churn in American English. churnverb [ I/T ] [ I ] The water was churning and the boat was rocking. [ M ] The fish churned up the water when we threw them some food. [ T ] fig. Seeing the car ahead flip over churned his stomach.
The nucleus controls everything that happens in the cell. This means that it controls the chemical reactions that take place in both and animal and plant cells. Some organelles in the cell have their own job like mitochondria control the respiratory (for example).
Controls what substances can get into and out of the cell. Plant and animal cells. Cytoplasm. Jelly-like substance, where chemical reactions happen. In plant cells there's a thin lining, whereas in animal cells most of the cell is cytoplasm.