Chapter 4

Eukaryotic Cell

• Cilia – filamentous structures on the surface of the cell. They are short and numerous.

• Flagella – filamentous structures. They are long and few.

• Help the cell to move• Cell walls• Plant cells have cellulose cell wall.• Fungi have chitin cell wall.

• Animal cells have no cell walls.• They have glycocalyx (sugar coat) made

up of carbohydrates. Protects the cell.• Plasma membrane – proteins, lipids and

carbohydrates. Encloses the cytoplasm.• Cytoplasm – cytoskeleton• Microfilaments, microtubules, intermediate

filaments.

• Cytoskeleton is involved in cytoplasmic streaming.

• Cytoplasm circulates within the cell such that the nutrients are distributed throughout the cell.

DNA – packaged into nucleosomes

Segments of DNA are wrapped aroundHistone proteins.

lipids proteins

Ribosomes

• Free in the cytoplasm• Show up as dots in a micrograph.• Made up of two subunits.• Each subunit is made up of proteins and

ribosomal RNA.• Eukaryotic cell has 80s ribosomes.• Larger and denser than prokarytoic

ribosomes.

Proteins and lipids made in the ERTransported to golgiModified - lipid added to protein – lipoproteinTransported to other parts of the cell

Power house – cellular respiration

DNA

70S ribosomes

Photosynthesis DNA70S ribosomes

Chlorophyll

• Lysosomes• Membrane bound vesicles• Membrane bags filled with digestive

enzymes.• White blood cells have a large number of

lysosomes.• These cells specialize in destroying

microbes.

• Vacuole – cavity surrounded by a membrane.

• Plant cells have large water vacuoles.• Leaves and stems more rigid.

• Centrioles – cylindrical• Made up of proteins• Flagella and cilia grow out of centriole