HW 3+4
Golgi apparatus
- consists of stacks of flattened membrane-bound sacs(cisternae) - bounded by double membrane -Noncellulose polysaccharides that form part of the cell wall of plants are synthesized in the
Lysosomes
-An organelle containing digestive enzymes -Lysosomes contain proteins made in the rough ER. However, these proteins have to be modified, sorted and packaged into vesicles that bud off the Golgi apparatus to become lysosomes.
2 ways that lysosomes can be activated
-Fusing with a food vesicle produced by phagocytosis -Fusing with an old organelle
Steps of protein transport through the endomembrane system
1.transport vesicles--from RER 2.proteins are modified--in Golgi 3.proteins are packaged into secretory vesicles 4. proteins are released
Functions of the smooth endoplasmic reticulum
1] Synthesis of Phospholipids and Cholesterol (Liver) 2] Synthesis of Steroid Hormones (Adrenal Gland, Ovary and Testis); Vitamin D (Epidermis of Skin) 3] Detoxification of Drugs (Liver) 4] Storage of Ca+2 in Most Cells and Skeletal Muscle in Particular 5] Glycogenolysis (Liver) 6] Assembly of membrane lipids -The breakdown of glycogen into glucose
The digestive enzymes in the lysosomes are optimally active at
Acid pH
peptidoglycan
Carbohydrate matrix cross-linked by short polypeptide units
Different functions between SER and RER
Cells that carry out extensive lipid synthesis have more smooth ER. Cells that synthesize many proteins have greater amounts of rough ER.
Lysosomes
Digestion of substances taken into the cell, break down of macromolecules in the cell, and autophagy
Organelle
Eukaryotic cells achieve compartmentalization through an extensive endomembrane system that weaves through the interior of the cell and by numerous membrane-bound organelles that form compartments where biochemical processes can occur independently.
RER
Functions that include glycoprotein production and protein sorting and protein synthesis
Lysosomes are formed from vesicles
Golgi Apparatus
endomembrane system include
Golgi apparatus, lysosomes, vacuoles, the endoplasmic reticulum,various types of microbodies
Cytoplasm
Main site of protein synthesis where ribosomes are found
Lysosomes contain enzymes that can degrade
Nucleic acids Carbohydrates Proteins Lipids
Intensive ribosomal rna sysnesis takes place in
Nucleolus
Ribosomal assembly areas in the nucleus are the
Nucleolus
Pili and nucloid
Only found in Prokaryotes
In the cyanobacterium, Prochloron, the bacterial pigments associated with photosynthesis are located in which of the following structures?
Plasma membrane
Which of the following are synthesized in the nucleolus?
Ribosomal RNA
Nucleus
The repository of the genetic information that enables the synthesis of nearly all proteins in a living eukaryotic cell
Two biggests compartments inside eukaryotic cells
The space inside ER: cisternal space(Lumen)+ cytosol
Rough endoplasmic reticulum plays a role in sorting proteins that are destined for
Vacuoles Plasma membrane Lysosomes
Prokaryotes consists of two categories of organisms
archaea and bacteria
What structure is present in nearly all prokaryotes to support and protect the plasma membrane?
cell wall
The most common alteration made in the Golgi body
is addition or modification of short suagr chain-- forming glycoproteins and glycolipids
The surface of the nucleus is bounded by two phospholipid bilayer membranes, collectively called the
nuclear envelope
Prokaryotes differ from eukaryotes because they lack a membrane-enclosed
nucleus
What do prokaryotes lack?
nucleus
the largest organelle present in eukaryotic cells
nucleus
A strong cell composed of
peptidoglycan
Cyanobacteria have folds in their
plasma membrane
What structure functions in polypeptide synthesis?
ribosome
Structures called ______ are found in both prokaryotic and eukaryotic cells and are the sites of polypeptide synthesis.
ribosomes
Golgi apparatus
stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum
