{% extends 'base.html' %} {% block title %}annotation{%endblock%} {% block title_num %}
Organelles are small structures that exist within cells . Examples of organelles include mitochondria and chloroplasts , which carry out indispensable functions : mitochondria produce energy to power the cell , while chloroplasts enable green plants to utilize the energy in sunlight to make sugars . All living things are made of cells ; the cell itself is the smallest fundamental unit of structure and function in living organisms . -LRB- This requirement is why viruses are not considered living : they are not made of cells . To make new viruses , they have to invade and hijack the reproductive mechanism of a living cell ; only then can they obtain the materials they need to reproduce . -RRB-
Please check all the words that can be used instead of the target word in the same context. Note that the morphology of the target (third person singular, past tense etc.) is considered to be applied to the candidate automatically in the process of paraphrasing.