Eukaryotic Cells IB Topic 2.3

What is a eukaryotic cell? Algae Fungi Animals (like us!) Plants See figure 2.2 on page25 How does it compare to a prokaryotic cell?

Features of eukaryotic cells 5 – 100 μm (larger than prokaryotic cells) Has a nucleus Organelles Non-cellular structures Specific structure and function Two types of eukaryotic cells: Animal cell Plant cell

Organelles of eukaryotic cells See figures 2.2 and 2.3 Endoplasmic reticulum (ER) Ribosomes Lysosomes (not usually in plant cells) Golgi apparatus Mitochondria Nucleus Chloroplasts (only in plant cells) Vacuoles

Cytoplasm Inside the plasma membrane Which is the outer boundary of the cell It is the region that the organelles occur

Endoplasmic reticulum (ER) Figure 2.5 Network of tubes (or channels) Extends throughout the cell Transportation of materials throughout the cell Two types: Smooth No ribosomes Enzymes Rough Studded with ribosomes Protein synthesis

Ribosomes Protein synthesis Free in cytoplasm or attached to the rough ER Ribosomes of eukaryotic cells are larger than those of prokaryotic cells Eukaryotic ribosomes = 80 s (size) Prokaryotic ribosomes = 70 s (size)

Lysosomes Sac-like Breaks down protein, nucleic acids, lipids and carbohydrates Breaks down damaged organelles & materials Lyse means to break down

Golgi apparatus Collection, packaging, modification, and distribution of materials Receives products from the ER ER  Golgi apparatus  vacuoles

Mitochondria (mitochondrion) Close to the size of a bacterial cell Has its own DNA Has its own ribosomes (70s) Double membrane Powerhouse of the cell Produces chemical energy called ATP Cells that have a lot of energy requirements, like muscle cells, have large numbers of mitochondria

Nucleus Isolated region where the DNA resides Double membrane Called the nuclear membrane or envelope DNA exists in the form of chromosomes Number varies based on the organism Humans have 46 chromosomes Carry out all the information that is necessary for the organism to live

Chloroplasts Only in plant and algae cells Double membrane Has its own DNA and ribosomes (70s) This is where photosynthesis occurs

Turn and talk What are characteristics that chloroplasts and mitochondria have in common with prokaryotic cells?

Vacuoles Form from the Golgi apparatus Occupy a very large space in plant cells Used for storage Food (nutrition) Wastes/toxins (to be expelled later) Water

Exit Slip: Create a Venn diagram comparing prokaryotic and eukaryotic cells