G’s Flashcards
Passive (5) VS active transport (8)
PASSIVE:
- no energy (ATP)
- [High] to [low]
- With [] gradient
- Osmosis diffusion
- Facilitated diffusion
ACTIVE:
- Energy (ATP)
- [low] to [high]
- Against the [] gradient
- Endocytosis: phagocytosis or pinocytosis
- Exocytosis
- Na+/K+ pump
What is a selectively permeable membrane? (6)
-Somethings can pass through it and others cannot (depending upon the size etc..) selects in 6 ways:
- diffusion (no energy)
- osmosis (no energy)
- Facilitated transport (no energy)
- Active transport (energy)
- Endocytosis (energy)
- Exocytosis (energy)
What is diffusion? What are the ways to increase the rate of diffusion? (7)
DIFFUSION:
- particles moving from [high] to [low] until it is equally distributed
INCREASING RATE OF DIFFUSION:
1. Increasing temperature.
2. Increasing surface area.
3. Changing in shape and size of a molecule. (Smaller particles, diffuse faster)
4. Changing in concentration gradient. (Bigger gradient = faster diffusion)
5. High pressure + agitation (stirring)
6. Electricity
7. Enzymes (catalyst)
Examples of diffusion? (4)
- alcohols (can dissolve in phospholipids)
- Gases (O2, CO2)
- Water (osmosis)
- Small molecules
What is osmosis? What are examples of osmosis?
OSMOSIS:
- H2O passively going from [high] to [low] across a selectively permeable membrane until evenly distributed.
EXAMPLES OF OSMOSIS:
- H2O observed by large intestines and kidneys
What is facilitated transport? What are examples of facilitated transport? (2)
FACILITATED TRANSPORT:
- Passive type of transport that requires no energy going from [high] to [low] where molecules that are not normally able to pass through the lipid membrane can pass through via carrier proteins (the proteins can change their shape and size as it passes through)
EXAMPLES:
- Glucose and amino acids
What does active transport? What are examples of active transport? (4)
ACTIVE TRANSPORT:
- “cell pumping” An active type of transport, where they move from [low] to [high] against a concentration gradient
EXAMPLES:
- Na+/K+ pump
What is endocytosis? What are the three types of endocytosis and their examples? (4)
ENDOCYTOSIS:
- Actively taking in of molecules by indentation of the cell membrane forming a vesicle
TYPES:
- phagocytosis: “cell eating/ packman” large particles ex: white blood cell amoeba
- Pinocytosis: “cell drinking/ sipping” small particles, or liquids ex: blood cells, plant root cells
- receptor-mediated endocytosis: a form of pinocytosis with receptor proteins ** very specific
What is exocytosis? What are examples of exocytosis? (3)
EXOCYTOSIS:
- The reverse of endocytosis, vacuole/vesicle fuses with the cell membrane and dumps contents outside ex: (secretory, vesicles dumping out, hormones into blood, enzymes in digestive systems and pancreatic cells)
What is tonicity?
- The strength of a solution in the amount of solutes
What is an isotonic solution?
- Where the solution concentration is equal on both sides of the membrane as the water moves in and out equally so they sell routines, normal shape and size
What is a hypertonic solution? (2)
- TOO MANY SOLUTES
- Where the solution outside is more concentrated than the inside, causing water to move out of the cell (osmosis) causing Crenation in animal cells in plasmolysis in plant cells —> (cell membrane pulled away from the cell wall, causing so to lose its rigidity)
What is a hypotonic solution? (2)
- TOO LITTLE SOLUTES
- where the concentration inside the cell is more concentrated than the outside, causing water to move into the cell where the cell can potentially burst, causing lysis in animal cells and turgor pressure (turgid) in plant cells
What is the surface area to volume ratio important in cells? What are examples of high surface area in cells? (3)
- The size of the surface area is important for the amount of material entering and leaving the cells as high surface area equals high efficiency/reaction rate
EXAMPLES: - Alveoli in lungs
- microvilli in intestines
- Mitochondria Cristae
Gift for functions for proteins in the cell membranes, one function for carbohydrate, chains, and one function for cholesterol
Proteins:
- Transport Proteins that facilitate the movement of molecules across the membrane
- Receptor proteins that allow the cell to respond to external stimuli
- Enzymatic Proteins that Catalyze specific chemical reactions
- Cell Recognition Proteins: Identify cells as belonging to a particular organism
- Carbohydrate chains play a key role cell to cell ID
- Cholesterol aids in stability by regulating fluidity
