochory is the next order of evolution of the seed dispersal mechanism which became majorly adopted by plants that tend to grow near water sources and those whose seeds are too heavy to fly in the air. One of the best examples is the coconut that falls off on the sea water in the coastal areas and floats to other lands and sprouts to a new plant.
Barochory is the dispersal of the seed through gravity. This is the mechanism where the fruit falls off to the ground due to gravity and grows into a new plant.
Endozochory is the dispersal of the seed through animals. In this case the seed is usually covered with a fleshy edible part which is consumed by the animals and in this process the seed goes into the digestive system of the animal and is excreted in a different place from where the seed can sprout into a new plant.
Ballochory is the dispersal of the seed due to the forceful ejection of the seed by explosive dehiscence of the seed. This lets the plant to place its seeds in a distant area. One of the best examples is the Hura Crepitans which is also called the dynamite tree, named after its exploding fruits.
Answer:
Option C
Explanation:
Dr. Leland Hartwell used baker’s yeast, <em>Saccharomyces cerevisiae</em>, as a model system, which was a highly suitable model for cell cycle studies. He introduced the concept of Checkpoints where he said cells are arrested if damaged so that the cells repair system can work to correct such damages. Dr. Paul Nurse used a different type of yeast, <em>Schizosaccharomyces pombe</em>, a type of yeast distantly related to the baker's yeast as a model organism.
Answer:b
Explanation:
It will only be found in some cells because when a mutation is formed it will most likely not be able to spread
When that bacteria changes in some way that reduces or eliminates the use of the drug.
Viruses reproduce by incorporating
their DNA into an organism's genome to tap into the
host replication mechanism to reproduce themselves.
Viruses, therefore, cannot copy outside their host. This property of viruses makes them suitable
for the production of transgenic
organisms. This is achieved by replacing
the DNA piece that causes virulence in the virus with the desired gene
that is to be transduced into the host organisms.