the importance of different types of relationships and interactions between organisms Flashcards
importance of interactions and relationships in the nitrogen cycle
-in nitrogen fixation the nitrogen fixing bacteria in the root nodules of legumes and free living bacteria in the soil use the enzyme nitrogenase to reduce gaseous nitrogen into ammonia. an example of this is the mutualistic bacteria rhizobium which forms a symbiotic relationship with the plant
-the rhizobium provides the plants with nitrogen compounds and the hyphae increase the surface area of the root network to increase the water uptake by osmosis
-in return the plant provides the bacteria with carbohydrates formed through photosynthesis
-in ammonification the saprobiotic microorganisms feed on the dead organisms and faeces to release ammonia ions back into the soil through breaking down organic nitrogen containing compounds
-in nitrification the ammonia ions are oxidised into nitrite ions by nitrifying bacteria and more nitrifying bacteria oxidise the nitrite ions into nitrate ions
-microbes enable nitrogen to be absorbed by plants in the form of nitrates which is integral for plant growth and production of essential compounds like proteins and DNA
importance of interactions and relationships in courtship behaviour
-courtship behaviour initiates successful mating between organisms
-courtship behaviour are ritualised actions such as singing or dancing which allows organisms to identify members of their own species which are of the opposite sex
-courtship behaviour can also indicate sexual maturity and fertility which allows an organism to identify a mate that is capable of breeding
-one outcome of courtship behaviour is the formation of a pair bond which increase the likelihood of reproductive success and the passing on of advantageous alleles
-courtship behaviour will increase the population size and ensures the population is adapted to their environment
importance of interactions and relationships between bacteria and B cells in the humoral response
-in clonal selection, specific B cells bind to antigens on the surface of a pathogen
and are stimulated by the release of cytokines by helper T cells
-this causes the b cells to divide rapidly by mitosis to form clones in clonal expansion
-the B cell differentiates into plasma cells for the primary immune response as they secrete large amounts of monoclonal antibodies into the blood
-some B cells differentiate into B memory cells for the secondary immune response so upon reinfection antibody production is faster and at a higher concentration
-the humoral response has been manipulated into medicine as vaccines involve the injecting of weak or dead pathogens into the body to stimulate the production of memory cells against that specific antigen. this means the pathogen will be quickly destroyed upon reinfection
importance of interactions and relationships in natural selection
-random mutation can produce new alleles of a gene meaning genetic variation occurs in the population
-under certain environmental conditions, some individuals possess an advantageous allele which means they have an increased chance of survival and reproduction
-the advantageous allele is passed on to their offspring meaning the the new allele will increase in frequency in the population
-the interactions between competing species in a population makes the entire population more adapted to the environment so there is greater chance or survival
