Basic Cell Structure Flashcards
Label all structures the structures A-H seen in the image.
A: cytoplasm
B: lysosome
C: Golgi Complex
D: mitochondria
E: Endoplasmic reticulum
F: Nucleus
G: Plasma Membrane
H: Ribosome
State the structure, function and disease associated with an error in the:
- Nucleus
Nucleus
Structure: Stained spherical structure that acts as the cell’s control centre.
Functions:
- DNA synthesis & repair,
- RNA synthesis,
- RNA processing & ribosome assembly.
Disease Associated:
- Alzheimer’s disease
- Parkinson’s disease
- Huntington’s disease
State the structure and function of the following structures:
- Nucleolus
- Nuclear envelope
Nucleolus
Structure : Darker stained circular region with the nucleus (centre of nucleus)
Function : Ribosome synthesis
Nuclear membrane/envelope
Structure: Partially permeable double-membrane.
Function: Has nuclear pores for the passage of substances
State the structure, function and the disease associated with an error in the:
- Cytoplasm
Cytoplasm
Structure: Contains enzymes, cellular organlles, and amino acids. Primarily made out of water.
Function: Cell morphology & movement.
Disease:
- Hunter’s disease
- Faybry disease
- Krabbe disease
State the structure, function and the disease associated with an error in the:
- Ribosomes
Ribosomes
Structure: Tiny circular structures which:
- attahced to the rER
- lie freely in the cytoplasm
Function: Protein synthesis
Disease:
- Bone marrow failure
- Diamond blackfin anaemia
- Cancer
- Dyskeratosis congenita
Distinguish between free and bound polyribosomes in terms of protein production.
- Free polyribosomes synthesise proteins which remain in the cytoplasm
- Bound polyribosomes show protein synthesis and segregation into the rough ER
State the structure, function and the disease associated with an error in the:
- Plasma membrane
Plasma membrane
Structure: Partially permeable membrane that encloses contents of cells
Function:
- Regulates export of proteins (secretory vesicles)
- Transport of ions and small molecules
–
- Selective permeability
- Transport of materials along cell surface
- Endocytosis and exocytosis
- Intercellular recognition
- Barrier to water-soluble molecules
–
Disease:
- Alzheimer’s disease
- Sickle cell anaemia
Describe the structure of plasma membranes.
- Composed of a phospholipid bilayer
- Hydrophilic heads, hydrophobic tails
- Associated membrane proteins: Integral and peripheral proteins
Outline 4 features of the Fluid Mosaic Model
- Hydrophobic fatty acid tails in the middle
- Hydrophilic heads on the outside
- Membrane proteins: integral proteins, peripheral proteins
- Phospholipids form a bi-layer
State the structure and function of the following:
- sER
- rER
Smooth ER
Structure : Network of tubes and flat curved sacs
Function:
- Detoxification reactions
- Fatty acid synthesis
- Lipid & steroid synthesis
Rough ER
Structure: Folded membranes studded with ribosomes
Function: Site of protein/membrane synthesis
Describe the structure of the endoplasmic reticulum.
- ER membrane is continuous and encloses a single lumen
- sER does not have ribosomes attached
- rER has ribosomes attached
State the structure and function of the following:
- Lysosome
Lysosome
Structure: Generated by the Golgi Apparatus
Funtion: Produces hydrolytic enzymes that aid in digesyion and excretion of substances
Distinguish between primary and secondary lysosomes in terms of their formation and function.
Primary lysosome:
I. Formed from the Golgi apparatus
II. Does not release intracellular contents
Secondary lysosome:
I. Formed by the fusion of the primary lysosome and an endocytotic/phagocytotic vesicle
II. Releases intracellular contents/waste products
State the structure and function of the following:
- Golgi complex
Golgi complex
Organelle that processes, modifies and repackages proteins produced in the rER for release at the cell membrane via secretory vesicles
State the structure and function of the following:
- Microtubules
- Centriole
- Microvillii
Microtubules : part of the cell’s cytoskeleton, aid movement of substances through cytoplasm
Centriole: composed of two cylinders of tubules; essential to cell reproduction
Microvilli: projections which increase the cell’s surface area
State the structure and function of the following:
- Microfilament
- Vacuole
- Cytoskeleton
Microfilament: provides support for the cell; sometimes linked to cell’s outer membrane
Vacuole: sac that stores and transport ingested materials, waste products and water
Cytoskeleton: internal framework of the cell, made up of microfilaments and hollow microtubules
Describe the structure and function of mitochondria.
