Science UIL

Photosynthesis equation?

6H​2O + 6CO​2 = C₆H₁​20₆ + 6H​2O

Calvin cycle steps?

1. Carbon fixation (CO​2 to 3-PGA)

2. ATP & NADPH change 3-PGA to GP3; ATP and NADPH become ADP and NADP+; GP3 = ½ molecule of glucose

3. RuBP regenerated, which fixates carbon

Respiration equation?

C₆H₁​2O₆ + 6O​2 = 6H​2O + 6CO​2 + ATP

What do the smooth and rough ER do?

Smooth - synthesizes and packages lipids

Rough - synthesizes and packages proteins

What does the Golgi body do?

packages and sends proteins throughout the cell

What do the peroxisomes do?

collects and breaks down toxins

What do the centrioles do?

organizes chromosomes during division

What does a lysosome do?

breaks down large pieces into smaller ones

What does the cytoskeleton do?

made of filaments and tubules, adds structure to cell

What is the cell membrane made of?

Lipid bilayer; hydrophobic heads outside, hydrophilic tails inside

What do receptor and transport proteins do?

Receptor proteins relay messages, transport proteins move things in and out

Which is faster: carrier proteins or channel proteins in the cell membrane?

Channel proteins

What does cholesterol do in the cell membrane?

Cholesterol maintains fluidity by protecting against temperature fluctuations

What do the cell membrane's aquaporins do?

Allow water to diffuse in

What is diffusion?

The natural spreading of molecules from high to low concentrations

What is passive transport?

Molecules that are charged/polar need protection from the hydrophobic heads, so they travel through protein channels

What is facilitated diffusion?

Molecules that are charged/polar need protection from the hydrophobic heads, so they travel through protein channels

What is active transport?

Movement of molecules against the gradient through protein pumps, using ATP energy

What is the element ratio in carbohydrates?

C:H2O

What is the element ratio in proteins?

CHON, variable

What is the element ratio in lipids?

C/1H​2O

What is the element ratio in nucleic acids?

CHONP, variable

What is the monomer of carbohydrates?

Monosaccharides

What is the monomer of proteins?

Amino acids

What is the monomer of lipids?

Glycerol; fatty acids

What is the monomer of nucleic acids?

Nucleotides; ribose (RNA)/deoxyribose (DNA);

What is the shape/structure of a carbohydrate?

Ring shape

What is the shape/structure of a protein?

Variable

What is the shape/structure of a triglyceride?

Chain shape: glycerol backbone with three fatty acids/carboxylic acids

What is the shape/structure of a phospholipid?

'Head-and-tail' shape: Hydrophilic head of a phosphate attached to a glycerol; hydrophobic tails of two saturated fatty acids attached to the glycerol, one of which turns into a "kinked" unsaturated fatty acid

What is the shape/structure of a nucleic acid?

RNA: single helix; DNA: double helix

What is the purpose of a carbohydrate?

for quick energy (glucose), energy storage (starch, fructose), building molecules (ribose), structure (chitin)

What is the purpose of a protein?

Antibodies, enzymes, messengers, structure, almost all functions

What is the purpose of a lipid?

Energy storage; warmth; cell membrane

What is the purpose of a nucleic acid?

Storage of genetic information (DNA); transporting information from DNA to ribosome (RNA)

Name and describe the cell cycle phases.

G1 (cell contents (not chromosomes) duplicated)

S (chromosomes duplicated)

G2 (cell grows; chromosomes double-checked)

Mitosis

Cytokinesis

How is the cell cycle regulated?

By cyclins and CDK

What are the steps for DNA replication?

Gyrase relaxes the DNA

Helicase unwinds the DNA

DNA polymerase takes free-floating nucleotides and attaches them to the now-exposed base pair on the mother strand

Continues until two DNA strands are formed

What is the genome?

All the DNA in the whole cell.

What are the phases of mitosis?

