Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
18 Cards in this Set
- Front
- Back
|
Why are all structures in eukaryotic cells membrane-bound |
They can all have their own internal environments So they are more efficient |
|
|
What is the structure of the Nucleus and what is its purpose? |
- Double membrane: the second is more efficient communication with RER, the first is where reactions occur. Controls the cell through DNA expression - Nuclear pores: Communication with the cell - Nucleolus: Sores DNA, manufactures RNA and ribosomes |
|
|
What is the structure of the mitochondrion and what is its purpose? |
- Double membrane: Outer to control the environment, inner folded into a cristae for more manufacture of ATP - Matrix: Where the ribosomes and DNA are stored |
|
|
What is the structure of RER and what are their purpose? |
- Made of flattened tubules and sacs: Is a pathway for transport - A double membrane covered in ribosomes - It synthesises proteins and glycoproteins - It synthesises and transports enzymes |
|
|
What is the structure of SER and what are their purpose |
- Made of tubules and a double membrane (no sacs) - It synthesises materials such as lipids - It is a pathway for lipids and carbohydrates |
|
|
What is the structure of the Golgi apparatus and what are their purpose? |
- Flattened sacs and cisternae (flattened discs): Transport - A double membrane: Produces secretory enzymes, modifies lipids and proteins, synthesises lysosomes, "labels" proteins, lipids - Vesicles (small fluid filled bladders): Transports enzymes to the surface |
|
|
What is the structure of lysosomes and what are their purpose? |
- Pockets of degenerative enzymes in a membrane in the cytoplasm, used for: - Hydrolysing: Breaking apart stuff ingested by phagocytes (cells that engulf bacteria and small stuff) - Autolysis: Breaking down dead cells - Breaking down non-functioning old organelles - Exocytosis: Releasing enzymes out of the cell |
|
|
What is the structure of ribosomes and what are their purpose? |
- Made of RNA and protein, found on RER - Used in protein synthesis in translation |
|
|
What is the structure of chloroplasts and what are their purpose? |
- A double membrane - Grada -> stacks of thylakoids -> contain chlorophyll: Used for photosynthesis - A matrix with DNA and ribosomes |
|
|
What is the structure of the cell wall and what is its purpose? |
- Made of microfibrils (small fibres) of cellulose. Gives: - Structural integrity - Controls movement of water into and out of the cell |
|
|
What is the structure of the vacuole and what is its purpose? |
- A sac of fluid in a tenoplast - Provides structural support - Stores sugars, amino acids, waste products, pigments - This is a temporary food source - In flowers the pigments attract insects |
|
|
What is the structure of a chloroplast and what is its purpose? |
- A double membrane - Grada -> stacks of thylakoids -> contain chlorophyll - A matrix with ribosomes and DNA |
|
|
What is the matrix in chloroplasts called? |
The stroma |
|
|
What organelle do prokaryotic cells lack when compared to eukaryotes? |
Mitochondria |
|
|
What is the cell membrane mostly made of? |
Phospholipids |
|
|
What reasons might a cell need many mitochondria? |
- Active transport - Movement - Making other substances |
|
|
Describe how a protein is made and moved out of a cell |
- An mRNA copy of the desired DNA is made in the nucleus - This then exits the nucleus through the nuclear pores - mRNA attaches to ribosomes on the RERand assembles the protein - The RER (sometimes) modifies the protein, packages it, and transports it to the Golgi apparatus - It is then modified, labelled, and sent off in vesicles - The vesicles fuse with the plasma membrane, and the protein is released |
|
|
What does cell specialisation do? |
Makes cells more efficient |
