Explanation:
The cell nucleus is a membrane-bound structure that contains a cell's hereditary information and controls its growth and reproduction. The main function of the cell nucleus is to control gene expression and mnedite the replication of DNA during the cell cycle.
The answer is carbohydrate
I think the answer is the last one; Flame bulb; flat worm.
A flame bulb or a flame cell is a specialized excretory cell found in the simplest fresh water invertebrates, including flatworms, rotifers and nemerteans; these are the simplest animals to have a dedicated excretory system. Bundles of flame cells are called Protonephridia.
Answer:
Firstly, they are all biogeochemical cycles. They cycle substances through the different systems. So this means that these substances like elements, compounds, and the like go through the hydrosphere, atmosphere, geosphere, and biosphere. It involves both the living and non-living things on Earth, all playing a role in transforming substances into something that can be used, only to be recycled again to provide for the other in a cyclic manner.
For example the oxygen cycle involves how oxygen is produced and used over and over. As we exhale Carbon Dioxide, it gets absorbed by plants which use it, along with water and light, to produce their own food in a process called photosynthesis. A by-product of this process is oxygen which we take in and use and we exhale Carbon dioxide again.