Cells Test

Which side of the membrane has a negative charge at the start of an action potential?

The inside

What is the resting membrane potential?

-70 mV

What is the membrane potential value at which the voltage-gated channels begin to open?

-55 mV

What is the membrane potential value at which the Na⁺ inactivation gate closes and the K⁺ channel is at full capacity?

40 mV

Axon

The long “arms” of a neuron through which electric currents send information to other cells

What are the axon’s insulators called?

Schwann cells

Synapse

A connection between two neurons, often on a dendrite

Dendrite

“Ports” where neurons receive information from the axons of other cells

What is the Carbon-counting rotation in the Calvin Cycle?

6×1 (enters) + 6×5 → 12×3 → 12×3 → 1×6 (exits) + 10×3 → 6×5

What are the steps of photorespiration?

6x RuBP (5C) + 6x O₂ → 6x PGA (3C) + 6x 2PG (2 C) →(ATP input, CO₂ waste)→ 6x G3P (3C) + 3x G3P (3C)→9x G3P (3C) →(ATP input, Carbons from aerobic respiration)→ 6x RuBP (5C)

What is the second set of molecules in the photorespiration cycle?

6x PGA (3C) and 6× 2PG (2C)

How many G3P molecules does the photorespiration cycle use?

9

How does the photorespiration cycle turn 9 G3Ps into 6 RuBPs?

With a lot of ATP input and C from cellular respiration

What are the 2 places where cellular respiration requires ATP input?

1. Turning 6x 2PG into 3x G3P

2. Turning 9x G3P into 6x RuBP

What is the result of the oxidation of NADH?

NADH → NAD⁺ + 2H⁺

What is the result of the oxidation of FADH₂?

FADH₂ → FAD⁺ + 2H⁺

What are the two electron carriers that are used inside the membrane in oxidative phosphorylation?

Q and Cyt c

How many proton pumps are there in oxidative phosphorylation?

3

Where do electrons used to power the protons in oxidative phosphorylation “end up?”

Getting pulled by O into a bond with O and 2x H⁺ to create H₂O

Where does the CAC happen?

The mitochondrial matrix, inside both membranes

Where does oxidative phosphorylation happen?

The inner mitochondrial membrane (the squiggly one)

What is the Carbon-grabbing enzyme used in C₄ and CAM photosynthesis?

PEP Carboxylase

Into what molecule are carbons fixed in C₄ and CAM photosynthesis?

Oxaloacetate, which then becomes malate

What does ATP stand for?

Adenosine Triphosphate

What are 3 reasons compartmentalization is helpful?

1. Specialization = efficiency

2. Harnessing localized energy

3. Controlling functions’ environments

Which ion moves first in action potentials? Which way does it go?

Na⁺; moves into the cell

Is the cell wall a membrane?

No

Which membrane do action potentials take place in?

Plasma membrane

What are the three steps of the Calvin Cycle?

Fixation, reduction, and regeneration

What is the unit used to measure the wavelength of light waves?

Nanometers, nm

What is the matrix of the mitochondria

The space inside the inner membrane; the citric acid cycle happens here

What are the inputs and outputs of the citric acid cycle?

Inputs: Acetyl CoA

Outputs: CO₂, NADH, and FADH₂

Catabolic

Produces energy

Anabolic

Requires energy

What are the products of cellular respiration?

ATP, H₂O, and CO₂

Where do each of the electron carriers give electrons to in oxidative phosphorylation? How many do they give?

NADH gives 2 electrons to proton pump I, and FADH₂ gives two to Q

What is chlorophyll?

Umbrella term for P680 and P700, the dye molecules that are excited by light waves

What is “complex II” in cellular respiration?

A protein that feeds electrons into the Q carrier

What is the order in which electrons pass through the complexes of cellular respiration?

Proton Pump I —> Q (more fed in via complex II) —> Proton Pump III —> Proton Pump IV —> Exit by reducing O₂ into H₂O