Exam Study Guide Template

BIO 201 · Cell Biology Fall 2026 · Midterm 1

MidtermStudy Guide

Cells, membranes, energy and division — Lectures 4–9 on 12 pages.

Built from _PPTX_BIO 201 Lectures 4–9 _TXT_my-notes-final.txt

5topics
1 cheat
sheet

_01_Cell structure & organelles

_02_Membrane & transport

_03_Cellular respiration

_04_Photosynthesis

_05_Cell cycle & mitosis

21practice
questions

7labelled
diagrams

1answer key
+ checklist

Exam dayThu, Oct 23 · 10:00Life Sciences 140

BIO 201 · Midterm Study Guide Start here

What’s

inside ↓

01 Cell structure & organellesLecture 4 · organelles, endomembrane system p.3

02 Plasma membrane & transportLecture 5 · fluid mosaic, diffusion, osmosis p.4

03 Cellular respirationLectures 6–7 · glycolysis to ATP synthase p.5

04 PhotosynthesisLecture 8 · light reactions, Calvin cycle p.7

05 Cell cycle & mitosisLecture 9 · interphase, PMAT, checkpoints p.8

★ One-page cheat sheetEverything above, on one page p.9

? Practice quiz16 multiple choice, 1 diagram, 4 short answer p.10

✓ Answer key & exam-day checklistMark it yourself, then fix the gaps p.12

Exam at a glance

Thu, October 23
10:00–11:50 AM

Life Sciences Building, room 140 · bring a #2 pencil and your student ID · no calculators

40multiple choice · 60%

1diagram to label · 10%

4short answer · 30%

Where the marks are

15

20

25

20

20

Cell structure 15% Respiration 25% Membrane 20% Photosynthesis 20% Cell cycle 20%

Prof. Okafor said in Lecture 9

“If you can draw the ATP flow and the cell-cycle wheel from memory, you are ready for half the paper.”

How to use this guide

1

Read one topic a day. Cover the diagram labels and name them aloud.

2

Rebuild the cheat sheet (p.9) from memory. What you miss is your next study block.

3

Take the quiz timed — 30 minutes — then mark it with the key on p.12.

Your 7-day countdown

Thu 16Topic 01 · cell structure

Fri 17Topic 02 · membrane & transport

Sat 18Topic 03 · respiration (both pages)

Sun 19Topic 04 · photosynthesis

Mon 20Topic 05 · cell cycle

Tue 21Cheat sheet from memory + quiz

Wed 22Fix the misses. Sleep 8 hours.

BIO 201 · Cell Biology · Midterm 1 02Contents

BIO 201 · Midterm Study Guide

01

Topic 1 · Lecture 4

Cell structure & organelles

**15%**of the exam

A eukaryotic cell divides its work between membrane-bound organelles. The nucleus keeps the DNA, the endomembrane system (ER → Golgi → vesicles) makes and ships proteins and lipids, and mitochondria make ATP. Prokaryotes have no nucleus and no membrane-bound organelles, but they do have ribosomes.

Fig 1.1 · Animal cell, cut open. Plant cells add a cellulose cell wall, chloroplasts and a large central vacuole.

Key terms

Organelle

A structure with a specific job, often wrapped in its own membrane.

Endomembrane system

ER, Golgi, lysosomes and vesicles, linked by vesicle traffic.

Ribosome

Makes proteins. 80S in eukaryotes, 70S in prokaryotes. No membrane.

Cytoskeleton

Protein fibres that give shape and move things.

Remember this

Rough ER = ribosomes = proteins for export or membranes.

Smooth ER = lipids, detox, Ca2+ storage. Liver cells are full of it.

