Cell Structure And Organisation🦠 Flashcards
1
Q
What is a eukaryote?🐯🌱
A
Any organism consisting of one or more cells that contain DNA in a membrane bound nucleus separate from the cytoplasm.
Large number of specialised membrane bound organelles.
2
Q
What is a prokaryote?🔍
A
Has DNA suspended freely in cytoplasm.
Is simple and lacks membrane bound organelles.
3
Q
Features of prokaryotes 🔍
A
- Peptidoglycan cell wall
- DNA suspended
- Ribosomes
- Cytoplasm
- Cell membrane with a phospholipid bilayer
- Mesosome for cellular respiration
- Capsule
- Sometimes have a flagellum
4
Q
Features of eukaryotes🐯🌱
A
Membrane bound organelles Mitochondria ER Ribosomes Golgi body Lysosomes Centrioles Nucleus Nucleolus Nuclear envelope Chromatin Plasmodesmata🌱 Chloroplasts🌱
5
Q
Features of plant cells (in comparison to animal cells)🌱
A
Cellulose cell wall Plasmodesmata Chloroplasts Large, permanent vacuole filled with cell sap Tonoplast Starch grains for storage No centrioles
6
Q
Features of animal cells (in comparison to plant cells)🐯
A
No cell wall No plasmodesmata No chloroplasts Small, temporary vacuoles No tonoplast Glycogen granules for storage Centrioles
7
Q
Plasma membrane
A
- Composed of a phospholipid bilayer with intrinsic and extrinsic proteins.
- Selectively permeable and controls movement of substances in an out of cell.
- Maintains different concentrations of molecules/ions inside and outside the cell.
- Gives the cell structure.
8
Q
Cell wall
A
- Bacteria: murein/peptidoglycan🔍
- Plants: cellulose🌱
- Fungi: chitin🍄
- Provides support.
- Keeps plant cell rigid and stops it from bursting.
- Allows plants to become turgid during osmosis.
- Permeable.
- Pores called plasmodesmata which allows the cytoplasm of neighbouring cells to connect, enabling exchange of substances.
9
Q
Nucleus
A
- Contains cell DNA which is passed on through generations and a provides coding for protein synthesis by making RNA.
- Nuclear membrane✉️ which enclose the nucleus. It has nuclear pores which allow RNA to leave the nucleus
- Nucleoplasm contains the cells DNA in the form of chromatin
- Nucleolus produces rRNA
10
Q
Ribosomes
A
- Made up of protein and rRNA
- Protein synthesis
- Synthesise enzymes
11
Q
Rough ER
A
- A series of double membranes with cisternae between
- Transports proteins
- Has ribosomes along its length which carry out protein synthesis
12
Q
Smooth ER
A
- A series of double membranes with cisternae between
* Synthesis of lipids
13
Q
Golgi body/Golgi apparatus
A
- A stack of flattened membranous sacs
- Assembles glycoproteins
- Produces lysosomes
- Modifies and packages proteins
- Transports and stores lipids
- Produces digestive enzymes
14
Q
Describe the process of the exportation of proteins by the Golgi body
A
- Vesicles containing proteins formed by the RER fuse at the end of the Golgi sacs
- The protein is modified inside the Golgi sacs
- The modifies protein is budded off in a vesicle at the other end of the Golgi sacs
- The vesicle travels to the outer plasma membrane where the protein is released by exocytosis
15
Q
What are lysosomes?
A
- Vesicles which contain digestive enzymes
- Has a membrane which prevents the enzymes digesting the cell itself
- Destroy worn out organelles
- Digest material taken into the cell, such as bacteria
- The material is taken into the cell and trapped in vacuoles which the lysosomes then fuse with to release their enzymes into them
16
Q
Mitochondria
A
- Release chemical energy in the form of ATP during aerobic respiration
- Double membrane
- Inner membrane is folded to form the cristae which increase the S.A on which ATP synthesis can occur
- Filled with matrix which contains ribosomes and mitochondrial DNA
