unit 4 - cell biology honors

hooke (1665)

• first to use the term “cell” to describe the structures that make up all living things

• observed cork cells (dead)

leeuwenhoek (1670’s)

• father of modern microbiology

• first to observe living cells

cell theory

1. all organisms are composed of one or more cells

2. cells are the basic units of structure and function for all living things

   1. (each cell must maintain life)

3. cells arise only from other pre-existing cells

prokaryotic cells

• simplest, most ancient/oldest types of cell

• found only in bacteria

• no nucleus & no membrane bound organelles

  • mitochondria, E.R., etc.

eukaryotic cells

• more modern, complex cells

• contains nucleus and “membrane-bound” organelles

• found in plants, animals, fungi, protists

what organelles/structures do every cell have?

• cell membrane (plasma membrane)

• cytosol (cytoplasm)

• ribosomes

• DNA (genetic material)

what organelles/structures are found in both animal/plant cells?

• cell membrane (plasma membrane)

• cytosol (cytoplasm)

• nucleus

• nucleolus

• E.R.

• ribosomes

• golgi apparatus

• mitochondria

• lysosome

• peroxisome

• cytoskeleton (microtubules & microtubules)

• vacuole

what organelles/structures are only found in plant cells?

• cell walls

• plastids

  • chloroplasts

  • chromoplasts

  • leukoplasts

what organelles/structures are only found in animal cells?

• centrioles

cell membrane (plasma membrane)

• outer boundary of the cell; separates the cell from the external environment

• regulates what goes in or out of cell

cytosol (cytoplasm)

clear fluid filling the cell in which organelles are suspended

nucleus

• contains the genetic material; controls the activities of the cell

• surrounded by nuclear membrane

nucleolus

• found within nucleus

• site where ribosomes are made

endoplasmic reticulum

• ‘intracellular highway”

• system of transport tubules within the cell

• smooth = no ribosomes

• rough = with ribosomes

• helps fold + modify proteins

ribosomes

• location where proteins are assembled

• most numerous organelle

• creates polypeptides

golgi apparatus

• packaging and processing organelle

• proteins are modified and prepared for export

mitochondria

• “powerhouse” of the cell

• location where ATP is made by aerobic respiration

lysosome

• contain digestive enzymes, break down foods and worn out cell parts

peroxisome

• small, membrane-bound

• contain toxic peroxides that are safely broken down

cytoskeleton

• microtubules/microfilaments

• provides shape and support for the cell

vacuole

• storage organelles

• stores materials and wastes

centrioles

aid in cell division

cell walls

• found outside cell membrane

• made of cellulose (plants)

• provides support

chloroplasts

• contain chlorophyll

• site of photosynthesis

chromoplasts

contain accessory pigments that aid in photosynthesis

leukoplasts

store starch; white

cell specialization

not all cells found within an organism are similar looking. many cells have a specialized structure that enables them to better carry out their specific function.