Medal i believe because i looked it up
Answer:
B. In the real world, random and unpredictable events occur, so the Lotka-Volterra parameters vary over time
Explanation:
Lotka-Volterra equations are mathematical models that explain biological prey-predator interactions among two species, considering the following assumptions,
-
The ecosystem is isolated and closed. There is no migration.
- The whole individuals are reproductively equivalent.
- In the absence of the predator, prey shows an exponential growth rate. The prey is in the ideal environment.
- In the absence of the prey, the predator population decreases exponentially. The predator environment is also ideal, but it is limited by the prey density.
- The predation rate is proportional to the encounters rate, which also depends on density.
- The predators affect the prey populations, making it decrease proportionally to the number of prey and predators present.
- The prey population also influence the predator population, proportionally to the number of encounters between the two species.
In these equations, the variable D is the number of predators, and P the number of preys.
The parameters are always constant:
- a1: predator hunting success.
- r2: predator growth rate.
- a2: the success of the predator in hunting and feeding.
In nature, there are many factors affecting interactions. Dense-dependent factors and dense-independent factors. Also in reality there are stochastic factors. <em>Stochasticity refers to the variability in the system involving those factors that are affecting or influencing the population growth. Stochasticity might be related to good years and bad years for population growth.</em>
In a real situation, the compliance of the whole assumptions does not occur. The previously mentioned constants might vary, changing continuously the interaction among the predator and the prey. These parameters change in different degrees, resulting in different circumstances for both species.
Answer:
4, 3 5, 1, 2.
Explanation:
The events of muscle contraction begins from the presynaptic neuron, which cause the influx of Ca+, and the release of acetycholine neurotransmitter into the synaptic cleft.
The Ach, binds with the receptors in the sarcolemma, leading to opening of Ligand gated Na+ channels. Therefore Na+diffuses in, causing depolarization, and propagation of action potential along the sarcolemma spreading to the T-tubules.
This is followed by opening of Calcium channels leading exist of Ca+ from the sarcoplasmic reticulum.
The Calcium binds with the troponin, and Tropomysoin exposed the myosin binding sites on the actin filament.Thus cross-bridge is formed by the myosin head with thin filaments which shortened the sarcomere, leading to contraction of muscle fibres.
Answer: Components of cell junctions
Explanation:
<u>Fibroblasts are cells located in the dermis,</u> responsible for the formation and remodeling of tissue. They synthesize fibers and maintains the extracellular matrix of the tissue of animals. So, t<u>he extracellular matrix is a structurally complex entity that surrounds and supports the cells found in tissues</u>.
A cell junction a structure that exists within the tissues of animals and they consist of protein complexes that provide contact between cells or between a cell and the extracellular matrix. So if the cells do not appear flattened and do not attach to the extracellular matrix, then there is a problem with the components of cell junctions, which are mostly proteins as it was said before. And since proteins are coded by genetic information stored in DNA, then if there is a mutation in any of those genes, the fibroblast will fail to attach because the protein of the cell junction will be abnormal.