Mnemonic · secretion

Really Good Vans Move

Rough ER → Golgi → Vesicle → Membrane (exocytosis)

Prokaryote vs eukaryote

	Prokaryote	Eukaryote
Nucleus	No · nucleoid	Yes
Organelles	None with membranes	Many
Ribosomes	70S	80S
DNA	One circular	Several linear
Size	1–10 µm	10–100 µm
Example	E. coli	You, oak, yeast

Concept map · how a secreted protein is made

Nucleusgene → mRNA

exits pore→

Rough ERribosome builds protein

vesicle→

Golgimodify, tag, sort

vesicle→

Plasma membraneexocytosis

→

Outsidee.g. insulin

Topic 1 of 5 · Cell structure & organelles 03Lecture 4

BIO 201 · Midterm Study Guide

02

Topic 2 · Lecture 5

Membrane & transport

**20%**of the exam

The membrane is a fluid mosaic: a phospholipid bilayer with proteins floating in it. Heads are hydrophilic and face water; tails are hydrophobic and hide inside. So it is selectively permeable: O2 and CO2 slip through; ions and polar molecules need a protein.

→Four ways across, from free to costly

Osmosis · where water goes

Water moves toward the side with more solute. Plant cells do not burst in hypotonic water — the cell wall makes them firm (turgid).

Remember this

Passive: down the gradient, free.
Active: against it, costs ATP.

Na+/K+ pump: 3 out, 2 in.

Mnemonic · tonicity

Hypo makes the cell swell like a hippo

Key terms

Concentration gradient

A difference in solute concentration between two regions.

Osmosis

Diffusion of water across a selectively permeable membrane.

Aquaporin

Channel protein that lets water through fast.

Topic 2 of 5 · Plasma membrane & transport 04Lecture 5

BIO 201 · Midterm Study Guide

03

Topic 3 · Lectures 6–7 · part 1 of 2

Cellular respiration

**25%**of the exam
biggest topic

Respiration takes the energy stored in glucose and saves it as ATP. It runs in four stages: one in the cytosol, three in the mitochondrion. Glucose is oxidised to CO2; O2 is reduced to water at the very end.

C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + ~30–32 ATP

Fig 3.1 · Mitochondrion, cut lengthwise. Folding the inner membrane into cristae gives more surface for the electron transport chain.

4The four stages, in order

1

Glycolysis

Cytosol · no O₂ needed

Glucose (6C) is split into 2 pyruvate (3C).

Net 2 ATP · 2 NADH

2

Pyruvate oxidation

Matrix

Each pyruvate loses a CO₂ and becomes acetyl-CoA.

2 NADH · 2 CO₂

3

Krebs cycle

Matrix · 2 turns

Acetyl-CoA joins oxaloacetate; the carbons leave as CO₂.

2 ATP · 6 NADH · 2 FADH₂ · 4 CO₂

4

Oxidative phosphorylation

Inner membrane

NADH and FADH₂ feed the ETC; ATP synthase uses the H⁺ gradient.

≈ 26–28 ATP · H₂O

Mnemonic · the stages

Get Paid, Keep Earning

Glycolysis → Pyruvate oxidation → Krebs → Electron transport

Mnemonic · Krebs intermediates

Citrate Is Krebs’ Starting Substrate For Making Oxaloacetate

citrate · isocitrate · α-ketoglutarate · succinyl-CoA · succinate · fumarate · malate · OAA

Topic 3 of 5 · Cellular respiration · continued → 05Lectures 6–7

BIO 201 · Midterm Study Guide

03

Topic 3 · part 2 of 2

Follow the ATP

~32ATP per glucose

1ATP yield, stage by stage

2Chemiosmosis: the H⁺ waterfall

Complexes I, III and IV pump H⁺ out. H⁺ flows back through ATP synthase and turns its rotor to make ATP.

No oxygen? Fermentation

	Lactic acid	Alcohol
Who	Muscle cells, bacteria	Yeast
Makes	Lactate	Ethanol + CO₂
ATP	2 per glucose (glycolysis only)
Purpose	Regenerate NAD⁺ so glycolysis keeps going

Remember this

O2 is used only at Complex IV, as the final electron acceptor. No O2 → the chain backs up → no gradient → almost no ATP.

Exhaled CO2 comes from pyruvate ox. + Krebs.

Key terms

NAD⁺ / NADH

Electron carrier: oxidised / reduced form.

Substrate-level phosph.

Enzyme moves a phosphate straight onto ADP.

Chemiosmosis

ATP made by H⁺ flowing down its gradient.

