Unit 3 Lesson 2: What does in Must come out

Question 1

What are living things made of

Answer 1

cell

Question 2

Give an example of a single cell thing

Answer 2

They can be made of a single cell, such as a paramecium

Question 3

What does multicellular mean

Answer 3

made of many cells; like an elephant

Question 4

What does the cell membrane do and why dont living things melt

Answer 4

The cell membrane forms a barrier between the outside environment and the inside of a cell. Because it is made of two layers of lipids, the cell membrane is waterproof. This is why living things do not melt

Question 5

How many sides do lipid layers have

Answer 5

The lipid layers of the cell membrane have two sides to them.

Question 6

What is the first side of lipid layers called and where is it located

Answer 6

One side, called the hydrophilic head, points towards the outside of the bilayer.

Question 7

What does hydrophilic mean

Answer 7

water loving

Question 8

What is the other side of lipid layers called and where is it located

Answer 8

The other side, called the hydrophobic tail, points towards the center of the bilayer.

Question 9

What does hydrophobic mean

Answer 9

water fearing

Question 10

There are other structures in the cell membrane that help materials pass through. What are these structures

Answer 10

These structures include various proteins and aquaporins, which form tiny openings in the cell that allow certain materials to enter and exit the cell.

Question 11

What are aquapornics

Answer 11

the protein channels that allow water to enter and leave a cell

Question 12

What is concentration gradient

Answer 12

the gradual change in concentration of a solute in a solution

Question 13

What does concentration gradient refer to

Answer 13

This refers to the amount of a certain molecule in a specific location.

Question 14

What is diffusion

Answer 14

the movement of molecules from an area of higher concentration to an area of lower concentration

Question 15

What is an example of concentration gradient and diffusion (mose so concentration gradeint)

Answer 15

For example, when you add a drop of green food coloring into a glass of water, first you’ll see a high concentration of green color in the drop and a low concentration of color in the water. Over time, the color molecules spread out to completely fill the glass and the water is all the same green color.

Question 16

For example, when you add a drop of green food coloring into a glass of water, first you’ll see a high concentration of green color in the drop and a low concentration of color in the water. Over time, the color molecules spread out to completely fill the glass and the water is all the same green color. What is this movement of molecules called

Answer 16

This movement of molecules from an area of higher concentration to an area of lower concentration is called diffusion. Many different things diffuse across the cell membrane.

Question 17

Why can Oxygen and carbon dioxide move back and forth across the cell membrane at any time

Answer 17

Oxygen and carbon dioxide molecules are small enough to move back and forth across the cell membrane at any time.

Question 18

If there are a lot of oxygen molecules outside the cell and very few inside the cell; how will the movement of the oxygen molecules be

Answer 18

If there are a lot of oxygen molecules outside the cell and very few inside the cell, the oxygen molecules move from outside to inside.

Question 19

If there are more oxygen molecules inside the cell and very few outside the cell; How will the movement of the oxygen molelcules be

Answer 19

, the oxygen molecules move from inside to outside.

Question 20

What is the passive transport

Answer 20

If there are a lot of oxygen molecules outside the cell and very few inside the cell, the oxygen molecules move from outside to inside. If there are more oxygen molecules inside the cell and very few outside the cell, the oxygen molecules move from inside to outside. This is called passive transport

Question 21

What is the meaning of passive transport

Answer 21

the movement of molecules across the cell membrane without the need for energy; moving ions or molecules across cell membranes without the need for energy.

Question 22

Diffusion is a form of ..

Answer 22

passive transport

Question 23

Why is diffusion a form of passive transport

Answer 23

Diffusion is a form of passive transport. It is considered to be passive because it does not require any energy.

Question 24

How is the movement of water oin the moleclue

Answer 24

Water is another molecule that is always moving back and forth across the cell membrane.

Question 25

Hiw dies water move back and forth

Answer 25

Like oxygen, water can move at any time, but instead of diffusing directly through the cell membrane, water moves through tiny openings called aquaporins.

Question 26

What do Aquapornics do

Answer 26

Aquaporins control the movement of water into and out of the cell.

Question 27

water moves through tiny openings called aquaporins. Describe the diffusion

Answer 27

This type of diffusion, in which a protein is needed for the molecule to move from a high to a low concentration, is facilitated diffusion.

