cell biology(topic 1)

• Eukaryotic cells


  They have genetic material that forms
• Specialised cells


  • Cells in animals and plants differentiate to form different types of cells
  • Most animal cells differentiate at an early stage of development
  • A plant's cells differentiate throughout
• Specialised cell


  • Adapted to carry out specific functions in the body
  • Contain organelles suited to their function
• Diffusion


  The spreading out movement of particles from an area of higher concentration to an area of lower concentration
• Factors affecting diffusion

  • Concentration
  • Temperature
  • Membrane
• Diffusion


  1. Particles move down their concentration gradient

  2. No energy required
• Osmosis


  The movement of water molecules from an area of lower solute concentration to an area of higher solute concentration through a partially permeable membrane
• Active transport


  The movement of particles against their concentration gradient, requiring energy
• Diffusion in humans


  • Oxygen diffuses from the air in the alveoli into the blood in the capillaries
  • Urea diffuses from the blood in the kidney tubules into the urine
• Diffusion in fish


  • Oxygen from the water passing over the gills diffuses into the blood
  • Carbon dioxide from the blood diffuses out through the gills into the water
• Diffusion in plants


  • Carbon dioxide used for photosynthesis diffuses into the leaves through the stomata
  • Oxygen produced during photosynthesis diffuses out of the leaves through the stomata
• Active transport in humans

  • Nutrients in the small intestine are actively transported into the blood
  • Ions are actively transported from the soil into the root hair cells
• Active transport in plants

  • Minerals are actively transported from the soil into the root hair cells
  • Sugars are actively transported from the leaves to other parts of the plant
• Specialised cells have adaptations that enable them to carry out their specific functions
• Diffusion is a passive process that does not require energy
• Osmosis is the movement of water molecules from an area of lower solute concentration to an area of higher solute concentration through a partially permeable membrane
• Active transport is the movement of particles against their concentration gradient, requiring energy
• rough ER has ribosomes attached to it, smooth ER does not have any ribosomes on its surface
• ribosomes are the site of protein synthesis
• The nucleus contains genetic material (DNA) which controls all activities within the cell.
• The cytoplasm is where most chemical reactions take place.
• the rough endoplasmic reticulum (RER) is involved in the production of proteins
• Mitochondria produce ATP by aerobic respiration.
• Lysosomes contain digestive enzymes used to break down waste materials inside cells.
• Chloroplasts contain chlorophyll and carry out photosynthesis.
• Vacuoles store substances such as food or waste products.
• Vacuoles store water, nutrients, pigments, and wastes.
• Plant cells have a rigid cell wall made from cellulose that provides support and protection.
• Cilia are hair-like structures that move fluids over surfaces.
• Cell membranes are made up of phospholipids and control what enters and exits the cell.
• Cell membranes are selectively permeable and allow certain molecules to pass through while preventing others.
• The nucleus is surrounded by a double membrane called the nuclear envelope.
• what type of cells are animal and plant cells?

  eukaryotic cells
• what type of cells are bacteria cells?

  prokaryotic cells
• what are cells?


  the smallest units of life that can replicate independently
• true or false: animals and plant cells are multi cellular

  true
• what do both animal and plant cells contain?

  cell membrane nucleus cytoplasm mitochondria ribosomes
• what is the function of the cell membrane?


  controls which substances can pass in and out of the cell
• What is the function of the nucleus?

  contains the genetic material/DNA of the cell and effectively controls the activities of the cell.
• what is the function of cytoplasm?

  gel-like substance where chemical reactions take place