Concept map · where the energy goes

Glucoseenergy in bonds

oxidised→

NADH, FADH₂carry electrons

ETC→

H⁺ gradientstored energy

flows back→

ATP synthaserotary motor

→

ATP~32 / glucose

Topic 3 of 5 · Cellular respiration 06Lectures 6–7

BIO 201 · Midterm Study Guide

04

Topic 4 · Lecture 8

Photosynthesis

**20%**of the exam

Chloroplasts turn light energy into chemical energy. The light reactions in the thylakoid membranes make ATP and NADPH and release O2. The Calvin cycle in the stroma spends that ATP and NADPH to build sugar from CO2. It is respiration run backwards.

6 CO2 + 6 H2O + light → C6H12O6 + 6 O2

2Two stages, one loop

Photosynthesis vs respiration

	Photosynth.	Respiration
Where	Chloroplast	Cytosol + mito.
Energy	Stored	Released
Uses	CO₂ + H₂O	Glucose + O₂
Makes	Glucose + O₂	CO₂ + H₂O
Carrier	NADPH	NADH, FADH₂
Both	ETC + H⁺ gradient + ATP synthase

Remember this

O2 comes from water (split at PSII), not CO2.

Chlorophyll absorbs red + blue, reflects green.

Mnemonic

Light Loads, Calvin Cashes in

Key terms

Rubisco

Enzyme that fixes CO₂ onto RuBP. Most common protein on Earth.

Photosystem

Chlorophyll + proteins that catch light and excite electrons.

G3P

3-carbon sugar made by Calvin. 2 G3P → 1 glucose.

Per glucose

6 turns: 6 CO₂, 18 ATP, 12 NADPH.

Topic 4 of 5 · Photosynthesis 07Lecture 8

BIO 201 · Midterm Study Guide

05

Topic 5 · Lecture 9

Cell cycle & mitosis

**20%**of the exam

A cell spends most of its life in interphase, growing and copying its DNA. Then mitosis splits the copied chromosomes evenly, and cytokinesis splits the cytoplasm. Result: two identical diploid daughter cells. Checkpoints stop the cycle if something is wrong.

✓Three checkpoints

• G1 checkpoint (restriction point) — is the cell big enough, is the DNA intact? If not, it rests in G0.
• G2/M checkpoint — was all the DNA copied correctly?
• Spindle checkpoint (in metaphase) — is every chromosome attached to the spindle?

Cyclins switch on CDKs to push the cell past each checkpoint. p53 stops the cycle when DNA is damaged. Cancer = checkpoints that no longer work.

Remember this

Human cell after S phase: still 46 chromosomes, but 92 chromatids. Count the centromeres, not the arms.

5Mitosis, step by step

Prophase

Chromosomes condense; spindle forms; nuclear envelope breaks down.

Metaphase

Chromosomes line up on the middle plate. Spindle checkpoint.

Anaphase

Sister chromatids separate and move to opposite poles.

Telophase

Two new nuclear envelopes form; chromosomes unwind.

Cytokinesis

Cleavage furrow (animal) or cell plate (plant) splits the cell.

Mnemonic · the phases

I Prefer My Avocado Toast

Interphase → Prophase → Metaphase → Anaphase → Telophase

Phase tricks

Metaphase = Middle
Anaphase = Apart
Telophase = Two nuclei

Mitosis → 2 identical diploid (2n) cells. Meiosis (4 haploid cells) is Lecture 10 — not on this exam.

Key terms

Sister chromatids

Two identical copies joined at the centromere.

Kinetochore

Protein on the centromere where spindle fibres attach.

