STAAR Year Review

Biomolecules- essential molecules for life. Also seen in lessons throughout the year

Carbohydrates / Lipids / Proteins / Nucleic Acids
Structure /
C, H, O (1:2:1) /
C,H,O /
C,H,O,N /
C,H,O,N,P
Function / Short term energy / Long term energy storage / Enzymes, hormones / DNA or RNA

Cells:

Prokaryotic- a cell without a nucleus. DNA floats freely in the cytoplasm. “Pro no nucleus”

Eukaryotic- a cell with a true nucleus to house DNA “Eu do have a nucleus” Has membrane bound organelles

Organelle / Picture / Function
Nucleus / / DNA storage/ blue print for proteins
Mitochondria / / Cellular respiration- production of ATP
C6H12O6 + 6O2à6CO2 + 6H2O
=36 Adenosine Triphosphate (ATP)
Chloroplast / / Photosynthesis (in plants only) the production of glucose
6CO2 + 6H2O àC6H12O6 + 6O2
Ribosome / / Production of proteins

Eukaryotes-

·  Unicellular or multicellular

·  Membrane bound organelles

·  A Nucleus to store DNA

·  Kingdoms: Plantae, Fungi, Anamalia, Protista

Prokaryotes-

·  Unicellular (one cell)

·  No membrane bound organelles

·  No nucleus

·  Kingdoms: Eubacteria (everyday bacteria) and Archaebacteria (extreme environments)

Cells vs. Viruses

DNA- Storage of genetic information, the “blueprint” for life. How traits are passed from one generation to the next.

·  Monomer of DNA: Nucleotide

·  Components of a nucleotide:

o  Phosphate

o  Sugar

o  Nitrogenous base: Adenine, Thymine, Cytosine, Guanine

Protein Synthesis: Takes DNA’s genetic code and creates proteins that actually make up the body!

Steps of proteins synthesis:

1.  Transcription: DNA à mRNA (messenger) DNA is transcribed into mRNA in the nucleus.

·  mRNA messages are read in codons. It is this message that will be sent to the ribosome.

Example:

DNA TAC GGG TCT GCA GAC ACT

mRNA AUG CCC AGA CGU CUG UGA

2.  Translation: mRNA à protein (also known as a polypeptide)

·  mRNA will travel out of the nucleus through the cell’s cytoplasm to the ribosome.

·  The ribosome reads the mRNA message and has tRNA bring it the amino acids that the message calls for.

·  The tRNA code is not referred to as a codon, it is called an anti-codon.

·  The amino acids brought by tRNA are linked together by the ribosome to create a protein!

Example:

mRNA AUG CCC AGA CGU CUG UGA ßUse this code for your chart!***

tRNA UAC GGG UCU GCA GAC ACU

Amino Acids Met-Pro-Arg-Arg-Leu- Stop

***Do you know how to use BOTH charts?***

The Cell Cycle- only occurs in somatic cells (body cells) not gametes (sex cells). In order to create TWO IDENTICAL DAUGHTER CELLS.

iPMATc – The entire cell cycle

PMAT- Mitosis

o  i – interphase: interphase is the longest phase in the cell cycle. The cell spends most of its life in this stage. There are three phases within this stage.

§  G1- “G= growth of the cell” . More organelles are produced and many proteins are created.

§  S- synthesis of DNA, aka replication of DNA, aka the making of DNA.

§  G2- “G=growth of the cell” and preparation

o  P- Prophase: DNA created in the S phase is condensed into chromosomes.

o  M-Metaphase: The chromosomes created in prophase line up in the middle of the nucleus.

o  A- Anaphase: The chromosomes pull apart to the poles of the nucleus.

o  T- Telophase: The chromosomes reach the poles and the nucleus forms a cleavage furrow (dividing wall down the middle of the nucleus)

o  c-Cytokinesis: The division of the cytoplasm and the entire cell. Now there are 2 identical daughter cells.

S phase of DNA- is the synthesis or REPLICATION of DNA

Steps of DNA Replication:

Meiosis- the creation of gametes (sperm and egg) which are haploid cells (half the number of chromosomes),in order for organisms to reproduce. The number of chromosomes is halved. Each daughter cell is different!

Steps:

·  Meiosis 1- P1, M1, A1, T1 is much like mitosis. However, meiosis has crossing over during prophase 1 of meiosis 1.

o  Crossing over- homologous chromosomes (same chromosome from mom and dad) switch genetic material in order that the offspring has varying traits from the mother and father.

·  Meiosis 2- P2, M2, A2, T2 is much like mitosis again however the number of chromosomes are halved in meiosis 2 to create haploid cells.

Mendelian Genetics-

Genetics- the study of inheritance.

·  Trait- a characteristic such as EX: eye color, hair color, blood type

·  Allele- the different genes for a trait. EX: Blue eyes or brown eyes. Blonde hair or brown hair. A or B blood type

·  Frequencey- how often something occurs.

·  Genotype- What the genes say

·  Phenotype- What the physical appearance is.

·  Dominant- a trait that will ALWAYS show up if present

·  Recessive- a trait that will only show up if there is not a dominant trait present.

·  Monohybrid- a cross concerning only ONE trait

·  Dihybrid- a cross concerning TWO traits

·  Heterozygous- a genotype in which there is a dominant and recessive trait EX: Bb

·  Homozygous Dominant- a genotype in which you receive a dominant trait from both parents. Ex: BB

·  Homozygous Recessive- a genotype in which you receive a recessive trait from both parents. Ex: bb

Monohybrid Problem-

Set up the punnett square for each of the crosses listed below. The trait being studied is round seeds (dominant) and wrinkled seeds (recessive)

Rr x rr

Genotype ratio- RR:Rr:rr

Phenotype ratio- Round:Wrinkled ( Dominant appearance: Recessive appearance)

Dihybrid Problem- You will use this method when crossing any two traits.

A pea plant that is heterozygous for round, yellow seeds is self fertilized, what are the phenotypic ratios of the resulting offspring?

Step 1: Determine the parental genotypes from the text above, the word "heteroyzous" is the most important clue, and you would also need to understand that self fertilized means you just cross it with itself.

RrYyxRrYy

Step 2: Determine the gametes. This might feel a little like the FOIL method you learned in math class. Combine the R's and Ys of each parent to represent sperm and egg. Do this for both parents

Gametes: RY, Ry, rY, ry (parent 1) andRY, Ry, rY, ry(parent 2)

Step 3: Set up a large 4x4 Punnet square, place one gamete set from the parent on the top, and the other on the side

Step 4: Write the genotypes of the offspring in each box and determine how many of each phenotype you have. In this case, you will have 9 round, yellow; 3 round, green; 3 wrinkled, yellow; and 1 wrinkled green.