Science Grade 8: Digestive System Processes

Practice flashcards covering the parts, functions, processes, and inter-system relationships of the human digestive system based on the Grade 8 Science Lesson Exemplar.

What is the primary content standard for Grade 8 Science Quarter 1?

Learners learn that organ systems work together for the growth and survival of the organism.

What is the definition of a body system?

A group of organs working together to perform a certain function.

What is 'chyme'?

The semi-fluid mass of partially digested food and gastric juices formed in the stomach and passed into the small intestine.

What is the function of the enzyme amylase?

It is produced in the saliva and pancreas to break down carbohydrates into simpler sugars.

How is 'absorption' defined in the context of the digestive system?

The process by which digested nutrients are taken up by cells lining the digestive tract and transported into the bloodstream.

What is 'peristalsis'?

The involuntary muscle contractions that propel food and liquid through the digestive tract.

What is the function of the enzyme lipase?

It breaks down fats into fatty acids and glycerol.

What are enzymes?

Biological molecules that speed up chemical reactions, such as the breakdown of food into smaller molecules for absorption.

What are 'villi'?

Small finger-like projections in the lining of the small intestine that increase its surface area for absorption.

What is the difference between mechanical and chemical digestion?

Mechanical digestion is the physical breakdown of food by chewing or churning, while chemical digestion breaks down food into simpler chemical compounds through enzymatic reactions.

What are 'microvilli'?

Tiny hair-like structures on the surface of villi that further increase the surface area available for nutrient absorption.

What is the function of protease?

An enzyme that breaks down proteins into amino acids.

What is a 'bolus'?

A rounded mass of food that has been chewed and mixed with saliva in the mouth, ready to be swallowed.

What are the primary organs involved in the pathway of food?

Mouth, Pharynx, Esophagus, Stomach, Small Intestine, Large Intestine, Rectum, and Anus.

What are the accessory organs of the digestive system mentioned in the lesson?

Pancreas, Liver, and Gall Bladder.

What is a common misconception about the location of digestion?

That digestion only happens in the stomach; it actually begins in the mouth and continues in the small intestine.

What actually causes most stomach ulcers according to the lesson?

Bacterial infection ($Helicobacter\,pylori$) or prolonged use of nonsteroidal anti-inflammatory drugs (NSAIDs), rather than spicy food.

What is the primary function of the small intestine?

The absorption of nutrients.

What is the primary function of the large intestine?

The absorption of water and minerals.

What is the role of the liver and gallbladder in digestion?

Producing and storing bile, which is used for emulsifying fats.

How does the digestive system interact with the respiratory system?

The digestive system furnishes nutrients to support the function of the diaphragm in facilitating breathing.

How does the circulatory system interact with the digestive system?

By transporting nutrients absorbed by the digestive system to the rest of the body, including the heart.

How does the nervous system regulate digestion?

By controlling muscle contractions and transmitting signals to coordinate bodily functions.

What occurs during the 'elimination' process?

Waste products are expelled from the body.

What is the purpose of mucus secretion in the digestive tract?

To lubricate food.