Mid Year Review What you should recall!. What is biology? The study of life! ▫Living ▫Non-Living ▫Dead All living things ▫Have an orderly structure ▫Produce.

Mid Year ReviewWhat you should recall!

What is biology?

•The study of life!▫Living▫Non-Living▫Dead

•All living things ▫Have an orderly structure▫Produce offspring▫Grow and develop▫Adjust to changes in the environment

Terms to Know!

•Independent Variable (IV)▫The condition that is changed

•Dependent Variable (DV)▫Changes based on the independent variable

•Constants▫Components of the experiment that remain

the same•Controls

▫Keep your experiment fair (ie. Time, location)

Practice #1Identify the:- IV, DV, constants, control- Write a title and hypothesis for the scenario

A shopping mall wanted to determine whether the more expensive “Tough Stuff” floor wax was better then the cheaper “Steel Seal” floor wax at protecting its floor tiles against scratches. One liter of each brand of floor wax was applied to each of 5 test sections of the main hall of the mall. The test sections were all the same size and were covered with the same kind of tiles. Five (5) other test sections received no wax. After 3 weeks, the number of scratches in each of the test sections was counted.

•IV: Tough Stuff or Steel Seal Cleaner applied to floor

•DV: Number of scratches on the floor•Constants: test section, type of tiles•Control: 5 test sections where no cleaner

was applied•Title: The Effect of Floor Cleaner on the

Number of Scratches•Hypothesis: If tough stuff floor cleaner is

applied, there will be fewer scratches on the floor.

Intro to Biochemistry!

•Terms to Know▫Neutrons▫Electrons▫Protons▫Nucleus▫Atomic mass▫Atomic Weight▫Compound▫Isotopes

•# of protons = # of electrons

Oxygen

8

O16

Phosphorus

15

P31

Calcium

20

Ca40

Symbol:

# of Protons:

# of Neutrons:

# of Electrons:

Symbol:

# of Protons:

# of Neutrons:

# of Electrons:

Symbol:

# of Protons:

# of Neutrons:

# of Electrons:

Isotopes

•Atoms that have the same number of protons but different amounts of neutrons

•What happens if the number of protons change in the element? Why?

Biochemistry!•Terms to know

▫Monomers▫Carbohydrates (monosaccharide)▫Lipids (fatty acids)▫Nucleic Acids (nucleotides)▫Proteins (amino acids)▫Monosaccharide▫Polysaccharide▫Disaccharide

glucose

glucose

glucose

glucose

glucose

glucose

glucose

Proteins (Polypeptides)•Monomer – Amino acids (20 different

kinds of amino acids) bonded together by peptide bonds.

aa 1

aa 2

aa3aa 4

aa 5

Amino Acids

Peptide Bonds

Link together in different orders and lengths to create thousands of different proteins. THE SHAPE OF THE PROTEIN DETERMINES THE FUNCTION.

What are Enzymes?

•Enzymes are proteins.•Act as catalysts to speed up a chemical

reaction between reactants (substrates) that form new products.

2H2 + O2 2H2O reactants products (substrates)

How do Enzymes Work?

•All chemical reactions need energy to begin. This is called ACTIVATION ENERGY. ▫Activation energy = the energy needed to

start a reaction.

•After undergoing a reaction in the enzyme-substrate complex, the substrate has changed and is now a product.

1. Enzymes work best at optimum temperatures and pH.

▫ extreme temperature and pH can change the shape of the enzyme, affecting the binding “active” site.

▫ Conditions too far away from the ideal may cause the enzyme to denature and not work.

▫ Enzymes in our body work best at 37C (98.6F) and at pH between 6.5 and 7.5.

Acid = 0-6.9Neutral = 7Base = 7.1 – 14

Cells!• Terms to know

▫ Microscopes▫ Passive Transport▫ Active Transport▫ Osmosis▫ Hypotonic▫ Hypertonic▫ Isotonic▫ Positive Feedback▫ Negative Feedback

Photosynthesis

•Factors that affect Photosynthesis▫Light Intensity▫CO2 concentration▫Temperature

Anaerobic Respiration

•Does NOT use Oxygen

•Uses ONLY food (glucose) to make ATP

•makes very little ATP

Aerobic (Cellular) RespirationUses O2 and

food (glucose) to make ATP

Makes LOTS of ATP

Occurs in the MITOCHONDRI

A

All organisms except some

fungi and bacteria

Produces H2O and CO2

DNA Structure

DNA Structure•Double Helix •Twisted ladder structure •Sides have alternating

phosphate sugar groups•“Rungs of a DNA ladder”

“Chargoff’s rule”

A = T & C = G

(Complementary Base Paring)

DNA ReplicationProvide the complement to the following original DNA strand:A T C G A G G C C A A T T

DNA vs RNA

DNA RNA

• Double Helix • Twisted ladder structure • Sides have alternating

phosphate sugar groups• “Rungs of a DNA ladder”

• RNA differs in three main ways:▫ Single stranded▫ Ribose sugar▫ Thymine (T) is replaced

with Uracil (U) Still pairs with Adenine

(A)

• Remember: The Central Dogma (DNA to RNA; RNA to Proteins)

Transcription

•DNA to RNA▫Big Picture: to make proteins (protein

synthesis)▫mRNA (messenger) brings the message▫rRNA (ribosomal) uses instructions from

mRNA to assemble the amino acid▫tRNA (transfer) delivers the amino acids to

the ribosome to be assembled into a protein.

Translation• Takes place on the

ribosome• tRNA brings the amino

acid to the ribosome• Each tRNA molecule only

attaches to only one type of amino acid.

Mutations•Any change in the DNA sequence•Cancer is a mutation!

▫ie. Skin, lung, brain, and pancreatic cancer

Recombinant Bacteria1. Remove bacterial DNA

(plasmid).

2. Cut the Bacterial DNA with “restriction enzymes”.

3. Cut the DNA from another organism with “restriction enzymes”.

4. Combine the cut pieces of DNA together with another enzyme and insert them into bacteria.

5. Reproduce the recombinant bacteria.

6. The foreign genes will be expressed in the bacteria.

Human Genome Project/ Ethics•Human Genome Project- Aims of the project:

- to identify the approximate 100,000 genes in the human DNA.- determine the sequences of the 3 billion bases that make up human DNA.

- store this information in databases.- develop tools for data analysis.- address the ethical, legal, and social issues that arise from genome research.

Mid Semester Review Closing

• Pleases be sure to study all notes posted on web page and in your handouts!

• Complete review packet for Test Grade!• Due on Friday!• Email me, stay after, or come before if there are

any questions

• Inheritance Genetics was covered in previous review packet!