2.2

• cells - the basic unit of life, all living things are made up of cells.
• tissues - a group of cells with similar structures and function
• organs - group of tissues that work together to perform a specific function
• organ system - a group of organs that work together to perform a specific function
• three factors that limit our ability to see a cell

  • Type of microscope
  • Power of the lens
  • Quality of the prepared slides
• organelles - specialized structures within a cell
• cell membrane - controls what goes in and out of the cell, a barrier that surrounds the cell
• cell wall - only in plant cells

  • provides structure and support
• cytoplasm -

  • A liquid inside the cell which has grainy-looking bits in it
  • Contains nutrients required by the cell to maintain its life processes
• nuclear membrane -

  • isolates the interior of the nucleus from the cytoplasm
  • It controls what enters and exits the nucleus
• Nucleolus - contains DNA and directs the cell
• vacuoles -

  • Clear liquid-filled spaces in various places within the cytoplasm
  • nutrients, water or other substances are stored by the cell
  • Plant cells have 1 big vacuole
  • Animal cells have many small vacuoles
• mitochondria -

  • The “powerhouse” of the cell where chemical reactions occur (converts the energy in the cell receives into a form it can use)
  • cellular respiration occurs here
• cellular respiration -

  • Cellular respiration is the process where nutrients are converted into energy and where waste products are produced
• chloroplasts -

  • Found in the cells of the green parts of plants
  • They carry out photosynthesis
  • Only found in plant cells
• plant cell

  A) cytoplasm

  B) nucleas

  C) nucleolus

  D) nuclear membrane

  E) mitochondrion

  F) chloroplast

  
• animal cell

  A) vacuole

  B) cytoplasm

  C) nucleolus

  D) nucleas

  E) mitochondrion

  F) lyosome