Flashcards
Cell Theory and Prokaryotic Cells
Flashcards do conjunto (28)
- 1Outline the cell theory1. All living things are composed of cells (or cell products)
2. The cell is the smallest unit of life
3. Cells only arise from pre-existing cells - 2Unicellular organisms carry out all the functions of lifeMovement
Reproduction
Sensitivity
Growth
Respiration
Excretion
Nutrition - 3MovementLiving things show movement, either externally or internally
- 4ReproductionLiving things produce offspring, either sexually or asexually
- 5SensitivityLiving things can respond to and interact with the environment
- 6GrowthLiving things can grow or change size / shape
- 7RespirationLiving things use substances from the environment to make energy
- 8ExcretionLiving things exhibit the removal of wastes
- 9NutritionLiving things exchange materials and gases with the environment
- 10Importance of the surface area to volume ratio as a factor limiting cell sizeThe rate of metabolism of a cell and
the rate of material exchange in and out of a cell is a function of its surface area
As the cell grows, volume increases faster than surface area (leading to a decreased SA:Vol ratio) - 11Multicellular organisms show emergent propertiesEmergent properties arise from the interaction of component parts, that whole is greater than the sum of its parts
Multicellular organisms are capable of completing functions that individual cells could not undertake - this is due to the interaction between cells producing new functions
Cells to tissues, to organs, to organ systems to organism - 12Cells in multicellular organisms differentiate to carry out specialised functions by expressing some of their genes and not othersAll cells of an individual organisms share an identical genome, each cell contains the entire set of genetic instructions for that organism
The activation of different instructions (genes) within a cell by chemical signals will cause it to differentiate from other similar cells
Differentiation is the process during development where newly formed cells become specialised and distinct from one another as they develop
Active genes are packaged in an expanded and accessible form (euchromatin), while inactive genes are mainly packaged in a condensed form (heterochromatin) - 13Stem cells retain the capacity to divide and have the ability to differentiate along different pathwaysStem cells are unspecialised cells that have two key qualities of self renewal and potency.
- 14Self renewal of stem cellsAbility to continuously divide and replicate
- 15Potency of stem cellsAbility to differentiate into specialised cell types
- 16Therapeutic process in the use of stem cellsStem cells can be used to replace damaged or diseased cells with healthy and functioning ones
This process requires the use of biochemical solutions to trigger differentiation into a desired cell type, the surgical implantation of cells into the patient's own tissue, and careful monitoring of the new cells to ensure they do not become cancerous - 17Therapeutic use of stem cellsNerve cells, to repair damage caused by spinal injuries to enable paralysed victims to regain movement
Blood cells, used for bone marrow transplants in cancer patients who are immuno-compromised as a result of chemotherapy - 18Cell WallCell outer layer made of peptidoglycan that maintains shape and protects the cell from damage or bursting if internal pressure is high
- 19Cell MembraneSemi-permeable barrier that controls the entry and exit of substances
- 20CytoplasmFluid component which contains the enzymes needed for all metabolic reactions
- 21NucleoidRegion of the cytoplasm which contains DNA
- 22Prokaryotic RibosomeComplexes of RNA and protein that are responsible for polypeptide synthesis (70S)
- 23FlagellaLong thread-like structure which enables cell mobility
- 24PiliHair-like extensions found on bacteria
- 25Attachment PiliAllow bacteria to adhere to one another or to available surfaces
- 26Sex PiliAllow the exchange of genetic material (plasmids) through a process called bacterial conjugation
- 27How do prokaryotic cells divide?Binary Fission
- 28Binary FissionBinary fission is a form of asexual reproduction and cell division used by prokaryotic cells. The process of binary fission includes circular DNA that is copied in response to a replication signal, the two DNA loops attach to the membrane, which elongates and pinches off, forming two separate cells
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- IB Biology (Cells) FlashCards sobre Cell Theory and Prokaryotic Cells, criado por Alex Snellgrove em 12-11-2014.
- Criado por
- Alex Snellgrove
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