Cell Structure

• Eukaryotic cells are cells which contain a nucleus.
• Prokaryotic cells are cells which do not contain a nucleus. An example of a prokaryotic cell is bacteria.
• A cell membrane controls the movement of substances in and out of the cell.
• A nucleus controls cellular activities. It contains DNA and genetic information in the form of chromosomes.
• Mitochondria is the site of aerobic respiration where energy is released.
• Ribosomes are the site of protein synthesis.
• Cytoplasm is a jelly-like substance where chemical reactions occur.
• A vacuole is found in plant cells and is permanent. It contains cell sap and provides structure and support to the cell.
• Chloroplasts contain chlorophyll to absorb light energy for photosynthesis.
• Cell walls are made of cellulose and strengthen the cell.
• Label the Diagram

  A) Nucleus

  B) Cell Membrane

  C) Cytoplasm

  D) Mitochondria

  
• Label the Diagram

  A) Nucleus

  B) Vacuole

  C) Chloroplast

  D) Mitochondria

  E) Cell Wall

  F) Cell Membrane

  G) Cytoplasm

  
• Four examples of specialised cells are palisade cells, sperm cells, red blood cells and root hair cells
• Label the Diagram

  A) DNA Strand

  B) Cell Membrane

  C) Flagellum

  D) Plasmid

  E) Cytoplasm

  F) Cell Wall

  G) Ribosomes

  
• Name the sub-cellular structures present in an animal cell. Nucleus, cell membrane, cytoplasm, ribosomes and mitochondria.
• Name the sub-cellular structures present in a plant cell. Nucleus, cell membrane, cell wall, cytoplasm, ribosomes, mitochondria, vacuole and chloroplasts.
• Name the sub-cellular structures present in a bacterial cell. Ribosomes, plasmids, flagellum, cell membrane, cytoplasm, cell wall and circular strand of DNA.
• Binary fission is the name for the process which in bacteria reproduce.
• DNA and plasmid replicate. DNA copies, gets bigger and spreads out. The cell begins to divide and develop new cell walls. The cell divides and two daughter cells are produced.
• Binary fission produces identical DNA but varying plasmids.
• Cells are the basic unit of all forms of life
• Differences in cells are controlled by genes in the nucleus.
• For an organism to grow, cells must divide by mitosis producing two new identical cells.
• If cells are isolated at an early stage of growth before they have become too specialised, they can retain their ability to grow into a range of different types of cells. This phenomenon has led to the development of stem cell technology. This is a new branch of medicine that allows doctors to repair damaged organs by growing new tissue from stem cells.
• Plant and animal cells (eukaryotic cells) have a cell membrane, cytoplasm and genetic material enclosed in a nucleus.
• Bacterial cells (prokaryotic cells) are much smaller in comparison. They have cytoplasm and a cell membrane surrounded by a cell wall. The genetic material is not enclosed in a nucleus. It is a single DNA loop and there may be one or more small rings of DNA called plasmids.
• Most animal cells have the following parts:

  • a nucleus

  • cytoplasm

  • a cell membrane

  • mitochondria

  • ribosomes

  In addition to the parts found in animal cells, plant cells often have:

  • chloroplasts

  • a permanent vacuole filled with cell sap.
• Plant and algal cells also have a cell wall made of cellulose, which strengthens the cell.