Cellular Biology Flashcards
What are the structural levels of the body?
Organelle = Subcellular structure made of molecules to perform specific job.
Cell = Smallest + most numerous structural + functional unit of life.
Tissue = group of cells with a similar structure that operate together as a unit.
Organ = structure made up of multiple types of tissue to perform a specific function.
System = tissues and organs that work together to perform a complicated task.
What is a cell?
The smallest structural + functional unit of life. Chemical reactions (metabolism) take place in the cell + where genome stored.
What are the roles of each system of the body?
Endocrine = Secrete chemical messengers into the blood.
Nervous = Transit messages between the brain and the rest of the body.
Respiratory = Supply oxygen to the blood and remove carbon dioxide.
Circulatory = Transport chemical messengers, respiratory gases, product of digestion, blood cells and waste round the body by pumping blood.
Digestive = Transfer nutrients to the body and absorb water whilst eliminating waste.
Integumentary = Regulates body temp. reduces water loss + protects the body from damage.
Lymphatic = Protect the body from infection.
Reproductive = Produce new life.
Urinary = eliminate waste products + preserve chemical and water balance.
Muscular = enable motion + thermal generation + push food through tract + pump heart.
Skeletal = enable motion when muscles contract.
What is the nucleus (S+F)?
Nucleus = the control centre of the cell.
Nucleoplasm = Thick liquid suspension - enables transportation + preserves shape and structure.
Nuclear envelope = Pored double membrane - separates contents + enables passage of some molecules.
Chromatin = DNA wound around histone proteins - Tightly coiled for storage + spreads out for division.
Nucleolus = Stores RNA to make ribosomes.
What are ribosomes (S+F)?
Free floating or attached to the Rough ER - Site of protein synthesis.
What are mitochondria (S+F)?
Rod or spherical shaped + folded inner membrane - Surface area (up) for aerobic respiration.
What is the Smooth ER (S+F)?
System of membranes with no ribosomes with surface area (up) + fluid filled cavities - Transport + synthesis + storage of carbohydrates and lipids.
What is the Rough ER (S+F)?
System of membranes studded with ribosomes with surface area (up) + fluid-filled cavities - Storage + transport + synthesis of proteins.
What is the Golgi apparatus (S+F)?
Stack of membrane-bound flattened sacs to and from which vesicles transport substances - Packages, modifies and transports proteins + lipids. Creates lysosomes.
What are lysosomes (S+F)?
Vesicles of membrane + contain hydrolytic enzymes (lysozymes) - breaks down cells in phagocytosis.
What is the Permanent vacuole (S+F)?
Fluids + sugars + amino acids stored and supports the cell when turgid.
What is the Cytoskeleton (S+F)?
Formed of (Tubulin tubes) microtubules + (Thread like Structural protein) filaments - Shape and strength to cell + transports organelle throughout the cell + anchors organelles..
What is the role of the plasma membrane?
Stop damaging particles entering and keep cytoplasm in + boundary between cell and environment + enable some molecules to pass through such as respiratory gases and nutrients.
What is the structure of the plasma membrane ?
Phospholipid heads are hydrophilic + tails are hydrophobic so form a phospholipid bilayer so small, polar molecules can pass through. Cholesterol regulates the fluidity of the bilayer.
Integral proteins (inserted into membrane) (Transport) of substances in and out through pumps or channels.
(Receptors) enable cells to recognise familiar or foreign cells.
Peripheral proteins (outside surface) -
Part of extracellular surface, surrounding + supporting cell or part of cytoskeleton on inside surface.
What are centrioles (S+F)?
Tubulin subunits at right angles to each other - form spindle fibres + found in centromeres.