Question 28

What does facilitated diffusion mean

Answer 28

the diffusion of small, hydrophilic molecules across the cell membrane that requires a protein to help transport the molecule across the cell membrane

Question 29

The diffusion of water across a selectively permeable membrane (the cell membrane); What is this called

Answer 29

Osmosis

Question 30

What does osmosis mean

Answer 30

the diffusion of water molecules through a semipermeable membrane from higher concentration to lower concentration until equilibrium has been reached

Question 31

What does the Osmosis process relie on

Answer 31

Osmosis relies on the concentrations of solutes and solvents inside and outside the cell.

Question 32

What is a solute

Answer 32

a material that is dissolved in a solvent

Question 33

What is an example of a soulte

Answer 33

salt

Question 34

What is a solvent

Answer 34

A solvent is material that dissolves the solute.

Question 35

What are some examples os solutes in a cell

Answer 35

Solutes in a cell can include salts, sugar, magnesium, potassium, and other minerals.

Question 36

Wnhat are examples of solvents in cells

Answer 36

Solvents in a cell are usually water.

Question 37

What is a solution

Answer 37

The mixture formed by dissolving a solute into a solvent is a solution.

Question 38

What are solute and solvent concentrations always doing

Answer 38

Solute and solvent concentrations are always changing, and cells need to adjust to stay healthy.

Question 39

To determine the direction of water movement in osmois it is important to do what

Answer 39

To determine the direction of water movement in osmosis, it is important to compare the concentration of solutes in the two solutions.

Question 40

When observing osmosis you typically compare what what 2 things

Answer 40

When observing osmosis in cells, you typically compare the solution inside the cell to the solution in the environment around the cell.

Question 41

When the amount of solute inside the cell and outside the cell is equal, the environment is said to be..

Answer 41

isotonic

Question 42

What does isotonic mean

Answer 42

a solution with the same concentration of solutes compared to another solution. isotonic (iso means “the same”).

Question 43

What are the chararterstics of a isotonic enviroement

Answer 43

When the environment is isotonic there is no net movement of water across the membrane and the cell keeps its usual shape.

Question 44

What does no net movement mean

Answer 44

. It is important to note that no net movement does not mean that no water molecules are moving into or out of the cell. No net movement simply means that for every water molecule moving out of the cell, there is a water molecule moving into the cell. The flow is balanced.

Question 45

Describe a hypotonic enviroment

Answer 45

When there is more solute inside of the cell than outside, water from the outside moves into the cell to dilute the concentration. When this happens, the cell increases in size. In this case, the environment outside of the cell is called hypotonic

Question 46

What does hypotonic mean

Answer 46

a solution with lower concentration of solutes compared to another solution (hypo-means “less”)

Question 47

Describe an example where the outside of the cell is hypertonic

Answer 47

When there is more solute outside of the cell than inside (for example if a red blood cell were placed into a saltwater solution), water from inside of the cell moves out of the cell to dilute the concentration. When this happens, the cell decreases in size. In this case, the outside of the cell is called hypertonic (hyper- means “more”).

Question 48

What does hypertonic mean

Answer 48

a solution with higher concentration of solutes compared to another solution

Question 49

Hypertonic vs hypotonic

Answer 49

when you compare two solutions, the solution with a higher concentration of solute is called hypertonic while the solution with the lower concentration of solute is called hypotonic.

Question 50

If the two solute concentrations are equal, what will the soultion be

Answer 50

istonic

Question 51

water will awlays flow between what 2 solutions why is that

Answer 51

Water will always flow from the hypotonic solution to the hypertonic solution because hypotonic solutions have less solute and more water. Therefore, water flows from the area with more water to the area with less water. This flow of water continues until equilibrium is reached and the solutions are isotonic. At equilibrium, the flow of water into the cell is equal to the flow of water out of the cell.

Question 52

What enviroemnt do animal cells prefer

Answer 52

Animal cells, which do not have a cell wall, tend to prefer isotonic environments.

Question 53

What happenes to an animal cell in a hypotonic enviroment

Answer 53

When placed in hypotonic environments, they tend to take on too much water, which may cause them to burst or lyse.

Question 54

What happens to animla cells in hypertonic enviroments

Answer 54

When placed in hypertonic environments, they tend to lose too much water and shrivel.

Question 55

What eveiroments do plant cells prefer

Answer 55

Plant cells, which have a rigid cell wall, tend to prefer hypotonic environments.

Question 56

Excess water allows plant cells to do what

Answer 56

The excess water allows them to have turgor pressure

Question 57

What happens to plant cells in isotonic enviroments

Answer 57

When placed in isotonic environments, plant cells do not have enough water to maintain turgor pressure and they wilt.

Question 58

What happens to plant cells in hypertonic envrioments

Answer 58

When placed in hypertonic environments, plant cells lose too much water, causing the cell membrane to detach from the cell wall. This process, known as plasmolysis, is lethal to the plant cell.

