Biology 1107 2

Is energy added or released when breaking bonds?

Is energy added or released when forming bonds?

Released

What is an isotope

atoms of the same element that have different numbers of NEUTRONS

What happens to an atom when is loses/ gains an electron?

When it loses it becomes a positively charged ion and when it gains it becomes a negatively charged ion

What is cohesion?

Water molecules cling together.

What is adhesion?

Water molecules cling to surfaces

What is the polar scale?

CHPS

What are isomers?

Same chemical formula but different structures.

What are protein characteristics?

Function: Provide support/structure; acts as catalysts for chemical reactions
Subunits: amino acids

Characteristics of amino acids?

Makeup: amino group, R group, carboxyl group
Bonds: Held together by polypeptide bonds

How does a peptide bond form?

The OH from one amino acid's carboxyl group and the H from the other's amino group combine to form H20. H20 is released and C-N bonds.

Nucleic acid characteristics?

Function: Transmit and encode genetic info
Makeup: Nucleotides

Characteristics of nucleotides?

Makeup: A five carbon sugar with a base attached to 1' carbon, OH/H attached to 2' carbon, OH attached to 3' carbon, phosphate group attached to 5' carbon.

What is the difference between ribose and deoxyribose?

Ribose has an OH group at the 2' carbon while deoxyribose has an H at the 2' carbon.

What are the pyrimidine bases?

cytosine, thymine, and uracil

What are the purine bases?

guanine and adenine

What are the bonds between nucleotides and how do nucleotides join?

Type: phosphodiester bonds
How: The phosphate group of one is joined to the sugar of the other

What are the characteristics of carbohydrates?

Function: Structure and energy
Makeup: Monosaccharides

What direction is the template strand in?

3'-5'

What direction is the RNA transcript formed in?

5'-3'

Which enzyme is responsible for the start of transcription?

RNA polymerase

Where is the enhancer and promoter present?

In DNA and the template strand

Where are exons present?

In the primary RNA transcript and mRNA

Where are introns present?

In only the primary RNA transcript

Where is the polyA tail present?

mRNA

What is splicing?

Removing introns from the primary RNA transcript, leaving only the exons.

What properties do the head of the phospholipid and the tail of the phospholipid have?

The head is hydrophilic while the tail is hydrophobic

What shape do phospholipids with bulky heads form?

A micelle

What shape do phospholipids with small head form?

A bilayer

What shape do micelles form in a test tube?

What shape do micelles form in a test tube?

How do small non polar molecules pass through the membrane?

Easily because the bilayer has a non polar inside

How do small uncharged polar molecules pass through the membrane?

Easily depending on the molecule

How do large uncharged polar molecules pass through the membrane?

Not very well

How do charged ions pass through the membrane?

They dont

How would glucose pass through a bilayer?

Through facilitated diffusion because it is large and polar so it needs help.

How would K+ pass through the bilayer?

Through active transport because it needs energy in order to move through.

What is passive transport?

When a molecule easily passes through the membrane because the concentration gradient is in its favor. Molecules easily move towards areas of low concentration bc it wants to be isotonic.

What is a phototroph?

An organism that obtains energy from the sun

What is a chemotroph?

An organism that obtains energy from chemical compounds

What is an autotroph?

It converts CO2 to glucose to make its own carbon

What is a heterotroph?

Cannot make their own energy sources therefore they have to ingest carbon

What is the first law of thermodynamics?

Energy cannot be created or destroyed

What is the second law of thermodynamics?

When energy changes form, the total amount of energy remains constant, however, the amount of energy available to do work decreases.

What is Gibbs free energy?

The energy available to do work

what does a negative delta G indicate

An exergonic reaction

What does a positive delta G indicate?

An endergonic reaction

What kind of reaction are catabolic reactions

exergonic

What kind of reactions are anabolic?

endergonic

How do you calculate delta G?

