Answer:
A:Lack of rainfall
Explanation:
In Ecology, certain factors affect the population of species in an ecosystem. These limiting factors can either be density dependent or density independent. Based on the question, density independent limiting factors are those factors that affect population size of species irrespective of their density in an ecosystem.
The effect of density independent factors is not dependent on the size of the population, so it tends to affect process limit all populations in the ecosystem. Density independent factors are usually environmental-related e.g natural disasters, lack of rainfall as mentioned in the options.
Lack of rainfall in a particular ecosystem will affect all population species irrespective of how dense they are. Hence, it is a density independent limiting factor.
The right option is; a. A tree grows tall
A tree grows tall is an example of cell division at work because growth is associated with cell division. Also, cell division in multicellular organisms such as plant involves tissue growth and maintenance. Cell division is a process of reproduction in which a cell divides into two or more cells. In this process, production of new cells involves DNA replication and there are various types of cell division. Prokaryotes (such as bacteria) divide their cell using binary fission, while eukaryotes divide their cell by mitosis or meiosis in some.
The concentration of glucose outside the cell is higher than the concentration of glucose inside the cell, thus there is a concentration gradient. The molecules of glucose move randomly and there is a net movement from outside to the inside, down the concentration gradient.
Answer: Ethylene Gas
Explanation: Ethylene Gas Can be Used to Regulate Fruit Ripening Ethylene is a gas and is known as the “fruit-ripening hormone.”