quiz seven - membranes II (active transport)

passive transport

no ATP cost, moves with concentration gradient

types of passive transport

diffusion, facilitated diffusion, osmosis

diffusion

small molecules can diffuse across phospholipid bilayer

facilitated diffusion

passive transport via transmembrane or carrier proteins

• allows larger/charged molecules to diffuse

active transport

requires ATP and carrier proteins, moves against concentration gradient

types of active transport

primary active transport and secondary active transport

primary active transport

uses ATP

secondary active transport

uses energy set up by direct active transport

types of transmembrane proteins

• channel protein

• carrier protein

channel protein

opening in center, can be gated

carrier protein

changes shape, one end open at a time

types of carrier proteins

• uniporter

• symporter

• antiporter

uniporter

carrier protein, one molecule in one direction

symporter

carrier protein, 2 molecules in same direction

antiporter

carrier protein, 2 molecules in opposite directions

describe H+ ATPase function in maltose transport

primary active transport, uses ATP, uniporter

• maintains optimal pH inside/outside cell, preventing proteins from denaturing (all proteins denatured = dead cell)

• creates H+ concentration gradient for maltose transporter to use

describe maltose permease function in maltose transport

also known as maltose transporter

secondary active transport, symporter

• powered by protein gradient made by H+ ATPase

• lets in maltose, glucose, pNPaG, but prefers maltose and glucose over pNPaG

maltase

enzyme that breaks down maltose → 2 glucose molecules

• enters yeast cell through maltose permease/transporter

yeast

• uses maltose as food source

• maltose can’t diffuse through membrane, so maltose permease/transporter transports it into the cell

• maltase breaks maltose → 2 glucose, which yeast cell uses

pNPaG breakdown

maltase breaks down pNPaG:

• pNPaG + maltase → pNP (p-nitrophenol) + glucose

pNP at pH 9

pNP (colorless) → phenolate ion (yellow green color)

pNPaG and maltose relationship

pNPaG is an analog of maltose

analog

a molecule whose structure is similar to that of another molecule

kidney functions - nephron

filtration, reabsorption, secretion

filtration of nephron

• occurs in Bowman’s capsule

• blood pressure forces fluid from glomerulus → capsule

• filtrate contains water, urea, amino acids, and ions

reabsorption of nephron

• occurs in proximal tubule, loop of Henle, distal tubule

• reclaims essential molecules back into bloodstream (ions, nutrients, water)

• maintains homeostasis

secretion of nephron

• adds additional wastes from blood into nephron tubule

• removes toxins, drugs, excess ions, and urea

calculating excretion of nephron

excretion = filtration - reabsorption + secretion

nephron

part of kidney, filters blood, reabsorbs what’s needed, secretes waste

name the parts of the kidney

name the parts of the kidney

name the parts of the nephron

explain maltose transport

explain the maltose transporter assay WITHOUT inhibitor

explain the maltose transporter assay WITH inhibitor

what was the substrate in the maltose transporter assay?

pNPaG

what was the inhibitor in the maltose transporter assay?

glucose