Chapter 4 CMB Cell Organelles Flashcards
What is nucleolus?
Nucleolus is a dense cluster of RNA and proteins which manufacture ribosomes which is important for protein synthesis
What is site of photosynthesis?
A complex process which uses captured light energy to construct organic compounds (glucose) from water and carbon dioxide
The nuclear membrane has nuclear pores. What are nuclear pores?
Nuclear pores control and act as the passageway for materials entering or exiting the nucleus
What is golgi apparatus?
Stacks of membranous sacs that receive and modify ER products (proteins, lipids, carbohydrates)
What are some organelles found in the animal cell? (11 examples)
- Mitochondrion
- Golgi apparatus
- Nucleolus
- Nucleus
- Microtubules
- Ribosome
- Cell membrane
- Smooth ER
- Rough ER
- Golgi vesicles
- Lysosome
What is the function of ribosomes on the surface of the Rough ER?
Produce proteins that are secreted, inserted into membranes, or transported in vesicles to other organelles
What does the cytoplasm contain?
Cytosol + Organelles
Where are vacuoles found?
Vacuoles are found in mature plant cells where they occupy 90% of the cell’s volume
Where are the secretory vesicles transported to?
The secretory vesicles are then transported to the cell surface for release (exocytosis)
What is Smooth ER?
Smooth ER lacks the ribosomes, they are interconnecting network of tubular membrane elements
What is secretory vesicles?
They are cell secretions which are packaged into secretory vesicles at the golgi apparatus
(Example: hormones, neurotransmitters)
What are lysosomes?
Lysosomes are vesicles containing hydrolytic enzymes and are formed from the golgi apparatus
Where are organelles located?
Organelles are structures located within eukaryotic cells that perform one or more function
What us microfilaments?
They are actin and myosin in muscle cells
What are the types of necrosis? (2 types)
- Unintentional
- Following cell damage and rupture of lysosomes - Intentional
- Part of apoptosis (controlled cell death)
- Necessary for survival of organism
- Example: Prevention of cancer
What is the function of Rough ER? (2 functions)
- Protein synthesis
- Transport proteins
What is golgi apparatus?
Stacks of membranous sacs that receive and modify ER products (proteins, lipids, carbohydrates). They ship them to other organelles or the cell surface.
What are the functions of a vacuole? (3 functions)
- Maintain high internal water pressure
- Aids in the support of the plant
- When water is lost from the vacuole through evaporation, the plant wilts
What does the cytoskeleton consist of? (2 examples)
- Microtubules
- Microfilaments
What is Post translational modification?
Modification of the protein to protect, activate or deactivate it
(Example: Glycosylation)
What is granum?
They are a stack of thylakoids
Are centrioles absent in plant cells?
Yes
What is centrioles?
They are structures found within the centrosome and are important in moving chromosomes during cell division
What is the summary of protein synthesis? (5 processes)
- Transcription
- Translation
- Modification
- Packaging
- Secretion
What is cytokskeleton?
Cytoskeleton is the internal system of fibres extending between nucleus and plasma membrane
What is the function of the golgi apparatus?
The golgi apparatus modifies, packages and distributes proteins
What are the functions of lysosomes? (3 functions)
- Digestion chamber for destroying harmful bacteria and foreign bodies
- Site for disposing worn-out organelles
- Causes necrosis (death of cells)
What is Transcription?
Coding of genes in DNA into messenger RNA (mRNA)
(DNA to mRNA)
What is ribosome?
A minute round particle composed of RNA and protein (found in cytoplasm)
What is cytosol?
A liquid or “soup” within which all the other organelles reside
What is stroma?
A semi-fluid interior
What is chloroplast?
Chloroplast are only found in plant cells and its a site of photosynthesis
What are the functions of cytoskeleton? (3 functions)
- Maintains cell shape, strengthen the plasma membrane and internal organisation
- Internal movement of cell organelles
- Muscle fiber contraction
What is the nucleus surrounded by?
The nucleus is surrounded by nuclear envelope/membrane
What is Translation?
Coding of mRNA into proteins (mRNA to proteins)
What is role of centrioles in cell division?
The role of centrioles in cell division is a mystery
What are the structures of chloroplast? (4 main structures)
- Double membrane
- Thylakoids
- Granum
- Stroma
What is centrosome?
It contains 2 centrioles and are also an area where microtubules are produced
What are the types of endoplasmic reticulum? (2 types)
- Smooth ER (no ribosomes)
- Rough ER (ribosomes occur along the ER)
What are chromosomes composed of?
Chromosomes are composed of DNA and bound proteins (called histones)
What happens at the Rough ER and Golgi Apparatus? (6 steps)
- Protein synthesis takes place
- Information coded in DNA sequences in the nucleus is transcribed as messenger RNA (mRNA)
- Messenger RNA exits the nucleus through small pores to enter the cytoplasm
- The ribosomes on the rough ER translate the messenger RNA into proteins
- The proteins are transferred to the Golgi in “transport vesicles”
- The proteins are then processed and packaged into lysosomes, peroxisomes, or secretory vesicles
What is Rough ER?
Rough ER (rough appearance) due to the numerous ribosomes that occur along the ER
What is thylakoids?
An elaborate system of flattened membranous discs (chlorophyll are found here)
What is vacuoles?
Vacuoles are large membrane-bound fluid containing vesicles
What is mitochondria?
Mitochondria is the powerhouse of the cell as they generate “energy” for cell (ATP), and are also rich in enzymes and responsible for catabolism
What is microtubules?
They assemble into spindle structure that moves chromosomes during cell division
What does nucleus contain? (2 examples)
- Contains chromosomes
- Contains nucleolus
What are organelles?
- Organelles are internal membranes that are composed of the same material as the plasma membrane (predominantly phospholipids)
- Most organelles are bound or surrounded by membrane
What is peroxisomes?
Peroxisomes contain enzymes called peroxidase which break down hydrogen peroxide
What are some examples of membrane-bound organelles? (5 examples)
- Nucleus
- Endoplasmic Reticulum (Rough & Smooth)
- Golgi apparatus
- Mitochondria
- Lysosome
What is hydrogen peroxide (H2O2)?
Hydrogen peroxide are toxic to cells and are produced from metabolism and to kill invading organisms
What is nucleus?
Nucleus is the genetic control centre of the cell and the largest organelle
What separates the nucleoplasm from the cytoplasm?
Nucleus
What is ATP synthase and where is it located?
ATP synthase enzyme is located on the inner membrane (cristae) which synthesizes adenosine triphosphate (ATP)
What are some examples of fluid-containing vesicles?
Fluid contains water, gases, acids, salts, sugars, pigments and toxic waste
What are the functions of Smooth ER? (3 functions)
- Synthesizes lipids, steroids (estrogen & testosterone)
- Processes toxins and drugs in liver cells
- Stores and releases calcium ions in muscle cells (sarcoplasmic reticulum)
