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# NLN NEX SCIENCE EXAM
## COMPREHENSIVE PRACTICE EXAMINATION
### 2026-2027 EDITION | FIRST-TIME ATTEMPT
SUCCESS PACKAGE
### BASED ON NLN NEX EXAM FRAMEWORK
## TABLE OF CONTENTS
| Section | Domain | Questions |
|---------|--------|-----------|
| 1 | Cell Structure & Function | 1-15 |
| 2 | Cellular Processes & Metabolism | 16-30 |
| 3 | Genetics & Heredity | 31-45 |
| 4 | Evolution & Classification | 46-55 |
| 5 | Microbiology & Immunology | 56-70 |
| 6 | Anatomy: Skeletal & Muscular Systems | 71-85 |
| 7 | Anatomy: Cardiovascular & Respiratory Systems | 86-100 |
| 8 | Anatomy: Nervous & Endocrine Systems | 101-115 |
| 9 | Anatomy: Digestive, Urinary & Reproductive Systems | 116-130 |
| 10 | Physiology: Homeostasis & Organ System Function | 131-145 |
| 11 | Chemistry: Atomic Structure & Bonding | 146-155 |
| 12 | Chemistry: Reactions & Organic Compounds | 156-165 |
| 13 | Health, Wellness & Disease Prevention | 166-180 |
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## SECTION 1: CELL STRUCTURE & FUNCTION
### Questions 1-15
**Question 1**
Which organelle is responsible for ATP production through cellular respiration?
A) Ribosome
B) Golgi apparatus
C) Mitochondrion
D) Endoplasmic reticulum
**Correct Answer: C**
**Rationale:** Mitochondria are the site of aerobic cellular respiration, generating
ATP (energy) through the electron transport chain and oxidative phosphorylation.
They are often called the "powerhouses of the cell." Ribosomes synthesize
proteins, the Golgi apparatus modifies and packages proteins, and the endoplasmic
reticulum is involved in protein and lipid synthesis .
---
**Question 2**
Which of the following is the smallest functional and structural unit of life?
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A) Tissue
B) Organelle
C) Cell
D) Molecule
**Correct Answer: C**
**Rationale:** The cell is the smallest functional and structural unit of life. It is
composed of approximately 60% water and contains organelles that perform
specific functions. Tissues are groups of cells, and organs are groups of tissues .
---
**Question 3**
Which cellular structure is responsible for the synthesis of proteins?
A) Lysosome
B) Ribosome
C) Nucleus
D) Mitochondrion
**Correct Answer: B**
**Rationale:** Ribosomes are the cellular structures responsible for protein
synthesis, translating messenger RNA (mRNA) into polypeptide chains. They can
be found free in the cytoplasm or attached to the rough endoplasmic reticulum .
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**Question 4**
What is the primary function of the cell membrane?
A) Synthesize proteins
B) Store genetic material
C) Regulate the passage of substances into and out of the cell
D) Produce ATP
**Correct Answer: C**
**Rationale:** The cell membrane (plasma membrane) is a selectively permeable
barrier that regulates the movement of substances into and out of the cell. It
controls what enters and leaves the cell, maintaining internal homeostasis. The
nucleus stores genetic material, and mitochondria produce ATP .
---
**Question 5**
Which organelle contains digestive enzymes and is involved in breaking down
cellular waste and pathogens?
A) Peroxisome
B) Lysosome
C) Ribosome
D) Nucleus
# NLN NEX SCIENCE EXAM
## COMPREHENSIVE PRACTICE EXAMINATION
### 2026-2027 EDITION | FIRST-TIME ATTEMPT
SUCCESS PACKAGE
### BASED ON NLN NEX EXAM FRAMEWORK
## TABLE OF CONTENTS
| Section | Domain | Questions |
|---------|--------|-----------|
| 1 | Cell Structure & Function | 1-15 |
| 2 | Cellular Processes & Metabolism | 16-30 |
| 3 | Genetics & Heredity | 31-45 |
| 4 | Evolution & Classification | 46-55 |
| 5 | Microbiology & Immunology | 56-70 |
| 6 | Anatomy: Skeletal & Muscular Systems | 71-85 |
| 7 | Anatomy: Cardiovascular & Respiratory Systems | 86-100 |
| 8 | Anatomy: Nervous & Endocrine Systems | 101-115 |
| 9 | Anatomy: Digestive, Urinary & Reproductive Systems | 116-130 |
| 10 | Physiology: Homeostasis & Organ System Function | 131-145 |
| 11 | Chemistry: Atomic Structure & Bonding | 146-155 |
| 12 | Chemistry: Reactions & Organic Compounds | 156-165 |
| 13 | Health, Wellness & Disease Prevention | 166-180 |
,2|Page
## SECTION 1: CELL STRUCTURE & FUNCTION
### Questions 1-15
**Question 1**
Which organelle is responsible for ATP production through cellular respiration?
A) Ribosome
B) Golgi apparatus
C) Mitochondrion
D) Endoplasmic reticulum
**Correct Answer: C**
**Rationale:** Mitochondria are the site of aerobic cellular respiration, generating
ATP (energy) through the electron transport chain and oxidative phosphorylation.
They are often called the "powerhouses of the cell." Ribosomes synthesize
proteins, the Golgi apparatus modifies and packages proteins, and the endoplasmic
reticulum is involved in protein and lipid synthesis .
---
**Question 2**
Which of the following is the smallest functional and structural unit of life?
,3|Page
A) Tissue
B) Organelle
C) Cell
D) Molecule
**Correct Answer: C**
**Rationale:** The cell is the smallest functional and structural unit of life. It is
composed of approximately 60% water and contains organelles that perform
specific functions. Tissues are groups of cells, and organs are groups of tissues .
---
**Question 3**
Which cellular structure is responsible for the synthesis of proteins?
A) Lysosome
B) Ribosome
C) Nucleus
D) Mitochondrion
**Correct Answer: B**
**Rationale:** Ribosomes are the cellular structures responsible for protein
synthesis, translating messenger RNA (mRNA) into polypeptide chains. They can
be found free in the cytoplasm or attached to the rough endoplasmic reticulum .
, 4|Page
**Question 4**
What is the primary function of the cell membrane?
A) Synthesize proteins
B) Store genetic material
C) Regulate the passage of substances into and out of the cell
D) Produce ATP
**Correct Answer: C**
**Rationale:** The cell membrane (plasma membrane) is a selectively permeable
barrier that regulates the movement of substances into and out of the cell. It
controls what enters and leaves the cell, maintaining internal homeostasis. The
nucleus stores genetic material, and mitochondria produce ATP .
---
**Question 5**
Which organelle contains digestive enzymes and is involved in breaking down
cellular waste and pathogens?
A) Peroxisome
B) Lysosome
C) Ribosome
D) Nucleus
