Filtration & Diffusion + Dialysis and Cell Transport

IN LAB YOU TESTED THE RATE OF DIFFUSION OF POTASSIUM PERMANGANATE AND METHYLENE BLUE THROUGH AGAR. WHICH DYE MIGRATED AT A SLOWER RATE? WHY?

Methylene blue = <1mm / 30 min = <0.03mm / min; Therefore potassium permanganate has lower molecular weight than methylene blue

IN LAB YOU OBSERVED THE PROCESS OF FILTRATION OF A SOLUTION CONTAINING STARCH, COPPER SULFATE AND CHARCOAL. ____________________ DID NOT PASS THROUGH THE FILTER PAPER. WHY?

charcoal is retained (retentate); Filtration relies on pore size, the size of the substance to be filtered, and the hydrostatic pressure differential between both sides of the filter.

THE RATE OF DIFFUSION OF POTASSIUM PERMANGANATE AND METHYLENE BLUE THROUGH AGAR IS DIFFERENT,WHY?

Therefore potassium permanganate has lower molecular weight than methylene blue

IN LAB YOU OBSERVED THE PROCESS OF FILTRATION OF A SOLUTION CONTAINING STARCH, COPPER SULFATE AND CHARCOAL. NOT ALL OF THE SUBSTANCES PASSED THROUGH THE FILTER PAPER. WHICH DID NOT PASS THROUGH? WHY?

charcoal is retained (retentate); Here we can see as iodine is added to the filter paper, it turns dark purple confirming the presence of starch; Filtration relies on pore size, the size of the substance to be filtered, and the hydrostatic pressure differential between both sides of the filter.

HOW WAS THE PRESENCE OF CHARCOL ON THE FILTRATION MEMBRANE VERIFIED?

with the naked eye

HOW WAS THE PRESENCE OF COPPER SULFATE IN THE FILTRTION BEAKER VERIFIED?

Copper Sulfate was seen in the beaker, seen as a blue fluid.

WHAT WAS USED TO TEST FOR THE PRESENCE OF STARCH ON THE FILTRATION PAPER?

using Iodine

WHAT COLOR WAS SEEN WHEN THE IODINE WAS PLACED ON THE FILTRATION PAPER?

dark purple

WHAT COLOR WAS SEEN WHEN THE IODINE WAS PLACED IN THE FILTRATION BEAKER?

remains brown

DOES POTASSIUM PERMANGANATE DIFFUSE FASTER THROUGH LIQUID (WATER) OR SOLID (AGAR)

liquid is much faster than in solid medium

IN LAB, USING DIALYSIS TUBING AND METHYLENE BLUE, DOES METHYLENE BLUE STAY INSIDE THE TUBING OR EXIT?

starts to dialyze out of the sac into the water

IN LAB, USING DIALYSIS TUBING AND METHYLENE BLUE, WHY DOES METHYLENE BLUE EXIT THE TUBING

methylene blue is also small enough to fit thru the pores (<14Kd MW)

IN LAB, USING DIALYSIS TUBING, DID BLUE DEXTRAN EXIT THE TUBING? WHY?

The MWCO of this dialysis tubing is 14Kd (14,000 MW). Molecules smaller than this will go thru the pores; blue dextran MW is >14Kd.

______________ IS THE CRINKLING-UP PROCESS OBSERVED IN RED BLOOD CELLS PLACED IN A HYPERTONIC SOLUTION / RBC LOSING WATER

Crenation

IN ACTIVE PROCESSES____________ DRIVES MOVEMENT THROUGH THE PLASMA MEMBRANE

ATP

IN PASSIVE PROCESSES____________ DRIVES MOVEMENT THROUGH THE PLASMA MEMBRANE

concentration (gradient) or pressure difference

WHAT KIND OF ENERGY DO MOLECULES POSSESS THAT KEEP THEM IN CONSTANT MOTION?

kinetic energy

A DIFFERENCE IN CONCENTRATION ACROSS A MEMBRANE IS CALLED?

Concentration Gradient

__________ IS USED TO APPROXIMATE A SEMI-PERMEABLE MEMBRANE WHEN USING BLUE DEXTRAN/ METHYLENE BLUE

Dialysis tubing

__________ IS A PASSIVE PROCESS BY WHICH WATER AND SOLUTES ARE FORCED THROUGH A MEMBANE BY HYDROSTATIC (FLUID) PRESSURE

Filtration

WHAT WAS USED AS A SEMI-PERMEABLE MEMBRANE DURING THE FILTRATION EXERCISE?

