Science C2

Question 1

describe the cell as an open system

Answer 1

it exchanges matter and energy within its environment so that it may acquire nutrients, excretes wastes and other cellular products. This is controlled by the cell membrane

Question 2

describe tonicity; hypertonic, isotonic, and hypotonic solutions and their effects on the movement of materials through membranes (water), including those of cells.

Answer 2

in a hypertonic- water would move out of the cell

Question 3

the membrane is

Answer 3

selectively permeable to maintain equilibrium/homeostasis

Question 4

the membrane contains

Answer 4

a phospholipid bilayer and proteins

Question 5

passive transport

Answer 5

uses kinetic energy, particle movement from an area of higher concentration to an area of lower concentration. Also the movement of substances through the cell membrane without the use of cellular energy.

Question 6

Active Transport

Answer 6

requires energy to move particles (ATP) which is created through cellular respiration. Particles move from areas of low to high concentration.

Question 7

Concentration Gradient

Answer 7

A difference in concentration of molecules. No extra energy (ATP) is required to move molecules down (with) a gradient; from an area of high to low concentration. Energy is required to move molecules up (against) a gradient; from an area of low to high concentration.

Question 8

Diffusion

Answer 8

Type of passive transport; movement of particles from an area of higher concentration to an area of lower concentration through vesicles. Diffusion continues until all particles are evenly spread out; are in equilibrium. The rate of diffusion can be increased by adding energy and increasing molecular movement. (heating or stirring)

Question 9

Osmosis

Answer 9

the diffusion of water across a membrane that is

permeable to water, but not the solute (semi-permeable). (high to low), (Passive transport).

Question 10

Tonicity

Answer 10

refers to the concentration of a solution in comparison

to that of another.

Question 11

Isotonic

Answer 11

= same as cell (Doesn’t change the shape of a cell) equal salt and water concentration

Question 12

Hypotonic

Answer 12

= less solute, more water (turgid). Causes cell to swell through osmosis.

Question 13

Hypertonic

Answer 13

= more solute, less water. Causes cell to shrink

Question 14

Facilitated diffusion

Answer 14

the movement from higher to lower concentration, but with proteins facilitating the movement. (Water-soluble
substance need assistance in the form of a protein channel or carrier protein in order to move across the cell membrane.) (Doesn’t need energy).

Question 15

Active Transport with Carrier Proteins (protein pump)

Answer 15

Similar to facilitated diffusion, but requiring energy to move molecules from a low to a high concentration.
May bring needed entities into the cell or expel materials from the cell.

Question 16

Endocytosis

Answer 16

Process by which a cell takes in material by forming a vacuole/membrane around it. Require energy from ATP for the rearrangement of the cell membrane.

Question 17

Types of Endocytosis: Phagocytosis and Pinocytosis

Answer 17

Phagocytosis involves the intake of larger molecules (cell eating). Pinocytosis is the engulfment of liquid and dissolved molecules (cell drinking).

Question 18

Exocytosis

Answer 18

Active transport that uses vesicles to remove wastes and cell products from a cell. Requires energy from ATP for the rearrangement of the cell membrane.

Question 19

Transport Protein

Answer 19

Used to help substances enter or exit cell membrane

Question 20

Carrier protein

Answer 20

transport protein that changes shape when a particle binds with it. Pump that helps move materials from low to high con.

Question 21

Channel protein

Answer 21

Transport protein that provides a tube-like opening in the plasma membrane through which particles can diffuse.

Question 22

Protein pump

Answer 22

capable of pumping out compounds that could pose a threat to the cell.

Question 23

Phospholipid

Answer 23

Made of a phosphate head and a fatty tail. The head loves water, tail hates water.

Question 24

(READ) If a cell wants to move a substance from an area with a LOW concentration to an area of HIGH concentration, it needs to use ENERGY to PUMP the substance AGAINST its CONCENTRATION GRADIENT.

Answer 24

This is called active transport and uses carrier proteins and ATP (energy)

Question 25

Peritoneal dialysis (membrane tech)

Answer 25

Peritoneal dialysis uses the peritoneal membrane to remove/filter out solutes and water from the body fluids of patients with end-stage renal disease.

Question 26

Observation from iodine and starch lab

Answer 26

The bag is permeable to iodine, but not to the starch. Starch is a bigger molecule while iodine isn’t so iodine is more permeable

Question 27

Observation from egg lab

Answer 27

The syrup solution was more concentrated so the egg shrunk. The water solution was less concerned and had more water so the egg expanded