Mitochondrion
Double-membraned organlle where energy is released. Contains circular DNA, 70S ribosomes
- Site of ATP synthesis for metabolic reactions (oxidative phosphorylation)
- Metabolism of carbohydrates, amino acids, and nucleotides
How are mitochondrias inherited?
Female lineage
What are the two types of chromatin?
Euchromatin and Heterochromatin
Euchromatin
- does no stain strongly, lighter packaging
Heterochromatin
- stains more intensely, indicating tighter packing
What is limit of resolution?
Limit of resolution – the minimum distance at which two objects can be distinguished
Outline the general structure of prokaryotic cells.
- Prokaryotic cells have an external membrane but no internal membranes
- All the biochemical processes of the cell occur in the same compartment
Identify 7 primary components of the prokaryotic cell
- Capsule
- Cell wall
- Plasma membrane
- Flagella
- 70s Ribosomes
- Nucleoid
- Pili
Outline the general structure of a eukaryotic cell.
- Eukaryotic cells are compartmentalised by internal membranes.
- Hence, eukaryotic cells have a true nucleus and true organelles
Identify 10 primary components of the eukaryotic cell.
- Plasma membrane
- Vacuole
- Nuclear envelope
- Nucleolus
- Chromosomes
- Lysosome
- ER (rER and sER)
- Golgi Complex
- Free ribosomes
- Mitochondria
What is glycocalyx?
- The glycocalyx is the cell coat
- It is made up of oligosaccharide and polysaccharide side chains on the outside of the plasma membrane
Identify 4 functions of the cytoskeleton
- Determines the shape of animal cells
- Ensures movement of cells
- Structural support and movement of cell organelles
- Provides the framework for moving and separating cells during cell division
What are microtubules?
Microtubules are long hollow cylinders made of the protein tubulin
Where are microtubules found?
Sites where structures are moved (i.e. nerve fibres, the mitotic spindle, cilia and flagella)
How do bacterial, plant and mammalian cells differ in terms of:
- Cell Wall
Plant: Cellulose cell walls
Animals: None
Bacterial: Murein cell walls
How do bacterial, plant and animal cells differ in terms of:
- Cell Nucleus
Plant: Controls activity of the cell. Each nucleus surrounded by a double membrane that has nuclear pores.
Animal: Most have nucleus (except RBCs - refered to as anucleated cells). Some have >1 nuclei (hepatocytes, refered to as coenocytes).
Bacterial: None
How do bacterial, plant and animal cells differ in terms of:
- Plasmids
Plant: None
Animal: None
Bacterial: Present. Plasmid is a molecule of DNA that can replicate independently. Double-stranded, circular and capable of replicating within a suitable host.
How do bacterial, plant and animal cells differ in terms of:
- Mitochondria
Plant + Animal: Present. Outer membrane is smooth. Inner membrane folds to form cristae, increases the inner membrane’s surface area. Site of ATP synthesis, metabolism of carbohydrates, amino acids & nucleotides
Bacterial: None
How do bacterial, plant and animal cells differ in terms of:
- Ribosomes
Plant + Animal: 80S ribosomes. Site of protein synthesis. Can exist as free ribosomes or are attached to the rER. Made in the nucleolus.
Bacterial: 70S ribosomes.
How do bacterial, plant and animal cells differ in terms of:
- Chloroplasts
Plant: Choloroplasts are present and contain the pigment chlorophyll.
Animal: None
Bacterial: None
How do bacterial, plant and animal cells differ in terms of:
- Permanent Vacuole
Plant: Large central permenant vacuole. Contains cell sap; water ions etc. Mains turgidity of the cell.
Animal : None
Bacterial : None
Identify the following structures:
- Heterochromatin
- Zymogen granules
- Nuclear envelope
- rER
Identify the following structure from this micrograph:
- Cytoplasmic extension (CE)
- Pinocytic vesicle (PV)
- Golgi body (G)
- Lysosome (L)
- Nucleolus
