Cells and organelles

• what are the two types of cells?

  Prokaryotic and Eukaryotic.
• what is an organelle?

  A specialized structure within a cell that performs a specific function.
• What does a plant cell have that an animal cell doesnt have?

  A cell wall

  A permanant vacuole

  Chloroplasts#
• what is a description of the plasma membrane?

  The membrane found on the surgave of animal cells, and inside the cell wall in plant/prokaryotic cells. It is mainly made out of lipids and proteins
• What is the function of the plasma membrane?

  The function of the plasma membrane is to regulate the movement of substances in and out of the cell and to maintain the cell's internal environment. It also has receptor molecules which allow it to respond to chemicals such as hormones.
• what is a description of the cellwall?

  A rigid structure that surrounds plant cells. It is mainly made of the carbohydrate cellulose.
• What is the purpose of the cell wall?

  Protection and support of plant cells.
• what is a description of the nucleus?

  It is a large organelle surrounded by a nuclear envelope whjich contains many pores. The nucleus contains chromatin and often a structure called the nucleolus.
• What is the function of the nucleus?

  The nucleus controls the cell's activity by controlling the transcription of DNA. Dna contains instructions to make proteins. The pores allow substances like RNA to move between the nucleus and cytoplasm.
• What is a description fo the lysosome?

  A round organelle surrounded by a membrane, with no clear internal structure.
• What is the function of the lysosome?

  The lysosome contains digestive enzymes, these are kept seperate from the cytoplasm by the membrane. The enzymes can be used to digst invading cells or to break down worn out components of the cell.
• What is a description of the ribosome?

  A very small organelle that either floats free in the cytoplasm or is attached to the rough endoplastic reticulum. The ribosome is made up of proteins and RNA. It is not surrounded by a membrane.
• What is the function of the ribosome?

  The ribosome is the site of protein synthesis.
• What is a description of the rough endoplastic reticulum (RER)?

  A system of membranes enclosing a fluid-filled space. The surface is covered with ribosomes.
• What is the function of the rough endoplastic reticulum?

  Folds and processes proteins that have been made at the ribosomes.
• What is a description of the smooth endoplastic reticulum?

  Network of membrane-bound tubes and sacs.
• What is the function of the smooth endoplastic reticulum?

  Lipid synthesis and detoxification.
• what is a description of the centriole?

  Small, hollow cylinders, made up of microtubules. It is found in animal cells and some plant cells.
• What is the purpose of centrioles?

  Centrioles are involved in the seperation of chromosomes during cell division.
• What is a description of cilia?

  Small, hair-like structures found on the surface membrane of some animal cells. In cross-sections, they have an outer membrane and a ring of nine pairs of protein microtubules with a single pair in the middle.
• What is the purpose of cillia?

  The microtubules allow the cillia to move, this movement is used by the cell to move substances along the cell surface.
• what is a description of the flagellum?

  Flagella on eukaryotic cells are like cillia but longer. They stick out from the cell surface and are surrounded by the plasma membrane. Inside, they are like cillia too with two microtubules in the centre and nine around the edges.
• What is the function of the flagellum?

  The microtubules contract to make the flagellum move. Flagella are used lke outboard motors to propel cells forwards.