Free GCSE Biology Question and Answers — Questions and Answers

Question 1: Which of the following does not help a plant survive in dry conditions?

Long roots
Small surface area
Large surface area (Correct answer)
Waxy leaves

Correct answer: Large surface area

Plants in dry conditions need to conserve water to survive. A large surface area, particularly for leaves, would increase the rate of transpiration, leading to excessive water loss through evaporation. Adaptations like long roots, small surface areas (e.g., needle-like leaves), and waxy cuticles all help reduce water loss, making a large surface area detrimental in arid environments.

Question 2: The metabolic rate is the speed at which chemical reactions occurs in the

Cells (Correct answer)
Stomach
Organs
Skin

Correct answer: Cells

Metabolic rate refers to the speed at which all the chemical reactions necessary to maintain life occur within an organism. These fundamental chemical processes, such as respiration and synthesis, primarily take place inside the cells of the body. Therefore, the metabolic rate is a direct measure of cellular activity and energy expenditure.

Question 3: Where do viruses reside?

On their own
In organs
On cells
Host cells (Correct answer)

Correct answer: Host cells

Viruses are obligate intracellular parasites, meaning they cannot replicate or carry out metabolic processes independently. They must infect and take over the machinery of a living host cell to reproduce. Outside of a host cell, viruses are inert and cannot function, making host cells their essential residence for activity and survival.

Question 4: Who made strides in in the field of vaccinations?

Pasteur
Jenner (Correct answer)
Einstein
Semmelweis

Correct answer: Jenner

Edward Jenner is credited with pioneering the concept of vaccines in the late 18th century. He observed that exposure to cowpox protected individuals from the deadly smallpox virus. His groundbreaking work involved inoculating people with cowpox material to confer immunity, laying the foundation for modern vaccination practices.

Question 5: What does the phrase "pathogen" mean?

A virus
A type of disease
A disease causing organism (Correct answer)
A disease

Correct answer: A disease causing organism

The term 'pathogen' refers specifically to any biological agent that causes disease or illness in its host. This includes various microorganisms such as bacteria, viruses, fungi, and parasites. It is the causative agent, not the disease itself, that is termed a pathogen.

Question 6: What is the major justification for avoiding antibiotic overuse?

It causes damage to the oesophagus
Dangerous strains of resistance bacteria may develop (Correct answer)
It kills the friendly bacteria in our gut so we must eat more yoghurt
They are expensive

Correct answer: Dangerous strains of resistance bacteria may develop

Overusing antibiotics creates a strong selective pressure, allowing naturally resistant bacteria to survive and multiply. This leads to the development and spread of dangerous antibiotic-resistant strains, making infections much harder to treat. This phenomenon, known as antibiotic resistance, is a major global health concern.

Question 7: What is the most likely outcome for an individual who is not adapted to their surroundings?

It will put on weight
It will become extinct
It will survive well
It will not survive (Correct answer)

Correct answer: It will not survive

Adaptation refers to the process by which organisms evolve traits that help them survive and reproduce in their specific environment. An individual not adapted to its surroundings will lack the necessary characteristics to cope with environmental challenges like finding food, avoiding predators, or tolerating climate conditions. Consequently, it will struggle to survive and pass on its genes.

Question 8: What impact does the carbon monoxide in cigar smoke have?

It destroys the ozone layer
It causes lung cancer
It reduces the oxygen carrying capacity of blood (Correct answer)
It adds to the green house effect

Correct answer: It reduces the oxygen carrying capacity of blood

Carbon monoxide (CO) is a toxic gas in cigar smoke that binds to hemoglobin in red blood cells much more readily and strongly than oxygen. This forms carboxyhemoglobin, effectively reducing the blood's ability to transport oxygen from the lungs to the body's tissues and organs. This oxygen deprivation can lead to serious health problems.

Question 9: Which illness was erroneously associated with the MMR vaccine?

Gout
Autism (Correct answer)
HIV
Lung cancer

Correct answer: Autism

The MMR (Measles, Mumps, Rubella) vaccine was erroneously linked to autism by a fraudulent study published in 1998. This study was later retracted due to scientific misconduct, and numerous large-scale, robust scientific investigations have since definitively proven there is no causal link between the MMR vaccine and autism. Despite this, the misinformation caused significant public concern.

Question 10: What term is given to the variable that is measured in an investigation?

Fair
Dependent (Correct answer)
Independent
Control

Correct answer: Dependent

In a scientific experiment, the dependent variable is the factor that is measured or observed by the researcher. Its value is expected to change as a result of manipulations made to the independent variable. Essentially, it is the outcome that is being investigated or tested.

Question 11: What function do antibiotics serve?

They kill plant cells
They kill white blood cells
They kill viruses
They kill bacteria (Correct answer)

Correct answer: They kill bacteria

Antibiotics are a class of antimicrobial drugs specifically designed to target and kill bacteria or inhibit their growth. They work by interfering with bacterial cellular processes or structures, such as cell wall synthesis or protein production, that are not present in human cells. This selective action makes them effective treatments for bacterial infections.

Question 12: Dietary protein is required because

For long term energy
For growth (Correct answer)
It gives immediate energy
It tastes nice

Correct answer: For growth

Dietary protein is crucial because it provides the body with amino acids, which are the fundamental building blocks for all tissues. These amino acids are essential for the growth, repair, and maintenance of cells, muscles, organs, and other bodily structures. Proteins also play vital roles in enzyme production, hormone synthesis, and immune function.

Question 13: The chemical that makes tobacco smoke addicting is

Tar
Nicotine (Correct answer)
Sugar
Salt

Correct answer: Nicotine

Nicotine is the primary psychoactive and highly addictive chemical found in tobacco smoke. When inhaled, it rapidly reaches the brain, stimulating the release of neurotransmitters like dopamine, which creates pleasurable sensations. This powerful effect on the brain's reward system is what drives the addictive nature of tobacco products.

Question 14: A vaccine generates white blood cells to produce

Heat
Antivaccines
Antibodies (Correct answer)
Antigens

Correct answer: Antibodies

A vaccine works by introducing a weakened or inactive form of a pathogen, or its components, to the immune system. This exposure stimulates specific white blood cells, particularly B lymphocytes, to produce antibodies. These antibodies are specialized proteins that recognize and neutralize the specific pathogen, providing immunity without causing the actual disease.

Question 15: The result of consuming too much saturated fat is

Promote muscle growth
It decreses blood pressure
It has no effect because it is excreted
To increase cholesterol (Correct answer)

Correct answer: To increase cholesterol

Consuming too much saturated fat can significantly increase the levels of low-density lipoprotein (LDL) cholesterol, often referred to as 'bad' cholesterol, in the blood. High LDL cholesterol contributes to the buildup of plaque in arteries, a process called atherosclerosis, which increases the risk of heart disease and stroke.

Question 16: Which of the following does not describe a virus?

They infect living cells
They respire (Correct answer)
They contain DNA
They contain protein

Correct answer: They respire

Viruses are obligate intracellular parasites, meaning they lack the cellular machinery to carry out metabolic processes like respiration independently. Instead, they must infect a host cell and hijack its machinery to replicate and produce new viral particles. While they contain genetic material and protein, they do not respire in the way living cells do.

Free GCSE Biology Question and Answers

Which of the following does not help a plant survive in dry conditions?