Cellular membranes are fluid mosaics of what?

Lipids and proteins

What are the must abundant lipids in the plasma membrane?

Phospholipids

What does amphipathic mean?

having both a hydrophobic and hydrophillic region.

What does a phospholipid bilayer do?

creates a stable boundary between 2 aqueous compartments

Describe a phospholipid

hydrophilic head and hydrophobic tail

What role does cholesterol play on the movement of phospholipids?

It lowers it movement

What are the 2 types of membrane proteins?

Peripheral(outside the cell membrane) and integral(inside the cell membrane)

What is a glycoprotein?

are proteins and carbs covalently bonded. They help with a variety of functions.

What is a gylcolipid?

are lipids and carbs covalently bonded. Help maintain the stability of the cell and facilitate cellular recognition.

What controls how the cell exchanges materials with its surroundings?

Plasma membrane

What permeability are plasma membranes?

Selectively permeable

What are transport proteins?

they allow passage of hydrophilic substances across the membrane

What do channel proteins called aquaporins do?

facilitate the passage of water

What does a carrier protein do?

they bind to molecules and change shape to shuttle them across the membrane

Know the types of membrane transport.

Active vs passive

What is osmosis?

the diffusion of water across a selectively permeable membrane. Water diffuses from low to high concentrations.

What is isotonic, hypertonic, and hypotonic

isotonic - no net water movement

hypertonic - water leaves the cell

hypotonic - water comes into the cell

What is tonicity?

the ability of a surrounding solution to cause a cell to gain or lose water

What is osmoregulation?

the control of solute concentrations and water balance

Active transport requires energy from what?

ATP

The sodium postassium pump is a type of what transport?

Active transport

What is exocytosis?

transport vesicles migrate to the membrane, fuse with it, and release their contents outside the cell

What is endocytosis?

the cell takes in macromolecules by forming vesicles from the plasma membrane

What are the 3 types of endocytosis?

1. Phagocytosis (“cellular eating”)
2. Pinocytosis (“cellular drinking”) Receptor-mediated

3.endocytosis

What is metabolism?

the chemical process in the cells of living organisms that allow them to convert food and drink into energy and waste

What is a catabolic pathway?

release energy by breaking down complex molecules into simpler compounds

What is an anabolic pathway?

consume energy to build complex molecules from simpler ones

What are some of the forms of energy?

Kinetic, heat(thermal), potential, and chemical

What is thermodynamics?

The study of energy transformation

What is the first law of thermodynamics?

Energy can be transferred and transformed, but it cannot be created or destroyed

What is the second law of thermodynamics?

Every energy transfer or transformation increases the entropy (disorder) of the universe

What is entrophy?

The measure of disorder

What does the free energy of reactions tell us?

If the reaction is spontaneous

What does spontaneous mean?

energetically favorable

What is the equation for Gibbs free energy?

energy that can do work when temperature and pressure are uniform

What is a exogenic reaction?

proceeds with a net release of free energy and is spontaneous

What is endogenic reaction?

absorbs free energy from its surroundings and is nonspontaneous

When a reaction equals equilibrium will they do work?

No

What are the 3 main kinds of work that a cell does?

Chemical, transport, mechanical

What is ATP made of?

3 phosphate groups, adenine, and ribose

How does ATP regenerate?

The ATP cycle is a revolving door through which energy passes during its transfer from catabolic to anabolic pathways. (Goes from ATP to ADP)

What is a catalyst?

chemical agent that speeds up a reaction without being consumed by the reaction

What is an enzyme?

A catalytic protein that lowers activation energy

What is the reactant that an enzyme act on?

substrate

How is an enzyme substrate complex formed?

when an enzyme binds to its substrate

What are cofactors?

they are non-protein enzyme helpers

What is an organic cofactor called?

coenzyme

What are competitive inhibitors?

they bind to the active site of an enzyme, competing with the substrate

What are noncompetitive inhibitors?

bind to another part of an enzyme, causing the enzyme to change shape and making the active site less effective

What is allosteric regulation?

occurs when a regulatory molecule binds to a protein at one site and affects the protein’s function at another site

What is cooperativity?

a form of allosteric regulation that can amplify enzyme activity

What are some functions of membrane proteins?

cell-cell recognition, intercellular joining, enzymatic activity, and transport

Where are carbs found in the fluid mosiac model of the plasma membrane?

On the outside surface of the membrane.

