The movement of water leads to dramatic changes in the volumes of the two compartments. Osmosis in red blood cells affects the tonicity of the cells. Tonicity refers to the ability of a solution to change the shape or tone of cells by altering the cells’ internal water volume (Marieb 2013). Changes in the concentration of water on either side of the cell membrane result in a net loss or gain of water by the cell (Marieb 2013). If cells are exposed to a solution that has the same solute/water concentration as inside the cells, the solution is said to be isotonic.
As sucrose enters the phloem the concentration of phloem sap increases. This causes the entry of water by osmosis from the surrounding cells 5. Water pressure is lower in the sink and therefore, this results in the water and dissolved solutes to flow towards a SINK 6. A sink is a region of the plant where sugars and other nutrients are actively being removed from the phloem. As sucrose moves out of the phloem sap and into surrounding cells (with energy), water flows out of them.
| | | C) | Osmotic pressure caused the cell to rupture. | | | D) | The cell was damaged by bacteria. | | | | | | Feedback: Since the cells are in a hypotonic solution, water entered by osmosis until the osmotic pressure ruptured the cell. | | 6 CORRECT | | The semifluid environment inside the plasma membrane is called ____. | | | A) | endoplastic reticulum | | | B) | microtubules | | | C) | cytoplasm | | | D) | mitochondria | | | | | | Feedback: The cell's chemical processes take place in a semifluid material called the cytoplasm.
The buffer solution is used to keep the pH of the experiment at a constant number while carrying ions that are essential to hold a current. Agarose is a polysaccharide usually extracted from algae. It comes in a powder but when mixed with boiling water and poured into the chamber it transforms into a gel. A comb is put into place before the Agarose is poured to allow wells where samples will be deposited when the Agarose hardens. When Agarose is in a gel state it is filled with tiny pores that allow molecules to pass through.
Place about one quarter of a ripe banana in a small resealable plastic bag. Seal the bag, and use your fingers to squash the banana until no visible chunks remain. 2. Use a graduated cylinder to measure 10 mL of the 0.9% NaCl solution, and add it to the bag. Mix thoroughly.
Plant Pigments Depending on Photosynthesis. Is the rate of photosynthesis faster when there are extreme light and temperatures present? Paper chromatography is a technique used for separating and identifying pigments. The solvent DPIP, (2, 6-dichlorophenol-indophenol), which is often used to substitute for NADPH, moves up the paper by capillary action. As the solvent moves up the paper, it carries along any substances dissolved in it, which are the pigments.
These dead cells are firmly attached to one another and are keratinised and they protect the living cells beneath them and help prevent water loss. b) How does the skin assist in body temperature control? • Sweat glands produce a liquid that is released through the pores in the epidermis. When this liquid is released on the surface of the body it evaporates and this in turn
Transfer the peanut butter that is now on the knife to one slice of bread and spread the scoop of peanut butter evenly on this slice with the knife. If more peanut butter is desired repeat taking the peanut butter from the jar and spreading it on the same slice of bread. Put the knife down off to the side. Put down the slice of bread with the peanut butter on it back on the plate, next to the other slice of bread, with the peanut butter side up. The third step is to clean the knife using the napkin and wipe it clean.
AP Biology November 3, 2011 Lab 1: Diffusion and Osmosis Objectives: * Measure the water potential of a substance in a controlled experiment. * Determine the osmotic concentration of living tissue or an unknown solution from experimental data * Describe the effects of water gain or loss in animal and plant cells * Release osmotic potential to solute concentration and water potential Introduction: Diffusion is the process that allows particles or molecules to move from an area of high concentration to an area of low concentration. This process accounts for the movement of many small molecules across cell membranes. The rate of diffusion of particles will be affected by the steepness of the concentration gradient or the difference in concentration between two areas. Diffusion can only occur across a membrane if there is a concentration gradient and the membrane is passable.
He tells us to cut it once and examine the colors again. We see some of his humor come thought when he says, “Structurally, the onion is not a ball, but a nested set of fingers within fingers, each thrust up from the base though the center of the one before it” (14). He uses this to paint a picture in your mind about when you get past the physical appearance and open something up, you realize that it is more complex. Next, the smell. It is a burning odor flowing from the onion that was cut and placed in front of you.