Week 2 - Organisation of the Cell Flashcards
1
Q
Cells
A
- Cells are the building blocks for all tissues in our body
- 37 trillion cells
- Shape of the cell determines role
- Work individually and together
- Two types are; sex cells and somatic cells
2
Q
Cell structure
A
Cell membrane Lysosome Nucleus Nucleolus Nuclear membrane Vacuole Mitochondria Golgi body Ribosomes Smooth ER Rough ER Cytoplasm Centrosome
3
Q
Cell membrane
A
- Lipid bilayer (2 layers of phospholipids)
- Physically isolates the intracellular environment from the extracellular environment
- It is semipermeable and allows substances to pass through the membrane
- It is highly sensitive to environmental changes (pH or chemical composition) and is the first line of defence
- Helps maintain the shape of the cell
4
Q
Cytoplasm
A
- The fluid containing organelles between cell membrane and nucleus
- Cytosol contains dissolved nutrients, proteins, ions and wastes
- Cytosol has high concentration of sodium ions
- Has a high concentration of proteins (enzymes) to help organelles complete specific functions
5
Q
Nucleus
A
- Processor of the cell
- Holds DNA code for all proteins
- Has a nuclear envelope to separate it from the cytosol
- Contains nuclear pores allowing chemicals to travel
- Fluid in nucleus is called nucleoplasm, which has filaments for structure
6
Q
DNA
A
- Genetic material of living organisms
- Organised into chromosomes
- Somatic cells have 23 pairs of chromosomes
- Coiled
- Instructs the cell on the proteins to make to achieve specific functions
7
Q
Endoplasmic reticulum
A
- Many proteins need help forming subsequent structures
- Membrane surrounded organelle that forms a tubular network that begins at nuclear envelope and extends into the cytosol
- Modifies proteins and helps produce carbohydrates/lipids
8
Q
Rough ER
A
- The protein that requires modification is fed directly from ribosome into here
- Has ribosomes attached to it
- Modifies proteins using an oxidative environment
- This environment allows proteins to fold properly and stabilises structure by forming intermolecular bonds
- Contains enzymes for production of lipid/carbohydrate products
- Helps detoxify using degradative enzymes. Sending basic constituents back to the cell or into the body for excretion
- An area of storage for cytoplasmic molecules
9
Q
Smooth ER
A
- Makes lipids and carbohydrates
- Has no ribosomes attached
10
Q
Lysosomes
A
- Functions to remove wastes
- Enclosed in a membrane
- They digest excess or worn out organelles, food particles, and engulfed viruses or bacteria
11
Q
Peroxisomes
A
- Present in cytoplasm
- Contains reducing enzyme catalase
- Absorb the nutrients that the cell has acquired
- Digests fatty acids and alcohols
- More present in the liver cells
12
Q
Mitochondria
A
- Site of major ATP production
- 2 membranes
- Inner membrane is heavily folded full of hydrogen ions that are critical to producing ATP. Also provides a large surface area when electrons of citric acid cycle and electron transport chain are fixed
- Contains enzymes to catabolise carbohydrates, proteins and lipids
13
Q
Golgi body
A
- Modifies and packages hormones and enzymes for secretion
- Packaging enzymes in vesicles for use in cytosol
- Maintains cell membrane
14
Q
Secretory vesicles
A
- Vesicles fuse with lipid bilayer to pass contents outside the cell
- Highly concentrated products to cell membrane
15
Q
Membrane renewal vesicles
A
- Can be shipped from golgi apparatus to the lipid bilayer to fuse with cell membrane
- This helps repair cell membrane from constant damage
- It helps assist change fluidity of cell membrane to allow certain materials to enter cell
