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BIO 251 EXAM 1 NEWEST 2024-2025 ACTUAL EXAM
COMPLETE 100 QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS )
|ALREADY GRADED A+
What is active transport? - ANSWER- the movement of ions or molecules across a cell membrane into a region of higher concentration, assisted by enzymes and requiring energy.
What is passive transport? - ANSWER- movement from high to low, no energy required
What is simple diffusion? - ANSWER- passive transport directly through the lipid bilayer
What is facilitated diffusion? - ANSWER- passive transport through carrier protiens
what is an ion channel? - ANSWER- transmembrane protein that allows diffusion of specific ions across the membrane
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Ion channels can exist in two configurations - ANSWER- open and closed state
what is a leak channel? - ANSWER- constantly open allowing passage of ions
what is a gated channel? - ANSWER- closed until stimulated to open
What is a ligand-gated ion channel? - ANSWER- closed until a specific chemical binds to open channel
What is a voltage gated channel? - ANSWER- closed until membrane potential reaches certain voltage
what is mechanical gated channel? - ANSWER- mechanical force causes gate to open
What is affinity? - ANSWER- binding strength
What is a symporter? - ANSWER- move molecules in the same direction
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what is an anti porter? - ANSWER- moves molecules in oposite directions
what is a gap junction? - ANSWER- channels formed between two cells via connexons
What is a chemical messenger? - ANSWER- any compound that serves to transmit a message
What is an autocrine? - ANSWER- when released binds to receptor on the same cell that released it
What is paracrine? - ANSWER- acts on the neighboring cell
what is endocrine? - ANSWER- Involves the release of a chemical signal into the blood
What are neurotransmitters? - ANSWER- messenger of the nervous system
What are cytokines? - ANSWER- can be transported in the blood, most act on neighboring cells, released by most cell types
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