Cell biology Flashcards
What are the 6 most common elements in organic molecules
- oxygen
- carbon
- hydrogen
- nitrogen
- phosphorous
- sulphur
Define tissue
Groups of cells with interconnected function
Define organ
Structures consisting of at least two tissue types which perform a specific function related to the whole body
What are organ systems?
Groups of organs performing related functions allowing maintenance of homeostasis
What is the general physiology of cells?
- Respiration to make ATP
- Exchange gasses
- Divide and grow
- Secrete useful/important proteins
- Communicate with other cells
What features are in the general anatomy of cells?
- Phospholipid cell membrane
- Membrane bound organelles and nucleus
- Cytoskeleton
- Cytoplasm/cytosol
What is the function of the nucleolus?
The site where ribosomes are made and transported out into the cytoplasm
What are the functions of the phospholipid bilayer?
- Control movement of substances in and out
- Keep atoms and molecules at optimum conc. in and out of cell
- Needed by all cells to perform specialised function
What is the phospholipid bilayer permeable to?
- Water
- Small molecules (e.g. gasses)
What is the phospholipid bilayer impermeable to?
- Ions - repelled by hydrophobic fatty acids
- Large molecules (e.g. glucose)
What are the roles of membrane proteins?
- Control transport of ions/larger molecules in and out of cell
- Intercellular communication
- Let cells respond to stimuliW
What are electrolytes?
Substances in our diet which dissolve/disassociate into their ionic forms in water, allowing us to have the ions our body needs for functioning
What are the 4 important ions in cellular physiology?
- Sodium (Na+)
- Calcium (Ca+)
- Potassium (K+)
- Bicarbonate (HCO3)
What is the role of sodium in the body?
- Maintaining extracellular fluid volume
- Regulating membrane potential of cells (needed for neuron excitability)
Main;y extracellular
What is the role of potassium in the body?
Regulating membrane potential of cells (needed for repolarisation)
Mainly intracellular
What is the role of calcium in the body?
- Skeletal mineralisation
- Muscle contraction
- Synaptic transmission
- Blood clotting
Mainly extracellular
What is the role of bicarbonate in the body
- Buffer to keep pH neutral for most cell reactions to occur by binding to excess hydrogen ions produced in cellular reactions
Mainly extracellular
What is plasmolysis?
Changes in ion conc. leading to water being drawn into or out of a cell
What is CFTR
Defect in Cystic Fibrosis Transmembrane Regulator protein resulting in cystic fibrosis by preventing Cl- moving out of the cell, so water moves in by osmosis and mucus on cell surface membrane dries up
What are the different types of intercellular signalling?
- Endocrine signalling
- Paracrine signalling (nearby cell)
- Autocrine signalling (targets itself)
- Synaptic signalling
- Cell membrane protein signalling (direct contact)
What happens in intracellular signaling?
Receptor on cell surface sends signal to nucleus to switch on genes
Can be targeted by drugs (e.g. in tumour growth)
