24/02 Flashcards
What defines life?
Cellular organisation, cellular reproduction, genetic information system, growth and development, metabolic systems, display homeostasis, sensitivity to the environment, evolutionary adaptation
What is an obligate parasite?
A virus, incapable of replicating outside of a cell
What are the main points of cell theory?
All organisms are composed of cells, cells are the smallest living things, cells originate from pre-existing cells, cells contain genetic information, cells have a boundary, cells can be differentiated into types, cells can self nourish and cooperate
Define prokaryotes.
Unicellular organisms that lack a defined nucleus and membrane enclosed organelles
What is the structure of prokaryotic cells?
Genetic material in nucleoid region, lack organelles, free-floating ribosomes, enclosed by plasma membrane, cell wall for structural shape, flagella for locomotion
What distinguishes eukaryotic cells from prokaryotic cells?
Eukaryotic cells possess a membrane-bound nucleus and membrane-bound organelles
What is the endomembrane system?
A series of membranes throughout the cytoplasm that divides the cell into compartments for different functions
What is the function of the nucleus in a eukaryotic cell?
Contains genetic material in DNA and acts as the control center
What does the Golgi apparatus do?
Synthesises carbohydrates, modifies proteins and lipids before exiting the cell
What is the main function of mitochondria?
Produces ATP by cellular respiration
Fill in the blank: The _______ is responsible for photosynthesis in plant cells.
Chloroplast
What are the basic structural similarities between prokaryotic and eukaryotic cells?
Cell membrane, genetic material, cytoplasm, cytoskeleton, ribosomes
What is the endosymbiosis theory?
The theory that eukaryotic cells evolved from symbiotic associations with prokaryotic cells
What are the main components of animal cells that are not found in plant cells?
Lysosomes, centrosomes with centrioles, flagella
What is the function of the central vacuole in plant cells?
Storage, waste breakdown, and creating internal turgor pressure for structural support
True or False: The cytoskeleton is static and does not change.
False
What is the role of the cytoskeleton in animal cells?
Gives shape, provides scaffolding, structural support, and motility
What does the term ‘turgidity’ refer to in plant cells?
Internal turgor pressure created by the central vacuole for structural support
