lecture.04 - EUKARYOTES basic features of all cells plasma...

EUKARYOTES
- basic features of all cells:
- plasma membrane
- a selective barrier that allows sufficient passage of oxygen,
nutrients, and waste to service the volume of the cell
- general structure is a double layer of phospholipids
- semifluid substance called the cytosol
- chromosomes (carry genes)
- ribosomes (make proteins)
- prokaryotic cells lack a nucleus and membrane-bound organelles
- eukaryotic cells are generally much larger than prokaryotic cells
- eukaryotic cells have membrane-bound organelles
- eukaryotic cells have DNA in a nucleus that is bounded by a
membranous nuclear envelope

Eukaryotes: Panaramic View
- plant and animal
cells have most of
the same organelles

Eukaryotes: Nucleus
- the nucleus contains most of the cell’s genes and is usually the
most conspicuous organelle
- the nuclear envelope encloses the nucleus, separating it from the
cytoplasm ; made of two contiguous membranes
- interior primarily of chromatin , DNA and associated proteins
- the nucleous manufactures tRNA , which leaves the nucleus to
be transcribed into proteins
- the nucleolus manufactures rRNA is manufactured, which leaves the
nucleus to combine with ribosomes