Describe the fresh stage of decomposition.

The initial stage immediately after death where there is no visible decomposition; internal autolysis begins but external appearance remains largely unchanged.

What characterises the bloat stage of decomposition?

Gases produced by bacterial metabolism accumulate in body cavities, causing the body to swell and become distended.

What occurs during the active decay stage of decomposition?

The greatest mass loss occurs as tissues liquefy and are consumed by insects and bacteria; strong odours are released.

What remains during the dry/skeletal remains stage of decomposition?

Only bones, cartilage, and dried skin remain; decomposition is very slow at this stage.

Edexcel A-Level Biology A 9BN0

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Immunity, Infection and Forensics

Decomposition, succession and forensic entomology

3 things to know
Papers 1 and 3

Overview

Recall questions on the stages of decomposition, the succession of insects on a corpse, and how blowfly larvae are used to estimate time since death.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Key term

Describe the advanced decay stage of decomposition.

Key term

Why is temperature important when using insect larvae to estimate time of death?

Process

What physical process in a corpse can be examined to estimate time of death?

Questions from this subtopic

Each one with the model answer underneath.

1
What physical process in a corpse can be examined to estimate time of death?
Model answer
The extent of decomposition of the body.
2
Describe the fresh stage of decomposition.
Model answer
The initial stage immediately after death where there is no visible decomposition; internal autolysis begins but external appearance remains largely unchanged.
3
What characterises the bloat stage of decomposition?
Model answer
Gases produced by bacterial metabolism accumulate in body cavities, causing the body to swell and become distended.
4
What occurs during the active decay stage of decomposition?
Model answer
The greatest mass loss occurs as tissues liquefy and are consumed by insects and bacteria; strong odours are released.
5
Describe the advanced decay stage of decomposition.
Model answer
Most soft tissue has been removed; decomposition slows significantly and remaining tissue dries out.
6
What remains during the dry/skeletal remains stage of decomposition?
Model answer
Only bones, cartilage, and dried skin remain; decomposition is very slow at this stage.

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