Topic 5 of 5 · Cell cycle & mitosis 08Lecture 9

BIO 201 · Midterm Study Guide Cheat sheet

The whole midterm

on one page.

rewrite this from
memory the night before ✎

_01_Cell structure

• Nucleus DNA · nucleolus makes ribosomes
• Rough ER proteins · smooth ER lipids, detox
• Golgi modifies, sorts, ships · lysosome digests
• Mitochondria ATP · chloroplasts (plants) sugar
• Prokaryotes: no nucleus, 70S ribosomes
• Plants add cell wall, chloroplasts, big vacuole

RER → Golgi → vesicle → membrane

_02_Membrane & transport

• Fluid mosaic: bilayer + proteins + cholesterol
• O₂, CO₂ diffuse freely; ions need proteins
• Passive (down gradient, no ATP): simple, facilitated, osmosis
• Active (against, ATP): Na⁺/K⁺ pump = 3 out, 2 in
• Hypertonic shrinks · hypotonic swells
• Bulk: endocytosis in, exocytosis out

Water follows solute

_03_Cellular respiration

• Glycolysis · cytosol · 2 ATP, 2 NADH
• Pyruvate ox. · matrix · 2 NADH, 2 CO₂
• Krebs · matrix · 2 ATP, 6 NADH, 2 FADH₂
• ETC · inner membrane · O₂ final acceptor
• No O₂ → fermentation, 2 ATP only
• ATP synthase runs on the H⁺ gradient

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + ~32 ATP

_04_Photosynthesis

• Light reactions · thylakoid · make ATP, NADPH, O₂
• O₂ comes from splitting H₂O at PSII
• Calvin · stroma · rubisco fixes CO₂ → G3P
• 6 turns / glucose = 18 ATP + 12 NADPH
• Chlorophyll absorbs red + blue
• Same toolkit as mito: ETC + ATP synthase

6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂

_05_Cell cycle & mitosis

• G1 grow → S copy DNA → G2 prepare → M divide
• P condense · M middle · A apart · T two nuclei
• Checkpoints: G1, G2/M, spindle
• Cyclins + CDKs drive it; p53 stops it
• Result: 2 identical diploid cells
• Cytokinesis: furrow (animal), plate (plant)

I Prefer My Avocado Toast

_#_Numbers to know

~32ATP per glucose, aerobic

2ATP per glucose, fermentation

3 : 2Na⁺ out : K⁺ in per ATP

46 / 92chromosomes / chromatids in G2

2.5 · 1.5ATP per NADH · FADH₂

6Calvin turns per glucose

Top 5 traps

1O₂ is used at the END of respiration, not the start

2Photosynthesis O₂ comes from H₂O, not CO₂

3Water moves toward MORE solute

4S phase doubles chromatids, not chromosomes

5Glycolysis needs no O₂ and no mitochondria

Cheat sheet · all five topics 09Review

BIO 201 · Midterm Study Guide Practice quiz · 30 min

?

Practice quiz · part A

Test yourself

Your score**____ / 32**

PART AMultiple choice · 1 point each · fill in one bubble

1

Which organelle modifies, sorts and packages proteins for secretion?

Rough ER Golgi apparatus Lysosome Smooth ER

2

A cell that makes large amounts of steroid hormones will have a lot of:

Rough ER Smooth ER Lysosomes Centrioles

3

Which structure is found in BOTH prokaryotic and eukaryotic cells?

Nucleus Mitochondria Ribosomes Endoplasmic reticulum

4

Which molecule crosses a phospholipid bilayer most easily without a protein?

Na⁺ Glucose O₂ Cl⁻

5

A red blood cell (≈0.9% salt inside) is put in 3% salt water. The cell will:

Swell and burst Shrink Stay the same Pump water in with ATP

6

For each ATP used, the Na⁺/K⁺ pump moves:

3 Na⁺ out, 2 K⁺ in 2 Na⁺ out, 3 K⁺ in 3 Na⁺ in, 2 K⁺ out 1 Na⁺ out, 1 K⁺ in

7

Facilitated diffusion is different from active transport because it:

Needs ATP Moves solutes down their gradient Uses no proteins Only moves water

8

Where does glycolysis take place?

Mitochondrial matrix Inner mitochondrial membrane Cytosol Intermembrane space

9

The final electron acceptor of the electron transport chain is:

NAD⁺ O₂ CO₂ Pyruvate

10

Most of the ATP made from one glucose comes from:

Glycolysis The Krebs cycle Fermentation Oxidative phosphorylation

11

The O₂ released by photosynthesis comes from:

CO₂ Glucose H₂O RuBP

12

The Calvin cycle uses which products of the light reactions?