Interphase (DNA is copied)

Prophase (Early: Chromosomes pair + condense, mitotic spindle forms, nucleolus dissolves

Late/Prometaphase: Mitotic spindle captures chromosomes, nucleus dissolves)

Metaphase (Chro's line up at the metaphase plate) Anaphase (Chromosomes separate, driven by motor proteins)

What is the mitotic spindle made out of?

2 asters (the T) and kinetochore tubules, which connect at the chromosome's centromere

Where does glycolysis occur?

In the cytoplasm.

What does glycolysis do?

Breaks down glycolysis into pyruvate and two molecules of ATP

What is metabolism?

The chemical processes that occur within a living organism in order to maintain life.

What is the purpose of cellular respiration?

To break down carbohydrates into ATP molecules.

What are the three stages of cellular respiration?

1. Glycolysis

2. Krebs cycle

3. Electron transport chain

What are the steps of photosynthesis?

1. Light hits the thylakoid membrane, splitting H2O into O2 and releasing electrons

2. The electrons travel down to special enzymes and generate ATP and NADPH from NADP and ADP

3. Calvin cycle

What do enzymes do?

Catalyze reactions

What are enzymes made out of?

Proteins

What is the 'active site'?

The area of an enzyme where the reaction occurs.

How many molecules can one enzyme react with?

One; enzymes are specific

Do enzymes change shape to fit the molecule?

Yes

What do you call the molecule that goes into an enzyme?

The substrate

What is a competitive inhibitor?

A substrate that binds to the active site of an enzyme and prevents it from working

What is a non-competitive inhibitor?

A substrate that binds to a different site on the enzyme and changes its shape

What does tRNA do?

Transfer amino acids to the ribosome

What is a codon?

A set of 3 nucleotides on DNA that code for one amino acid

What is transcription?

The transfer of DNA to an mRNA strand

What is translation?

Changing the information on an mRNA strand to an amino acid chain via a ribosome

Where does mRNA leave the nucleus?

Through nuclear pores

What is an anticodon?

A set of 3 nucleotides that correspond to one amino acid

How do histones affect gene regulation?

They control what genes can be accessed by coiling around DNA.

What is gene regulation?

Regulating how traits are expressed through a variety of mechanisms.

What are 'enhancer' sites?

Sites on DNA that increase the rate of transcription of a certain gene.

What are 'silencer' sites?

Factors that slow the rate of transcription of a gene.

What are some methods of gene regulation?

Regulators on the rate of transcription, the processing of RNA molecules, the stability of RNA molecules, and the rate of translation.

What are introns?

Parts of DNA that do not code for an amino acid

What do introns do?

Regulate gene expression

Missense mutation

Replaces one base pair and produces a different amino acids

Nonsense mutation

Replaces one base pair and produces a premature stop codon

Insertion mutation

An extra base pair inserted where it is not called for

Deletion mutation

Deletion of a base pair

Duplication mutation

A piece of DNA that is copied once or multiple time

Frameshift mutation

A shift in the DNA reading frame; i.e.

CGA TAG CAG ACG becomes

GAT AGC AGA CG

Mendel's 1st law (Segregation)

The two members of a gene pair (alleles) segregate from each other in the formation of gametes. Half the gametes carry one allele, and the other half carry the other allele.

Mendel's 2nd law (Independent assortment)

Genes for different traits assort independently of one another in the formation of gametes.

What does a "3:1" phenotypic ratio mean?

Three of four organisms will have one phenotype, and one of four will have another phenotype when two heterozygous organisms are crossed.

What is the F1 generation?

The first generation out from the parent generation.

What is the F2 generation?

The generation that results when the F1 generation is all bred together.

Which does NOT follow Mendel's laws: genotypes or phenotypes?

Phenotypes

What ratio do lethal genotypes change; genotype or phenotype?

Phenotype; because we don't see the phenotype as the organism dies quickly, we assume the phenotypes are all dominant