Products-reactants. (leave negative sign to show exergonic)

How do you calculate activation energy?`

Transition state- reactants

What happens during the transition state?

Old bonds are breaking and new bonds are forming

What do enzymes do to speed up a reaction?

They lower activation energy

What do activators do?

Increase the activity of the enzyme

What do competitive inhibitors do?

They compete with the substrate. They bind to the active site before the substrate can.

What do allosteric inhibitors do?

They bind to a site that's not the active site. They slow the reaction down to a stop by changing the enzyme's shape.

What is the cellular respiration equation?

glucose+oxygen=CO2+H2O+ATP

Where does glycolysis occur?

The cytoplasm

What is substrate level phosphorylation?

When ADP is converted into ATP by the addition of a phosphate

Where does substrate level phosphorylation occur?

glycolysis and the citric acid cycle

What is oxidative phosphorylation?

When electron carriers donate electrons to produce ATP.

How is the majority of energy produced in cellular respiration?

Through oxidative phosphorylation

What is oxidized in the cellular respiration equation?

glucose to become CO2

What is reduced in the cellular respiration equation?

Oxygen to become water

What are the oxidized forms of the electron carriers?

NAD+, FAD

What are the reduced forms of the electron carriers?

NADH, FADH2

What is the starting/ending molecule of glycolysis?

Start: glucose
End: pyruvate

Is glycolysis aerobic or anaerobic?

anaerobic

What are the reactants of glycolysis that hold potential energy?

glucose and ATP

What are thee products of glycolysis that hold potential energy?

pyruvate, ATP, NADH

In whole, how many ATP are produced from glycolysis?

4, but 2 are consumed during the reaction

What is pyruvate oxidized to during acetyl-CoA synthesis?

CO2 and acetyl

How many pyruvates are created for each glucose?

2

Which electron carrier is reduced during acetyl-CoA synthesis?

NAD+ is reduced to NADH

Which molecule is broken down initially in the citric acid cycle?

acetyl-CoA

Where does the energy transfer to when released from the breakdown of acetyl-CoA?

to ATP from substrate level phosphorylation and to NADH and FADH2

Which two processes take place in the mitochondrial matrix?

acetyl-CoA synthesis and the citric acid cycle

Where does the CO2 humans exhale come from?

Pyruvate oxidation(acetyl-CoA synthesis) and the citric acid cycle

Where is the electron transport chain located?

the inner mitochondrial membrane

What enters the electron transport chain via complex I?

NADH

What enters the electron transport chain via complex II?

FADH2

How is ATP synthesis possible on the electron transport chain?

The movement of protons through protein channels is coupled with the synthesis of ATP

What is F0 of ATP synthase?

It forms the channel that allows proteins to flow in the inner mitochondrial membrane

Does F0 or F1 rotate?

F0

How does the rotation of F0 promote the synthesis of ATP?

F0 takes protons in, causing it to rotate. This rotation converts the energy into kinetic (mechanical) energy which is then converted into chemical energy by joining ADP and P

What is the oxidizing agent in cellular respiration?

Oxygen

What is the reducing agent in cellular respiration?

glucose

How is pyruvate broken down in the absence of oxygen?

fermentation

What provides ATP for muscle contraction?

glycogen

Where is glycogen stored?

in the muscle and liver cells

Where is glycogen stored to be used for the whole body?

the liver

What is produced from B-oxidation

NADH and FADH2

What would occur when pyruvate is low

B-oxidation

What happens if the cell has high levels of NAD+

cellular respiration is stimulated

What happens if the cell has high levels of NADH

cellular respiration is slowed down

What creates the signaling molecule?

The signaling cell

What is endocrine signaling

Signaling through the bloodstream

What is paracrine signaling?

Cells nearby each other send signals

What is autocrine signaling?

Cell produces signaling molecule and also has the receptor

What is contact dependent signaling?

Signaling occurs because of direct contact between cells

What is a ligand?

the signaling molecule