a. smallest unit that has all the characteristics of life 1. grow 2. respond to a stimuli

A. Smallest unit that has ALL the characteristics of life1. Grow2. Respond to a stimuli3. Reproduce4. Metabolism5. Move6. Homeostasis

Cells – The Basic Unit of Life

B. Several types of cells1. Variety of shapes2. Variety of sizes

Cell structure determines functionCell function determines structure

C. Functions of the cell

1. Basic unit of life2. Protection & support3. Movement4. Communication5. Cell metabolism & energy release

D. 70 – 80% WaterE. Two areas of water

Intracellular-inside the cellExtracellular- outside the cell

1. Extracellular►Thick, syrup-like liquid

►Mixture of dissolved gases, salts, food & cellular products

manufactured or synthesized by mechanisms inside the cell, which

leave by secretion.

ex. hormones, vitamins, & proteins

Types

A. Contained within blood vessels & chambers of the heart

Plasma -liquid medium for transport (Oxygen, wastes, &

nutrients).

B. Interstitial FluidPathway for products that are in

route between cells.

C. Extracellular Matrix---ECM---composed of proteins and polysaccharides

Purpose of ECM- Structural support for the body

Other Functions

2. Intracellular Environment

Between Cells

► Protoplasm or Cytoplasm► Components –

Water Fats

Proteins Nucleic Acids Carbohydrates

Electrolytes

When the components are organized in such a way you get:

Characteristics of life

Boundary of the cell or Cell (Plasma) Membrane

►3 major components inside the cell1. Intracellular fluid - cytoplasm or

protoplasm2. Organelles - small membrane

bound vessels3. Nucleus - regulates the cell

activities

Review

►Name three characteristics of life?

►How is intracellular material different from extracellular material?

►How is interstitial fluid different from extracellular fluid?

II. Cell MembraneA. Bilipid layer

1. Composed of two phosolipids layers2. Glycoproteins

3. Proteinsa. Integralb. Peripheral

4. Cholesterol5. Glycolipids

6. Membrane receptors7. Carrier molecules

8. Receptor molecules

B. Fluid Mosaic Model

C. Semi Permeable- Selective permeable

Not everything can pass through the cell membrane.

2. Materials that pass with easea. Water

b. Small lipid soluble moleculesc. Small non charged particles

3. Materials that have difficulty passing:

a. Larger molecules (lipid soluble or non lipid soluble)

b. Charged particlesc. Need carrier proteins to

pass through the cell membrane.

4. Two ways materials can pass through the cell membranea. Passive – no energy required

Following a concentration gradient from high to low to establish equilibrium.

Majority of life’s process.

b. Active – requires energy

Going against the concentration gradient trying NOT to establish a equilibrium

Nerve cells

5. Ways that material can pass through the cell membrane.

a. Directlyb. Membrane channels

c. Carrier moleculesd. Vesicles

Review

►Describe the structure of the cell membrane.

►What function does it perform?►How do lipid-soluble molecules, small

molecules and large molecules that are not lipid base cross the cell membrane?

►How is passive movement different from active movement?

D. Types of Passive movement1. Simple Diffusion - Following a concentration

gradient from high to low to establish equilibrium.

Small lipid soluble & Non charged particles

2. Facilitated Diffusion Following a concentration gradient

from high to low to establish equilibrium.

Larger & charged particlesNeed Carrier proteins

3. Osmosis – Diffusion of water across a semi-permeable membrane.a Types of osmosis

1. Isotonic Solution – Equal movements of water into and out of the cell due to equal solute

concentrations.2. Hypertonic – More movement of water out of the cell then in due to more solutes out of the cell.

3. Hypotonic – More movement of water into the cell then out due to more solutes in the cell

Review

How is simple diffusion different from facilitated diffusion?

What would happen to cells that are placed in the following solutions:

isotonic, hypertonic, hypotonic.

E. Active transportRequires energy - ATPGoing against the concentration gradient trying NOT to establish equilibriumEx. Sodium – Potassium Pump

F. Cytosis – Movement of molecules across the cell membrane by forming a vesicle and requiring ATP.1. Two types

a. Exocytosis – Materials leaving the cell.

b. Endocytosis – Materials entering the cell.1. Phagocytosis –

Engulfing large solid particles“cellular eating”

2. Pinocytosis – Engulfing liquids.“cellular drinking”

Movement of Materials Review

Review

►How are facilitated diffusion and active transport similar and how are they different?