Where is cholesterol found in the fluid mosiac model of the plasma membrane?

The interior of the membrane

Describe passive transport.

permits the solute to move in either direction, but the net movement of solute molecules occurs down the concentration gradient of the molecule.

Does facilitated diffusion need energy (ATP)?

No

What do electrogenic pumps do?

Create a voltage difference across the membrane

Know the fluid mosaic model.

Simple vs facilitated diffusion.

Simple moves small, non polar molecules

Know the gibbs free energy equation and what they mean.

Does the sign and magnitude of the ΔG of a reaction tell us about the speed of the reaction?

No, it has nothing to do with the speed of the reaction

The majority of spontaneous reactions ________ the entropy of the system.

increase

What does photosynthesis do?

converts the energy of sunlight into chemical energy stored in sugars.

What are the differences between autotrophs and heterotrophs

autotrophs produce their own food form co2 while heterotrophs are unable to make their own food and live on compounds produced by others.

Where does photosynthesis occur?

In the chloroplast organelles containing thylakoids

What is the photosynthesis equation

Why is photosynthesis know as a redox reaction?

Because H2O is oxidized and CO2 is reduced

Explain the light reaction that happens in photosynthesis

the thylakoid membranes split water, releasing O2, producing ATP, and forming NADPH.

Explain the dark reaction (calvin cycle) that happens in photosynthesis

in the stroma forms sugar from CO2, using ATP for energy and NADPH for reducing power.

Photosystem II contains what chlorophyll a molecule

P680

Photosystem I contains what chlorophyll a molecule

P700

What comes first photosystem I or II

Photosystem II

What are the 3 steps of the calvin cycle?

1. carbon fixation

2. Reduction

3. Regeneration of CO2 acceptor

How does CO2 enter the plant

Through the stoma

What is the role of NADP⁺ in photosynthesis?

It forms NADPH to be used in the calvin cycle

What does pigments do in photosynthesis

Capture light energy

Where do the electrons entering photosystem II come from?

water

Know the model for photosynthesis

Both mitochondria and chloroplasts

use chemiosmosis to produce atp

What is the role of NADP⁺ in photosynthesis?

It is reduced then carries electrons to the calvin cycle

Which of the following occurs during the Calvin cycle?

ATP is hydrolyzed and NADPH is reduced and CO2 is reduced

What is rubisco?

the enzyme in plants that captures CO₂ to begin the Calvin cycle

What are the correct order of the three phases of Calvin cycle.

Carbon fixation → Glyceraldehyde-3-Phosphate synthesis → Ribulose BisPhosphate regeneration

What is the cell signaling pathway

1. Signal reception

2. Signal transduction

3. Cellular response

What are the 3 major types of cell recptors?

G protein coupled receptors, Receptor tyrosine kinase, and Ligand gated ion channels

Compare fermentation to cellular respiration?

Fermentation is a process that results in the partial degradation of glucose without the use of oxygen O2. The process of cellular respiration is a more complete breakdown of glucose.

What is oxidation?

The total or partial loss of electrons

What is reduction?

The total or partial addition of electrons

What are the 3 stages of aerobic respiration?

1. glycosis

2. pyruvate oxidation and the citric acid cycle

3. oxidative phosphorylation

Describe the first step of glycosis.

glucose is broken down into 2 pyruvate molecules and s net ATP/ 2 NADH.

Describe the citric acid cycle.

pyruvate enters the mitochondrion and is oxidized to acetyl CoA.

-ATP, CO2, NADH, and FADH2 is outputted.

Describe the electron transport chain?

NADH and FADH2 transfer electrons to the electron transport chain. Electrons move down the chain, losing energy in several energy-releasing steps. Finally, electrons are passed to O2, reducing it to H2O.

About how many ATP are produced after the electron transport chain?

32

What are the 2 common types of fermentation

alcohol fermentation and lactic acid fermentation.

Most of the ATP produced in cellular respiration comes from which of the following processes?

Oxidative phosphorylation

Where do the reactions of glycolysis occur in a eukaryotic cell?

The cytosol

What are the products of glycosis?

pyruvate, ATP and NADH

Arrange the following stages of cellular respiration from the lowest to the highest on the basis of the total amount of ATP produced per molecule of glucose.

Pyruvic acid oxidation, Krebs cycle, Glycolysis, Oxidative phosphorylation

Which of the following molecules in the process of glycolysis possesses the most chemical energy?

Fructose-1,6-bisphosphate