Cell Organelles Notes Organelle: an organ in a cell Cell membrane: is a thin, flexible barrier surrounding the cell Cytoplasm: the material inside the cell membrane but not including the nucleus is called the cytoplasm Mitochondria: release energy from stored food molecules (Makes energy in the form of ATP.) Nucleus: controls most cell activities & contains DNA Nuclear envelope: the nucleus is surrounded by a double membrane layer called the nuclear envelope. It allows material to move into and out of the nucleus. Chromatin : consists of DNA bound to protein. Chromatin condenses to form chromosomes. Chromosomes are structures containing the genetic information. Nucleolus is located inside the nucleus. It produces ribosomes. Cytoskeleton: helps support the cell. It helps the cell maintain its shape. It is also involved in many forms of cell movement. The cytoskeleton is made of microtubules and microfilaments. Centriole: Creates microtubules for the cytoskeleton. Centrioles are only found in animal cells, not plants. Ribosomes: synthesizes (makes) proteins Endoplasmic Reticulum: is an internal transport system that moves substances through the cell; The rough ER contains ribosomes Golgi complex (golgi body/golgi apparatus): packages & ships out substances to other cells Lysosomes : small sacs filled with enzymes. They break down large molecules into smaller particles. Vacuoles: sac-like structures that store food, water, salt, protein and waste