<em>Cilia and flagella</em> - threadlike structures that assist in movement.
Cilia and flagella are structures made from microtubules. Besides assisting in movement, depending on the type and the location of the cilia, they may also function as a means of transportation for different molecules and have sensory functions that allow the cell to respond to the changes in its environment.
<em>Endoplasmic Reticulum</em> - tube-like structures that are the site of protein and lipid synthesis.
Endoplasmic Reticulum is an organelle composed of cisternae. It has two parts: one that is rough and focuses on the production of proteins, and one that is smooth and is responsible for the synthesis of lipids.
<em>Mitochondria</em> - the sites of cellular respiration and energy production.
Mitochondria are a fundamental part of the cell, since their main -but not only- function is to produce the energy necessary for all cell processes, from transportation to synthesis of DNA.
<em>Chloroplasts</em> - contain chlorophyll and are the site of photosynthesis.
Chloroplasts are organelles that can be found in plant cells. It transforms sunlight into chemical energy to later use it for the production of sugar for the plant to consume.
<em>Lysosomes</em> - digestion organelles that break down biomolecules into smaller molecules.
Lysosomes are found in animal cells. In their interior, they possess many enzymes that specialize in the degradation of biomolecules. These enzymes work at a very acidic pH, meaning that if the lysosomal membrane were to break, the enzymes would still not be able to destruct the cellular components because of the alkaline nature of the cytosol.
<em>Centrioles</em> - cylindrical tubular organelles that are involved in cell division.
Also formed by microtubules, Centrioles organize the mitotic spindle, a key element for cell division to occur.
(the Centrioles option wasn't given in the question, but it's the organelle that matches to the description that was being left out).