Whatman #2 filter paper

THIS STRUCTURE LABELED "A" WITH THE PINK TAPE WAS USED DURING WHICH EXERCISE?

Filtration

THE RATE OF DIFFUSION IS GREATER IN WHICH MEDIA: LIQUID OR SOLID?

liquid is much faster than in solid medium

IN LAB, USING DIALYSIS TUBING AND BLUE DEXTRAN, YOU TESTED______________.

tonicity

IN YOUR HOMEWORK YOU TESTED THE MOVEMENT OF SODIUM AND POTASSIUM ACROSS A SELECTIVELY PERMEABLE MEMBRANE BY ______________________.

Active Transport

WHEN PLACED IN A HYPOTONIC SOLUTION, RED BLOOD CELLS WILL BURST, A PROCESS KNOWN AS _______________.

Hemolysis

IN LAB, USING DIALYSIS TUBING, WATER WENT IN OR OUT OF THE TUBING WITH BLUE DEXTRAN? WHY?

Water will enter the area with more solute, inside the tubing.

WHAT IS THE ROLE OF ATP IN ACTIVE TRANSPORT?

Driven directly by ATP

WHEN RED BLOOD CELLS ARE PLACED IN A HYPOTONIC SOLUTION THEY WILL BURST. WHY?

This is due to osmotic pressure being greater than the cell membrane can hold, thus the outward pressure exerted on the cell membrane from within exceeds the membrane’s strength

WHEN PLACED IN A_______ SOLUTION, RED BLOOD CELLS WILL BURST (HEMOLYSIS)

Hypotonic

IN LAB, USING DIALYSIS TUBING AND METHYLENE BLUE, YOU TESTED______________.

Dialysis

WHEN PLACED IN A ___________________ SOLUTION RED BLOOD CELLS WILL SHRINK, A PROCESS KNOWN AS_____________.

Hypertonic; Crenation

WHAT IS THE SIMPLE DIFFUSION OF WATER THROUGH A MEMBRANE CALLED?

Osmosis

WHY DO RED BLOOD CELLS SHRINK WHEN PLACED IN A HYPERTONIC SOLUTION?

Crenation is the loss of water till the cell shrinks or crenates.

____________ IS THE BURSTING OF RED BLOOD CELLS AS WATER FLOODS INTO THEM

Hemolysis

EXPLAIN WHEN HEMOLYSIS OCCURS.

Hemolysis- red blood cells burst.

EXPLAIN WHEN CRENATION OCCURS

Crenation is the loss of water till the cell shrinks or crenates.

LARGE MOLECULES AND MOLECULES ARE TRANSPORTED ACROSS THE MEMBRANE BY _______________

Facilitated Diffusion

MOVEMENT OF MOLECULES THROUGH A MEBRANE AND INTO THE CELL IS CALLED?

Endocytosis is movement into the cell.

MOVEMENT OF MOLECULES THROUGH A MEBRANE AND OUT OF THE CELL IS CALLED?

Exocytosis is ejection of materials from the cell

IN ____________, THE CELL MEMBRANE SINKS BENEATH MATERIAL TO FORM A SMALL VESICLE, WHICH THEN PINCHES OFF INTO THE CELL INTERIOR

Pinocytosis

IN ____________, PARTS OF THE PLASMA MEMBRANE AND CYTOPLASM EXPAND AND FLOW AROUND A RELATIVELY LARGE OR SOLID MATERIAL

Phagocytosis

WHAT IS THE MEMBRANOUS SAC FORMED DURING PHAGOCYTOSIS?

phagosome

WHAT IS THE SELECTIVE TYPE OF ENDOCYTOSIS THAT USES PLASMA MEMBRANE RECEPTORS?

Receptor-Mediated Endocytosis

WHAT MEDIUM WAS USED TO SHOW DIFFUSION THROUGH A SOLID?

agar

THE ____________ OF A DIALYSIS MEMBRANE REFERS TO THE MAXIMUM SIZE OF MOLECULES THAT WILL BE ALLOWED TO PASS THROUGH ITS PORES

molecular weight cut off (MWCO)