Question 59

Howto move against the concentration gradient

Answer 59

The only way to move against the concentration gradient is to pump more molecules to areas where the concentration is already high.

Question 60

Give an example of moving aginst the concentration gradient

Answer 60

One example is the sodium-potassium pump. Sodium and potassium ions are electrically charged. When signals from the brain are carried around the body, they move across structures called neurons. For the signal to flow across the neuron membrane, sodium and potassium ions must quickly flow across its cell membrane. There are already ions on both sides of the neuron membrane, but more are needed to carry the signal.

Question 61

This movement of molecules that uses energy to move against their concentration gradient (from low to high) is called..

Answer 61

avtice transport

Question 62

What is active transport

Answer 62

the movement by energy of molecules across a cell membrane from low to high concentration

Question 63

Why cant proteins and waste leave the cells like water?

Answer 63

proteins made inside the cell need to be moved to other areas of the body to build structures such as muscle. Also, waste products that build up within the cell need to be removed, otherwise they will cause the cell to become unhealthy. These materials are too large to fit through the protein channels that cross the membrane and are way too big to diffuse through it without the aid of a protein.

Question 64

What does endocytosis mean

Answer 64

taking large materials into a cell

Question 65

What does exocytosis mean

Answer 65

moving large materials out of a cell

Question 66

endocytosis and exocytosis both require

Answer 66

Bulk transport in cells happens through either endocytosis or exocytosis. Both require energy because the cell membrane needs to alter its shape to allow for the large molecules.

Question 67

What kind of process is Endocytosis

Answer 67

Endocytosis is a type of active transport process.

Question 68

What is a vesicle

Answer 68

a small fluid filled sac within a cell

Question 69

What happens during endocytosis

Answer 69

During endocytosis, materials that are too large to fit through the protein channel openings in the cell membrane are approached by the cell. The cell membrane starts to extend around the molecules, trapping them inside a structure called a vesicle. The vesicle then starts to move away from the membrane toward another structure called a lysosome. Here, the vesicle membrane is dissolved, releasing the molecules inside the cell.

Question 70

What is the endocytosis opposite of

Answer 70

Exocytosis is the opposite of endocytosis.

Question 71

What happens during exocytosis

Answer 71

During exocytosis, large particles from within the cell, such as proteins or waste materials, are packaged into a vesicle. The vesicle then moves to the cell membrane where they join together. The outer edge of the vesicle/cell membrane complex bursts open, releasing the molecules into the external environment.

Question 72

How does hydrophilic compare to hydrophobic?

Answer 72

Hydrophilic refers to molecules that can dissolve in water. It comes from the Greek root hydr-, which means water, and the suffix -philic, which means loving. Hydrophobic refers to molecules that cannot dissolve in water. It comes from the Greek root hydr-, which means water, and the suffix -phobic, which means fearing. Something that is hydrophilic likes water while something that is hydrophobic dislikes water.

Question 73

What is the importance of a vesicle during bulk transport of molecules?

Answer 73

The vesicle is a small fluid filled sac that contains the molecules being moved. It travels from the cell membrane to inside of the cell during endocytosis and from the inside of the cell to the cell membrane during exocytosis.

Question 74

Summarize what happens to a red blood cell when placed into a very salty solution, which has a much higher concentration of solutes.

Answer 74

Water will move from inside of the cell to outside of the cell where the salt concentration is higher. The cell will shrivel due to the loss of water. Since the environment outside the cell has a higher solute concentration, it is hypertonic. This means the inside of the cell is hypotonic. Water always moves from a hypotonic to a hypertonic solution, so water will exit the cell. This is what causes the cell to shrivel.

Question 75

How does water get into and out of a cell?

Answer 75

Water moves across the cell membrane through tiny pores called aquaporins. Water moves through a type of diffusion called osmosis.

Question 76

Compare active transport with passive transport. Read each description and decide if it is active or passive transport.

requires energy
uses osmosis
molecules move against concentration gradient
uses a sodium/potassium pump
no energy required
molecules move with concentration gradient

Answer 76

requires energy: active transport
uses osmosis: passive transport
molecules move against concentration gradient: active transport
uses a sodium/potassium pump: active transport
no energy needed: passive transport
molecules move with concentration gradient: passive transport

Question 77

Infer why cells are almost always hypertonic to freshwater environments.

Answer 77

Cells are almost always hypertonic to freshwater environments because they contain more solutes than their surroundings. Cells contain salts, sugars, minerals, and other molecules.