COMSATS NTS-based Test Biology and Computer Science (NAT-IM / NAT-ICS) Syllabus

What is the role of bile in digestion, and where is it produced and stored?

Bile emulsifies fats (breaks them into smaller droplets); it is produced by the liver and stored in the gallbladder.

What are the four chambers of the human heart?

Right atrium, right ventricle, left atrium, and left ventricle.

What is the function of the right side of the heart versus the left side?

The right side pumps deoxygenated blood to the lungs (pulmonary circulation); the left side pumps oxygenated blood to the rest of the body (systemic circulation).

What are the three types of blood vessels and their main functions?

Arteries carry blood away from the heart, veins carry blood toward the heart, and capillaries enable exchange of materials between blood and tissues.

Which blood cells carry oxygen, and which protein enables this?

Red blood cells (erythrocytes), using the protein haemoglobin.

What are the two main divisions of the human nervous system?

The central nervous system (brain and spinal cord) and the peripheral nervous system (nerves outside the CNS).

What is a neuron, and name its three main parts?

A neuron is a nerve cell that transmits impulses; its three main parts are the cell body (soma), dendrites, and axon.

What is a synapse?

A junction between two neurons (or a neuron and effector) across which a nerve impulse is transmitted, usually via neurotransmitters.

What is the main difference between the nervous system and the endocrine system in coordination?

The nervous system uses electrical impulses for fast, short-lived responses; the endocrine system uses hormones in the blood for slower, longer-lasting responses.

Which gland is called the 'master gland' and why?

The pituitary gland, because it secretes hormones that control many other endocrine glands.

Which hormone regulates blood sugar by lowering it, and which gland produces it?

Insulin, produced by the pancreas (islets of Langerhans, beta cells).

What is the overall word equation for aerobic respiration?

Glucose + oxygen → carbon dioxide + water + energy (ATP).

What is the difference between aerobic and anaerobic respiration?

Aerobic respiration uses oxygen and releases more energy (CO2 and water as products); anaerobic respiration occurs without oxygen and releases less energy (producing lactic acid in animals or ethanol and CO2 in yeast).

What is the main organ of gas exchange in humans, and where does exchange occur?

The lungs; gas exchange occurs in the alveoli (tiny air sacs).

What is excretion?

The removal of metabolic waste products (such as carbon dioxide, urea, and excess water/salts) from the body.

What is the main nitrogenous waste excreted by humans, and which organ produces it?

Urea, produced by the liver and excreted by the kidneys.

What is the functional unit of the kidney called?

The nephron.

State Mendel's Law of Segregation.

During gamete formation, the two alleles for a trait separate (segregate) so that each gamete carries only one allele of each gene.

State Mendel's Law of Independent Assortment.

Alleles of different genes assort (are distributed to gametes) independently of one another.

What is the difference between genotype and phenotype?

Genotype is the genetic makeup (allele combination) of an organism; phenotype is its observable physical/biochemical characteristics.

What is the difference between homozygous and heterozygous?

Homozygous means having two identical alleles for a gene (e.g., TT or tt); heterozygous means having two different alleles (e.g., Tt).

In a monohybrid cross between two heterozygotes (Tt x Tt), what is the phenotypic and genotypic ratio?

Phenotypic ratio 3:1 (dominant:recessive); genotypic ratio 1:2:1 (TT:Tt:tt).

What does DNA stand for, and what is its full chemical name?

DNA stands for deoxyribonucleic acid.

What are the four nitrogenous bases in DNA, and how do they pair?

Adenine, Thymine, Guanine, and Cytosine; adenine pairs with thymine (A-T) and guanine pairs with cytosine (G-C).

What is the shape of the DNA molecule, and who proposed it?

A double helix, proposed by James Watson and Francis Crick (1953).

What is the difference between DNA and RNA in terms of sugar and bases?

DNA has deoxyribose sugar and uses thymine; RNA has ribose sugar and uses uracil instead of thymine. RNA is usually single-stranded.

What is the theory of natural selection, as proposed by Charles Darwin?

Organisms with favorable heritable traits are more likely to survive and reproduce ('survival of the fittest'), passing those traits to offspring, leading to evolution over time.

What is the smallest unit of digital information, and what are its two possible values?

A bit (binary digit), which can be either 0 or 1.

How many bits are in one byte, and what does a byte typically represent?

8 bits; a byte typically represents one character.

What is the difference between hardware and software?

Hardware is the physical components of a computer (e.g., CPU, monitor, keyboard); software is the set of programs/instructions that tell the hardware what to do.

What are the two main components of the CPU, and what does each do?

The Arithmetic Logic Unit (ALU), which performs calculations and logical operations, and the Control Unit (CU), which directs and coordinates operations.

What is the difference between RAM and ROM?

RAM (Random Access Memory) is volatile, temporary read/write memory that loses data when power is off; ROM (Read Only Memory) is non-volatile, permanent memory that retains data without power.

What is the difference between system software and application software?

System software (e.g., the operating system) manages and runs the computer hardware; application software (e.g., word processors, browsers) performs specific tasks for the user.

What is an operating system, and name two examples?

An operating system is system software that manages computer hardware and software resources and provides services for programs; examples include Windows, Linux, macOS, and Android.

What is the difference between an input device and an output device, with one example of each?

An input device sends data into the computer (e.g., keyboard, mouse); an output device displays or sends data out (e.g., monitor, printer).