Introduction to Cell Flashcards
What are the levels of organisation?
Chemical
Cellular
Tissue
Organ
System
Organism
What is a cell
- Basic structural and functional unit of an organism that is composed of chemicals
- facilitates functions, adapts (reproduction, movement, transport, protection
What is ATP?
Adenosine triphosphate.
(The energy of our body, energy required to function. Gotten from glucose)
How does a eukaryotic cell differ from a prokaryotic cell?
Eukaryotic - organelles, advanced, complex (fungi, plant and humans cells)
Prokaryotic - no nucleus, genetic material, unicellular organism (bacteria)
What is the plasma membrane?
- Forms cells flexible outer surface, separates cells internal/external
- Made of lipids, not soluble
- Selective barrier, regulates input/output, maintains environment
- Communication among cells
What is the cytoplasm?
- Consists of all cellular contents between plasma membrane and nucleus
- Cytosol and organelles
What is the cytosol?
- Intracellular fluid, 55% total cell volume
- 75-90% water, suspended components - ions, glucose, amino acids, fatty acids, proteins, lipids, ATP, waste
- site of chemical reactions required for cell’s existence
What is an organelle?
-Specialised structures within the cytosol
-Each type has characteristic shape and function in cellular growth, maintenance and reproduction
-Each has own set of enzymes that carry out specific reactions/functional compartment for specific biochemical processes
-Cooperating to maintain homeostasis
What is cytoskeleton?
- Network of proteins filaments that extend throughout cytosol
What does the centrosome do?
Creates pull within cell so it can be divided
What are the cilia and flagella?
Cilia - moves fluids over cell’s surface
Flagella - moves entire cell
What is the ribosome?
Synthesises protein when it leaves nucleus, then floats in cytoplasm
Wanders or attaches to Endoplasmic reticulum (rough)
What is the Endoplasmic reticulum?
Membrane enclosed passageway that transports materials
Proteins emerge from ER in small vesicles, Golgi body receives them, folds them into reusable products/added lipids/carbs
What is the Golgi Complex?
Activates protein created by the ribosome
What is the lysosome?
Digests things within cell
Vesicle formed from Golgi complex, contains digestive enzymes
What is the peroxisome?
Detoxifies harmful substances?
What is the mitochondrion?
Powerhouse of cell, provides energy
What is the nucleus?
- Large organelle that houses DNA (genetic material that dictates what cell does)
What are microfilaments?
-Composed of proteins actin and myosin
-Most prevalent at edge of cell
-Generates movement, mechanical support (muscles contracting, cell division and locomotion)
-Anchos cytoskeleton to integral proteins in plasma membrane
What are the intermediate filaments?
- Composed of several proteins, helps stabilise position of organelles and cells attach to one another
- Found in parts of cells subject to mechanical stress
What are microtubules?
- Long branches hollow tubes composed mainly of the protein tubulin, determines cell shape
- Begins in centrosome, grows outwards
- Function in movement of organelles
What is matter?
Anything that has mass and occupies space?
What does a state of matter depend on?
Temperature, surrounding pressure, strength of forces holding particles together
What are the 3 states of matter?
Solid, liquid, gas (indefinite shape and indefinite volume)
What are the properties of matter?
Physical property - observable characteristics without changing basic identity of substance (colour, physical state, melting/boiling point, hardness)
Chemical property - describes the way the substance undergoes or resists change to form a new substance. Ability to form a new substance (reaction/decomposition)
What is pure substance?
Only one substance present
Definite and constant composition
Properties always the same under same conditions
What are elements?
Cannot be broken down into smaller substance by chemical or physical means
Building blocks for all other types of matter
118 known elements
What is a compound?
Can be broken down into constituent elements by chemical means only
Has definite, constant elemental composition
What is a mixture?
Physical composition of two or more substances
Composition can vary
What is a homogenous mixture?
One visible phase
Same properties throughout
What is a heterogenous mixture?
Two or more visible phases
Different properties at different stages
What is the atomic number?
Number of protons
What is the mass number?
Number of protons and neutrons
What is the net charge?
How protons and electrons balance each other out. (Neutral - balanced)
What is an ion?
An atom what a net charge - positive or negative
Are electrons positive or negative?
Negative
What is an atom?
Smallest particle of an element that can exist and still have the properties of the element.
What are the atoms essential for life?
Carbon, hydrogen, nitrogen, oxygen
What are the subatomic particles?
Protons (+), electrons (-) and neutrons
What is a molecule?
Group of two or more atoms that function as unit, tightly bound. Same elements
What is the difference between a diatomic and homatomic molecule?
D - contains two atoms. H - all atoms are the same type of element
What is a compound?
Two of more atoms of different elements present tightly pound
What is an isotope?
Atoms of an element that have the same number of protons and the same number of electrons (but different number of neutrons). Same chemical properties, slightly diff physical properties. Naturally occur range from 2 to 10