O₂ and glucose ATP and NADPH CO₂ and H₂O ADP and NADP⁺

13

In which phase are sister chromatids pulled to opposite poles?

Prophase Metaphase Anaphase Telophase

14

A human cell in G2 contains:

46 chromosomes, 46 chromatids 46 chromosomes, 92 chromatids 92 chromosomes, 92 chromatids 23 chromosomes, 46 chromatids

15

Which enzyme fixes CO₂ in the Calvin cycle?

ATP synthase Rubisco Hexokinase DNA polymerase

16

Muscle cells that run low on O₂ regenerate NAD⁺ by:

Lactic acid fermentation Alcohol fermentation The Krebs cycle Photosystem II

Practice quiz · part A of 2 · answers on page 12 10Quiz

BIO 201 · Midterm Study Guide Practice quiz · 30 min

?

Practice quiz · parts B & C

Draw it, explain it

16points

PART BDiagram · Q17 · 1 point per sketch · name the phase of mitosis

A

B

C

D

PART CShort answer · write in full sentences

18

Cyanide blocks Complex IV. Explain why a cell poisoned with cyanide makes almost no ATP, even though glycolysis can still run.3 pts

19

A plant cell and an animal cell are both put in distilled water. Describe what happens to each and why they end up different.3 pts

20

Trace a secreted protein (such as insulin) from its gene to the outside of the cell. Name four structures in order.4 pts

21

Give two ways photosynthesis and cellular respiration mirror each other.2 pts

Practice quiz · part B & C · answers on page 12 11Quiz

BIO 201 · Midterm Study Guide Answer key

✓

Mark it, then fix it

Answer key & exam day

26+= ready

PART AMultiple choice

1B

2B

3C

4C

5B

6A

7B

8C

9B

10D

11C

12B

13C

14B

15B

16A

2 · Steroids are lipids, and lipids are made in the smooth ER.

4 · O₂ is small and non-polar. Ions and glucose need a channel or carrier.

5 · The outside is hypertonic, so water leaves and the cell shrinks.

10 · ATP synthase makes ≈ 26–28 of the ~32 ATP.

14 · S phase doubles the chromatids, not the chromosome count.

Part B (Q17) · A anaphase · B prophase · C telophase · D metaphase.

PART CModel answers

18 · Electrons cannot pass to O₂, so the chain stops and no more H⁺ is pumped. The H⁺ gradient runs down and ATP synthase stops. NADH cannot give up its electrons, so the Krebs cycle stops too. Glycolysis alone gives only 2 ATP per glucose — far too little.

19 · Water moves in by osmosis in both cells, because the inside has more solute. The animal cell swells and can burst (lysis). The plant cell swells until its cell wall pushes back — it becomes turgid but does not burst.

20 · Nucleus (gene → mRNA) → ribosome on rough ER (protein made, enters ER) → Golgi apparatus (modified and packaged) → vesicle → plasma membrane (exocytosis).

21 · Any two: the overall equations are reverses of each other; both use an ETC, an H⁺ gradient and ATP synthase; the products of one are the reactants of the other.

EXAM DAYChecklist

The night before

• Rewrite the cheat sheet from memory
• Redo every quiz question you missed
• Pack ID, two #2 pencils, eraser, water
• Sleep — memory sets overnight

The morning of

• Eat breakfast (your brain runs on glucose)
• Draw the ATP flow and cell-cycle wheel once
• Be at LSB 140 by 9:45

In the room

• Do the diagram first — 10% in 5 minutes
• Underline “NOT” and “EXCEPT” in questions
• Leave 10 minutes to check bubbles

26–32 Ready. Re-read the cheat sheet once and sleep.

18–25 Close. Re-do the topic page for every miss.

0–17 Rebuild. One topic per day, then retake the quiz.

Missed one? Re-read: Q1–3, 20 → p.3 · Q4–7, 19 → p.4 · Q8–10, 16, 18 → p.5–6 · Q11–12, 15, 21 → p.7 · Q13–14, 17 → p.8

Good luck — you have done the work. 12Answer key