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Homiostasis and transportation
Unit 4: Welcome
Objective
Describe how the structure of the plasma membrane allows it to function as a regulatory structure and/or protective barrier for a cell.
Compare the mechanisms that transport materials across the plasma membrane (i.e., passive transport—diffusion, osmosis, facilitated diffusion; and active transport—pumps, endocytosis, exocytosis).
Describe how membrane-bound cellular organelles (e.g., endoplasmic reticulum, Golgi apparatus) facilitate the transport of materials within a cell.
Explain how organisms maintain homeostasis (e.g., thermoregulation, water regulation, oxygen regulation).
Unit 4: Inner_about
Essential Quesions
How does the plasma membrane function as a regulatory structure and/or protective barrier for the cell?
What are the differences and similarities between diffusion, osmosis, facilitated diffusion; and active transport- pumps, endocytosis, exocytosis?
How do membrane-bound cellular organelles facilitate transport of material within a cell?
How do organisms maintain homeostasis?
Unit 4: About
Key terms and Definitions
Active transport
the movement of ions or molecules across a cell membrane into a region of higher concentration, assisted by enzymes and requiring energy.
Cell
the smallest structural and functional unit of an organism, typically microscopic and consisting of cytoplasm and a nucleus enclosed in a membrane. Microscopic organisms typically consist of a single cell, which is either eukaryotic or prokaryotic.
Concentration
Concentration refers to the amount of a substance per defined space.
Diffusion
the spreading of something more widely.
Endocytosis
the taking in of matter by a living cell by invagination of its membrane to form a vacuole.
Endoplasmic reticulum
a network of membranous tubules within the cytoplasm of a eukaryotic cell, continuous with the nuclear membrane. It usually has ribosomes attached and is involved in protein and lipid synthesis.
Exocytosis
a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane
Facilitated diffusion
Golgi apparatus
a complex of vesicles and folded membranes within the cytoplasm of most eukaryotic cells, involved in secretion and intracellular transport.
Homeostasis
the tendency toward a relatively stable equilibrium between interdependent elements, especially as maintained by physiological processes.
Impermeable
not allowing fluid to pass through.
Lipids
any of a class of organic compounds that are fatty acids or their derivatives and are insoluble in water but soluble in organic solvents. They include many natural oils, waxes, and steroids.
Osmosis
a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus equalizing the concentrations on each side of the membrane.
Passive transport
transport of a substance across a cell membrane by diffusion
Plasma membrane
a microscopic membrane of lipids and proteins which forms the external boundary of the cytoplasm of a cell or encloses a vacuole, and regulates the passage of molecules in and out of the cytoplasm.
Protein
any of a class of nitrogenous organic compounds that consist of large molecules composed of one or more long chains of amino acids and are an essential part of all living organisms
Ribosome
a minute particle consisting of RNA and associated proteins found in large numbers in the cytoplasm of living cells. They bind messenger RNA and transfer RNA to synthesize polypeptides and proteins.
System
a set of things working together as parts of a mechanism or an interconnecting network.
Unit 4: About
Summary
The primary function of the plasma membrane is to protect the cell from its surroundings. Composed of a phospholipid bilayer with embedded proteins, the plasma membrane is selectively permeable to ions and organic molecules and regulates the movement of substances in and out of cells. And the similarities passive and active transport are similar because they are moving molecules or whatever around in the cell. And the differences are passive transport, requires no energy for the things to pass through the cell. Each type of passive transport begins because there is a concentration gradient so the molecule moves across the membrane until equilibrium is met. Different from passive transport, active transport requires energy and Active transport moves against the concentration gradient so it does not end with equilibrium being met.And organisism maintain homeostasis by thermoregulation which is the regulation of the body temperture and this is done because it regulates the body’t temperture to kepp your body at a constant rate to keep you internally stable.
Unit 4: About
Multiple choice Question
What is the movement of osmosis across the membrane?
Unit 4: Event
A
food
B
energy
C
solute
D
Water
short answer question
How do membrane-bound cellular organelles facilitate transport of material within a cell?
Unit 4: Inner_about
Answer key
Multiple choices question to answer / Short question answerÂ
1. CÂ
And the similarities passive and active transport are similar because they are moving molecules or whatever around in the cell. And the differences are passive transport, requires no energy for the things to pass through the cell. Each type of passive transport begins because there is a concentration gradient so the molecule move across the membrane until equilibrium is met. Different from passive transport, active transport requires energy and Active transport moves against the concentration gradient so it does not end with equilibrium being met.
Unit 4: About
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