Cell Structure and Function

Reading quiz (list your answers and correct answers from exam first) List the 3 components of the cell theory You have a cube with length of 1 cm. Explain

how to find the volume and the total surface area of the cube. Find each of the values (remember your units).

Cell theory

All living things are composed of cell

Cells are the basic units of structure and function in living things

New cells are produced from existing cells

What do cells do?

Carry out the processes of life: reproduction (only some cells), convert chemical compounds to usable energy, respond to the environment, grow and develop, maintain a stable internal environment, change

The cell works together to carry out these functions

Cells are specialized Cells are compartmented

Nucleus vs. Organelle vs. cytoplasm

What kinds of cells are there?Prokaryotic (lack true nucleus)

UnicellularEukaryotic (true nucleus)Unicellular or multicellular

Animal

Plant

Chromosome structure

Limits to cell growth 1) Not enough copies of DNA to serve large cell 2) Rate of nutrient exchange would decrease Surface area to volume ratio

Surface area

Volume

SA:V

Organelle Function Plant or animal cell

1.Nucleus Stores DNA Both

2. Ribosome Protein synthesis Both

3. Mitochondria Converts sugar to usable energy Both

4. Chloroplast Converts light to sugar Plant

5. Lysosome Digests materials Both

6. Vacuole Stores materials (mostly water) Both

7. Golgi apparatus Modifies proteins Both

8. Endoplasmic reticulm

Transports materials, lipid synthesis

Both

9. Cell membrane Regulates what goes in and out of the cell

Both

10. Cell wall Barrier, keeps shape plant

Sample process Cells often need to make proteins (for

example insulin) to transport somewhere else in the body

1. DNA in nucleus gives instruction for making the protein insulin

2. Protein is made at Ribosomes attached to the Rough Endoplasmic Reticulum

3. Protein is modified in the golgi apparatus

4. Protein moves in a vesicle and is released outside the cell

Reading quiz

1. What happens during the S phase of the cell cycle?

2. Cancer is essentially a disorder of what cell process?

3. What is the function of spindles? 4. In mitosis the ____ is divided in half while

in cytokinesis the ____ is divided in half 5. Explain how to identify a cell in

metaphase

Reading quiz 1. What happens during the S phase of the cell

cycle? DNA is replicated 2. Cancer is essentially a disorder of what cell

process? Cell division or mitosis 3. What is the function of spindles? Attach to or

move chromosomes 4. In mitosis the genetic material is divided in half

while in cytokinesis the cytoplasm is divided in half 5. Explain how to identify a cell in metaphase

chromosomes are lined up along the equator

Cell cycle

What is everything that happens during a cell cycle?

Do all cells divide at the same rate?

What controls when a cell divides?

What happens when a cell stops responding to these controls?

Cell cycle control

G1 checkpoint S, G2, M

No G1 checkpoint G0

Cancer growth

Mitosis and cytokinesis

Interphase: Cell grows and replicates its DNA

Prophase: Chromatin condenses, centrioles separate, spindle forms

Metaphase: Chromosomes line up at center

Mitosis and cytokinesis

Anaphase: Sister chromatids separate

Telophase: Chromosomes gather at either end

Cytokinesis: Cytoplasm separated, daughter cells have identical set of chromosomes