Year 8 Unit 7 Biology, Chemistry and Physics Revision

A collection of flashcards covering key concepts from Year 8 Unit 7 Biology, Chemistry, and Physics.

What are the three types of pathogens mentioned in the biology notes?

Fungi, Bacteria, and Viruses.

What is the structure of fungi compared to bacteria?

Fungi are multicellular (e.g., mushrooms), while bacteria are single-celled organisms.

What do antibiotics primarily target in bacterial infections?

Antibiotics target the cell wall of bacteria.

What is herd immunity?

Herd immunity is the resistance to the spread of contagious disease within a population if a sufficiently high proportion of individuals are immune, typically through vaccination.

Describe one first line defence mechanism of the human body.

Tears contain enzymes that break down bacterial cell walls.

What is the process called by which white blood cells engulf and digest bacteria?

Phagocytosis.

What is the role of lymphocytes in the immune system?

Lymphocytes produce antibodies that label microorganisms for destruction.

Why is penicillin significant in medical history?

Penicillin was the first antibiotic used and has saved millions of lives.

What can happen if antibiotics are overused?

Overuse can lead to antibiotic resistance, allowing bacteria to survive and multiply.

What does the pH scale measure?

The pH scale measures how acidic or alkaline a solution is, ranging from 0 to 14.

What is sound caused by?

Sound is caused by vibrations.

Explain how loudness is related to amplitude.

The loudness of a sound is directly related to the amplitude of the sound wave; higher amplitude means louder sounds.

Define the term compression in relation to sound waves.

Compression refers to the areas in a sound wave where particles are closer together due to the vibration.

What is the effect of acid rain on buildings?

Acid rain can corrode limestone and marble buildings, leading to increased wear and damage.

List one way to prevent the spread of disease.

Washing hands regularly.

What do chemical sterilization methods help avoid?

Chemical sterilization methods help avoid heat damage to some substances.

What is echolocation?

Echolocation is the biological sonar used by some animals, emitting calls and listening for echoes to identify objects around them.

What are the main components of the ear?

The outer ear, eardrum, ossicles (tiny bones), and cochlea.

What does the term 'neutral' mean in the context of solutions?

Neutral refers to a solution that is neither acidic nor alkaline, typically with a pH of 7.

What are the uses of ultrasound in medicine?

Ultrasound is used for diagnosing diseases and in prenatal scans.