►How are phagocytosis, pinocytosis, endocytosis, and exocytosis similar and how are they different?

III. Cytoplasma and Organelles of the cell.A. Cytoplasma – between the cell membrane & nucleu

1. Cytosola. waterb. proteinsc. organic compoundsd. inorganic compounds

2. Organellessmall compartments that do a particular function

B. Types of organelles1. Endoplasmic reticulum (ER) – series of membrane foldsa. Two types Rough (ER) – Hold ribosomes – protein production Smooth (ER) – No ribosomes – Lipid synthesis (hormones),

detoxification.2. Golgi Body – series of membrane folds

Packaging and shipping of proteins

3. Mitochondria – a. Produces energy for the body in the form of ATP.b. Two lipid membranes.

1. Inner – Cristae2. Space – Matrix

c. Own DNA

4. Lysosomes – Contain enzymes to break apart intracellular particles.

5. Peroxisomes – Contains enzymes to detoxify only in the presence of oxygen.

6. Nucleus – “Control center”a. Round.

b. Largest part of the cell.c. Contains genetic material of the cell DNA & RNA.

d. Components1. Nuclear membrane

* bilipid layer* pores for movement

2. Nucleoplasm – similar to cytosol* Nucleoli – composed of RNA and proteins.

* Chromatin-Thin strands of DNA wrapped around proteins balls called histones.

-Contains genes

7. Cytoskeleton – proteins that support the cell, hold organelles & allows the cell to change shape.

Microtubules – hollow structure made of protein sub-unit. (large)

1. Cell division2. Form flagella & cilia3. Cytoskeleton

Microfilament - cellular movement. Filaments(small)

Intermediate – Filaments (between)Ex. Centrioles – helps the cell with cellular division.

8. Cilia 9. Flagella 10. Microvilli

Organelle ReviewOrganelle Review

Organelle ReviewOrganelle Review

Review►What is the function of the following

organelles:golgi ribosome flagellaSER mitochondriaRER cilia

Why is the nucleus referred to as the “control center” of the cell?

IV. Protein SynthesisA. Genetic Code

1. Based on the genetic code.2. Code from your DNA which

contains genes.3. DNA is made up of nucleotides.4. Nucleotides are in groups of

three – codons.

B. First Step in Protein synthesis

1. Transcriptiona. Copying DNA into RNAb. Protects the master copy

2. Three type of RNAa.Messenger RNA – mRNAmRNA Contains the message on how to make the

protein.b. Transfer RNA - tRNA

Transfers the AA to build the protein.- Contains anticodons.

c. Ribosomal RNA – rRNASite of protein production

Composed of large and small subunits.

C. Second Step in Protein Synthesis1. Translation

a. Copying RNA into Proteinsb. Requires all the types of RNA

2. Steps 1. mRNA binds to rRNA 2. The two subunits come together. 3. tRNA with the AA must match up the

ANTICODON to the CODON of the mRNA. 4. Process repeats and peptide bond forms

between the AA until the entire protein is produced.

Transcription, Translation Review

Review

►What is a gene? ►What process do the cell copy DNA

into RNA? Why?

►What role does mRNA play in transcription??

V. Cell DivisionA. Two types

1. Mitosis – Nuclear divisiona. Exact copies of cells are

produced.b. Purpose1. Growth

2. Maintenance3. Repair

c. Diploid to diploid.

d. Stages1. Interphase – cells grows. DNA duplicates.

2. Prophase – Nuclear membrane breaks down. Centrioles move to opposite poles. Chromosomes form.

3. Metaphase – Chromosomes line up at the cells equator.

4. Anaphase – Chromosome separate

5. Telophase – Reverse of prophase.

6. Cytokinesis – Cytoplasm and organelles divide

Mitosis

2. Meiosis – Gamete productiona. Cells are no longer exact

copies.b. Diploid to haploid.c. Purpose

1. Sexual reproduction

1. Interphase2. Prophase I3. Metaphase I

4. Anaphase I5. Telophase I6. Interkineses7. Prophase II8. Metaphase II9. Anaphase II10. Telophase II

VI. Cellular AgingA. Cellular Senescence

1. Irreversible changes within the cell.a. Grayingb. Wrinklesc. Accumulation of body fatd. decreased muscle tonee. Loss of agilityf. Slowing of mental ability.

B. Two theories on aging1. Genetic – RUN OUT OF GAS2. Environmental – FREE RADICALS.