Cell Transport and Division

Rebecca Maloney, Ciara O’Shea, Madeleine Skipworth, Will Rips, Jonathan Wakeman

Period 1

Passive Transport

• Movement of material down the concentration gradient

• Does NOT require energy from the cell• Diffusion– The movement of random particles down the

concentration gradient to achieve equilibrium• Osmosis– The movement of water to create equilibrium

Diffusion• Facilitated Diffusion– Passive transport by proteins (no energy required)– Channel Proteins• Form channels to

allow specific molecules to flow through

– Carrier Proteins• Change shape to

allow a substance to pass through the membrane

Diffusion

• Isotonic– The [solutes] and [water] inside and outside the

cell are the same• Hypotonic– the [solutes] outside the cell lower than inside the

cell. The [water] is higher outside the cell.• Hypertonic– The [solutes] outside the cell is higher than inside

the cell. The [water] is lower outside the cell

Active Transport

• Movement of materials though a membrane AGAINST a concentration gradient– Requires energy from cell

Transport of Large Molecules

• Endocytosis- the process by which a cell surrounds and takes in material from its environment.(engulfea)

• Exocytosis- the expulsion or secretion of materials from a cell.

• Diffusion

• Osmosis

Cell Cycle

• The life cycle of a cell; events when the cell grows and divides

Mitosis

• Interphase– When the cell grows and replicates its DNA and

centrioles

• Prophase– Chromatin condenses into chromosomes.

Centrioles separate, and a spindle forms. The nuclear envelope begins to break down

Mitosis

• Metaphase– Chromosomes line up across the center of the cell.

Each one is connected to a spindle fiver at its centromere

• Anaphase– The sister chromatids separate into individual

chromosomes and are moved apart

Mitosis

• Telophase– The chromosomes gather at opposite ends of the

cell, the chromosomes begin to loose their definite shape

• Cytokinesis– The cytoplasm pinches in half, each daughter cell

has an identical set of chromosomes

Control of Cell Cycle

• Enzymes work to monitor a cells progress from phase to phase during the cell cycle

• Some enzymes work to replicate DNA, some begin cell division, and others control the rest of the cell cycle

Cancer

• A mistake in the cell cycle• Cancer is the result of uncontrolled cell

division caused by genetic and environmental factors

• Uncontrolled cell division occurs when– Cells fail to produce certain enzymes– Enzymes are over produced– Enzymes are produced at the wrong time

Stages of Cancer

• Cancer cells result from a change in one or more genes

• Form masses of tissue called tumors that deprive normal cells of nutrients

• Later cancer can enter the circulatory system and spread throughout the body

Question 1

Passive transport is the movement of materials _________ the concentration gradient.

a. Throughb. Againstc. Downd. Up

Question 2

Osmosis if the movement of ________ to create equilibrium.

a. Waterb. Particlesc. Moleculesd. Cells

Question 3

What is the correct order of the cell cycle?

a. G1, G2, S, Mb. M, S, G1, G2c. S, G1, M, G2d. M, G1, S, G2

Question 4

Which phase is this?

a. Metaphaseb. Anaphasec. Prophased. Telophase

Question 5

Which type of transport requires energy?

a. Activeb. Passive

Question 6

What is the first stage of mitosis?

a. Interphaseb. Prophasec. Anaphased. Cytokinesis

Question 7

________ solution: the [solutes] outside the cell is lower than inside the cell.

a. Isotonicb. Hypertonicc. Hypotonic

Question 8

What does [x] mean?

Question 9

Cancer is the result of what?

Question 10

What is one example of uncontrolled cell division?

Answer Key1. C2. A3. D4. A5. A6. B7. C8. Concentration of x9. Uncontrolled cell division

10. Cells fail to produce certain enzymes/ enzymes are overproduced/ enzymes are produced at the wrong time