cells pt 2

Boardworks AS Biology Cell Structure Mitochondria The mitochondrion is an energy-generating organelle. It is surrounded by two membranes. The inner layer folds inwards to form the cristae. The cristae project into a liquid called the matrix. outer membrane cristae matrix Teacher notes The folds in the inner membrane (the cristae) provide a large surface area for ATP synthesis. The inner membrane is studded with stalked particles on which the enzyme ATPase (which catalyzes the creation of ATP) is located. inner membrane The inner membrane is coated in enzymes, which catalyze the reactions of aerobic respiration to produce ATP.

Boardworks AS Biology Cell Structure Which organelle?

Boardworks AS Biology Cell Structure Plant cells Plant cells share all the common features of animal cells, but also contain some additional organelles. Plants gain all their energy from sunlight; cells in their leaves contain many chloroplasts to convert this into a useful form. chloroplast vacuole Every plant cell is surrounded by a cell wall, and contains one or more permanent vacuoles. cell wall

Boardworks AS Biology Cell Structure Chloroplasts Chloroplasts use carbon dioxide, water and light energy to build sugars. They are present in all green plants. The chloroplast is surrounded by a double membrane. It is filled with a liquid called the stroma, and contains stacks of thylakoid membranes called grana. grana stroma Teacher notes Chloroplasts use the light energy absorbed by chlorophyll to build sugars. These are converted into complex carbohydrates to store energy for all the plant’s needs. thylakoid membrane The thylakoid membranes are the site of photosynthesis.

Eukaryotic organelles Boardworks AS Biology Cell Structure Eukaryotic organelles

Question Liver cells are packed with rough endoplasmic reticulum and mitochondrea. Why?

Answer Liver cells synthesise many proteins, including enzymes and plasma proteins.

Questions for homework Create a table to compare the presence of organelles in a lymphocyte and in a pallisade mesophyll cell. Name a type of plant cell in which you would be unlikely to find chloroplasts.