Lecture #5 Chapter #3 Flashcards
What are the three parts of the cell?
The cytoplasmic membrane, the cytoplasm, and the nucleus
Why are the four characteristics of the cytoplasmic membrane?
Extremely thin, flexible, increases surface area of the cell, and maintains the integrity of the cell
How does the term fluid mosaic relate to the cytoplasmic membrane?
Mosaic because it is composed of many different parts such as proteins and lipids and fluid because it’s movable, flexible, and constantly moving
What does selectively permeable mean?
It means the cytoplasmic membrane controls the entrance and exit is substances into the cell
What is signal transduction?
A function of the cytoplasm big membranes that allows the cell to receive and respond to incoming messages
How can the cytoplasmic membrane be thought of?
As the gate or the border of the cell
What are the structures of the cytoplasmic membrane?
Lipids, proteins, and a few carbohydrates
How do lipids work in the cytoplasmic membrane?
Because they are made of phospholipids with water soluble heads (phosphate groups) and water insoluble tails (fatty acids), only molecules soluble in lipids can pass through while the membrane is impermeable to water soluble molecules
What can pass through the cytoplasmic membrane?
Non-polar substances (I.e. O2, CO2, and steroids)
What is cholesterol?
A special type of lipid
What is cholesterols function in the cell membrane/cytoplasmic membrane?
It makes it more impermeable to water soluble substances and help stabilize the membrane
When the fatty acid tails get hot and starts to spin it prevents this, and prevents crystallization when the cell gets cold
What are the two categories for proteins in the cytoplasmic membrane?
Integral proteins and peripheral proteins
What is the purpose of an integral protein?
Forms pores, channels, and carriers in the cell membrane, and transduce signals
What is a channel protein?
A type of integral protein
What do receptor proteins do?
Respond to extracellular signals
What do enzymes do?
Catalyze chemical reactions
What are the four types of peripheral proteins?
Receptor proteins, enzymes, cell surface proteins, and cellular adhesion molecules
What do cells surface proteins?
Establish self/mark the cell as what it is
Function in immune system in blood tissue typing
What do cellular adhesion molecules do?
Enables cells to stick together
What are the 8 structures of the cytoplasm?
Cytosol, ribosomes, endoplasmic reticulum ER, vesicles, Golgi apparatus, mitochondria, lysosome, and peroxisome
What is the fluid portion of the cytoplasm called?
Cytosol
What does organelle mean?
Baby organ
What are inclusions?
Temporarily stored nutrients or pigments within the cell
What is the cytoskeleton?
A framework of supportive protein rods and tubules
What are ribosomes made of?
1/3 protein and 2/3 RNA
What is the function of ribosomes?
Structural support in enzymatic activity to link amino acids to synthesize proteins
What is unique about ribosomes?
They are not contained or composed of membranes like other organelles
Where are ribosomes located?
Scattered throughout the cytoplasm or bound in the endoplasmic reticulum
What are the two types of endoplasmic reticulum?
Smooth and rough
What is the function of rough ER?
Because it is studded with ribosomes, proteins are synthesized here and move through transport where they are folded in 3-D shapes and sent to the Golgi for further processing
What is the function of smooth ER?
Because it lacks ribosomes, it contains enzymes that are important in synthesizing lipids.
Lipids synthesized here are added to proteins coming from the rough ER
What is ER composed of?
Flattened sacs, cylinders, and fluid-filled bubble-like sacs called vesicles
What are the two functions of ER?
Tubular transport and participate in the synthesis of proteins and lipids
Where is ER located within the cell?
Interact with the nuclear envelope and the cell membrane, and they wind from the nucleus to the cell wall like a rail system from a large city to the the suburbs
Where does protein go after it is synthesized?
To the Golgi apparatus
How do you tell what a cells role is?
By looking at what the cell is composed of
Where is an abundance of smooth ER found and why?
It is seen in steroid producing cells such as the liver for breaking down alcohol and drugs
What is a vesicle?
A transport sack
What are vesicles made of?
Membranous sacs
What is the function of vesicles?
Do you transport substances within a cell or between cells
What are the two types of vesicles?
Large and small
Where are large vesicles found?
In the cell membrane, it is when the cell membrane folds and pinches off inward to take in outside material
Where are small vesicles found?
They showed all material from the rough ER to the Golgi apparatus (So they would be found between the two)
What is the Golgi apparatus made of?
5 to 8 flattened membranous sacs called cisternae
What is the role of the Golgi apparatus?
Refines, packages, and transports proteins synthesized on the rough ER
Where is the Golgi apparatus located?
Cells will have several found throughout
What are the five steps in the Golgi apparatus process?
- Proteins (glycoproteins) arrive at the Golgi enclosed in vesicles
- These vesicles fused to the membrane of the Golgi
-  Clayco proteins pass through the Golgi stacks
4. Golgi tags in sorts the molecules so they can be delivered to appropriate places or marked for export - They reach the outer most layer and are packaged in bits of Golgi membrane and bud off inform transport vesicles
What is the Endomembrane transport system?
A group of membranes and organelles that work together to modify, package, and transport lipids and proteins
What are mitochondria made of?
Elongated fluid filled sacs with an outer and inner membrane and a matrix-fluid
What is significant about the inner membrane of the mitochondria?
It folds inward and increases surface area
What is the function of the mitochondria?
Captures and transfers energy from cellular respiration into chemical bonds of ATP that power cellular activities
It also contains its own DNA which make a few types of protein in specialized are in a
Where are the mitochondria located?
Throughout the cytoplasm
What is the lysosome made of?
Small membranes sacs containing enzymes
What is the function of the lysosome?
Autophagy, It is a garbage disposal where sells dispose of their own trash
Where is the lysosome located?
In the cytoplasm, formed from vesicles that originate from the Golgi
What is a disease caused by lysosome dysfunction?
Pompe disease, Which is when the body can’t make a protein that breaks down glycogen
What is peroxisome made of?
Small membrane sacs similar to lysosomes but they contain peroxidase enzymes
What ate the five functions of the peroxisome?
- They use peroxidase enzymes to catalyze metabolic reactions to release hydrogen peroxide
- Synthesize bile acids for fat digestion
- Break down lipids with long fatty acid chains
- Degrade rare bio chemicals
- Detoxify alcohol
What is a disease that results of peroxisome dysfunction?
Leukodystrophy/LAD 
What are the five things that make up the nucleus?
Chromatin, nuclear envelope, nuclear pores, nuclear plasm, and the nucleolus
What is chromatin?
Long molecules of DNA wound around proteins
What is the nuclear envelope?
A inner and outer lipid bilayer membrane
What are nuclear pores?
Channels that allow substances to move between the nucleus in the cytoplasm
What is the nuclear plasm?
The fluid of the nucleus
What is the nucleolus?
A small dense body composed largely of RNA in protein
What is the function of the nucleus?
Stores DNA molecules for the information for synthesis of proteins
What is the location of the nucleus?
Center of the cell
What is the nucleolus?
A small dense body composed of RNA and protein
What happens in the nucleolus?
Ribosome production, once produce they migrate out the nuclear pores to the cytoplasm
What is chromatin?
Consists of 46 chromosomes. Each contains DNA wound round associated proteins-histones
When is chromatin found the tightest?
At the beginning of cell division
What is fundamental biology?
DNA ➡️ mRNA ➡️ protein
What is transcription?
DNA ➡️ mRNA it is all in the language of nucleotides
What is translation?
mRNA ➡️ proteins, information is being translated
What charge does DNA have?
A very negative charge
