SECTION B CELL Flashcards
What is a cell?
The basic structural and functional unit of living organisms.
Where are organelles found?
within the cytoplasm
What 4 structures are found in both plant and animal cells?
- cell membrane or plasma membrane
- cytoplasm
- nucleus
- mitochondria
What 3 structures are found in plant cells only?
- cell wall made of cellulose
- chloroplasts
- a large vacuole
Can you compare plant and animal cell?
- Have cell wall made of cellulose.
Does not have cell wall. - Have chloroplasts containing chlorophyll.
Does not have chloroplasts containing chlorophyll. - Have one large central vacuole.
Vacuoles are small and scattered through the cytoplasm. - Contains starch grains as food store.
Contains glycogen granules as food. store. - Have a regular shape, usually round, square or rectangular.
Can have a great variety of different shapes.
What are microbes?
Microbes are microorganisms that include all members of the Prokaryotae kingdom and many members of the Protoctista Kingdom (ameoba) and some members of the Fungi kingdom (yeast).
Can you discuss cell specialization?
The body of a unicellular organism consists of one unspecialized cell. This cell carries out all essential life processes.
The body of a multicellular organism is composed of many cells. To enable multicellular organisms to carry out all essential life processes efficiently, cells become specialized to carry out specific functions, example muscle cells contract to bring about movement and mesophyll cells in leaves carry out photosynthesis. By becoming specialized, cells are better able to carry out their specific functions.
Cells specialized to carry out a particular function work together in groups called tissues. Different tissues are then grouped together to form specialized organs which may perform one or more functions, example the skin is composed of epithelial, connective and nervous tissue and the leaves of plant are composed of epidermal and vascular tissues. Organs work together in organ systems, example the digestive, nervous and blood vascular system in animals and transpiration and translocation system in plants. Systems work together in an organized way to form a multicellular organism.
What is a tissue?
A tissue is a group of cells that work together to perform a particular function.
cell membrane?
- Separates the interior of all cells from the outside environment which protects the cell from its environment.
- The cell membrane consists of a lipid bilayer that is semipermeable. The cell membrane regulates the transport of materials like nutrients entering and materials like waste exiting the cell.
- Active transport
Reference to the cell membrane as a differentially permeable membrane, contrast with cell wall which is freely permeable.
cell wall?
Freely permeable made of cellulose.
- Supports and protects the cell.
- Gives the cell its shape.
- It controls intercellular transport. Turgor pressure.
chloroplasts and mitochondria?
Organelles that capture and release energy. These 2 organelles have their own DNA.
Chloroplasts are disc-shaped organelles.
- Contain chlorophyll.
- Site where photosynthesis occurs.
Mitochondria are rod-shaped organelles
- Generate chemical energy needed to power cell reactions - produce ATP.
- Site where respiration occurs.
- Contain respiratory enzymes.
starch grains?
food store
plant vacuole?
Large membrane-bound organelle containing cell sap.
- Supports the cell when turgid.
- May store food or cell waste.
animal vacuole?
Small and membrane-bound sacs.
- Important in endocytosis and exocytosis.
- Store waste products and prevents cell contamination.
contractile vacuole?
Saclike osmoregulatory organelle of amoeba.
Controls the intracellular water balance by accumulating and expelling excess water out of the cell, allowing cells to survive under hypotonic stress as in pond water.
nuclear membrane?
- Separates the nucleus from the cytoplasm.
2. Controls what goes in and out of the nucleus.
nucleus?
A double membrane-bound organelle that controls the activities of the cell.
- Contains the genetic information of the cell in the form of DNA.
- Controls the characteristics and functioning of the cell (growth and metabolism).
- Site of RNA production.
nucleoid?
A single, long and coiled loop of DNA. Controls all cellular activities.
cytoplasm?
Jelly-like fluid inside the cell.
- Holds and supports the organelles of the cell providing a a platform upon which organelles can operate within the cell.
- Protects organelles from damage.
- Meditates the entry and exit of substances, example cellular contents between the plasma membrane and nucleus, including cytosol.
glycogen granules?
food store
capsule?
A slimy outer layer that surrounds the cell walls of some bacteria, protecting the cell surface and sometimes helping to glue the cell to surfaces.
plasmid?
Small, circular piece of DNA located in the cytoplasm of many bacteria.
flagellum?
Long, whip-like structure.
Aids in movement.
pseudopodium?
A cellular extension of amoeboid cells.
- Used to engulf food for feeding.
- Aid in movement.