-Shows darkened patches (chromatin) when stained.
-Surrounded by nuclear envelope - which is made of 2 membranes with fluid between them. This contains nuclear pores - holes large enough for relatively large molecules to pass through.
-Contains a nucleolus.
- Houses nearly all of cell's genetic material.
-The chromatin consists of DNA and proteins. When cells divide, chromatin condenses into visible chromosomes.
-Nucleolus makes RNA and ribosomes
-Consists of a series of flatterned, membrane-bound sacs called cristernae
-ROUGH ER: studded with ribosomes
-SMOOTH ER: No ribosomes
-ROUGH ER: transports proteins made on attached ribosomes
-SMOOTH ER: Lipid synthesis
-Stack of membrane-bound, flattened discs
-Receives proteins from ER and modifies them - may add sugar molecules to them.
-Packages the modified proteins into vesicles that can be transported
-Have 2 membranes separated by a fluid-filled space.
-Inner membrane folded to form cristae
-Central part of mitochondrion is called the matrix
-Site where ATP is produced during respiration
-Found only in plant cells and the cells of some protoctists
-Have 2 membranes separated by a fluid-filled space
-Inner membrane is continuous, with a network of flattened membrane sacs called thylakoids (a stack of these is called a granum)
-Cholorophyll molecules are present on the thylakoid membranes and in the intergranal membranes
-Site of photosynthesis in plant cells. Light energy is used to drive the reactions of photosynthesis, in which carbohydrate molecules are made from carbon dioxide and water
-Spherical sacs surrounded by single membrane
-Contain digestive enzymes which break down materials e.g. white blood cell lysosomes help break down invading microorganisms
-Some found in cytoplasm and some are bound to ER
-Each ribosome consists of 2 subunits
-No membrane surrounding them
-Site of protein synthesis.
-They act as an assembly line where coded information (mRNA) from nucleus is used to assemble proteins from amino acids
-Small tubes of protein fibres (microtubules).
-There is a pair of them next to the nucleus in animal cells and in the cells of some protoctists
-Take part in cell division. They form fibres (spindle fibres) which move the chromosomes during nuclear division