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Unit notes and practice questions

Grade 12 Biology unit 1: Application of Biology

Everything here is for unit 1 of the Grade 12 Biology textbook: what the chapter covers, the short notes, practice questions with their answers, and the lesson video where one exists.

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7
Cards
10
Practice questions on unit 1
6–39
The textbook pages for unit 1

What unit 1 covers

  1. 1.Application in conservation of natural resources
  2. 2.Food and nutrition security
  3. 3.Creating conscious citizens and ensuring sustainable development
  4. 4.Applications in biotechnology

Short notes for unit 1

The cards filed under this chapter on the Grade 12 Biology page. Open one at a time.

Resource TypeDefinitionExamples
RenewableCapable of being produced indefinitely and replaced when managed carefullySun, wind, water, geothermal, biomass, crops, livestock, timber
Non-renewableFinite supplies that are not replaced at the speed they are used upMetals (gold, iron, platinum), fossil fuels (coal, oil, natural gas)

When you use it

Use when distinguishing between infinite and finite environmental supplies in conservation biology questions.

Watch out

Renewable biological resources such as forests and wildlife can still be permanently lost through extinction if mismanaged.

Drafted from Grade 12 Biology, pages 6-39, then checked twice before it went up

When you use it

Use when identifying whether a genetically altered plant or animal contains foreign DNA from another species.

Watch out

Every transgenic organism is a GMO, but not every GMO is transgenic. An organism is only transgenic if the inserted recombinant DNA comes from a completely different species.

Drafted from Grade 12 Biology, pages 6-39, then checked twice before it went up

When you use it

Use when explaining the distinct criteria that separate dietary calorie access from comprehensive health and nutritional sufficiency.

Watch out

Food security refers to physical and economic access to sufficient food, whereas nutrition security also requires clean water, sanitation, health care, and proper food utilization.

Drafted from Grade 12 Biology, pages 6-39, then checked twice before it went up

MicroorganismTypeApplication or Product
SpirulinaCyanobacteriumSingle-cell protein source harvested from water surfaces
Methylophilus methylotrophusBacteriumPruteen animal feed mass culture
Fusarium venenatumFungusMycoprotein meat substitute production
Streptococcus thermophilus and Lactobacillus bulgaricusBacteriaYogurt fermentation
SaccharomycesFungus (yeast)Fermentation of beer, wine, and distilled spirits

When you use it

Use when matching specific bacteria, cyanobacteria, or fungi to industrial and traditional fermented food products.

Watch out

Do not mix up the bacterial combinations for yogurt with those for acidophilus or Bulgarian milk.

Drafted from Grade 12 Biology, pages 6-39, then checked twice before it went up

When you use it

Use this when classifying natural resources into renewable and non-renewable categories.

Watch out

Renewable biological resources can still be depleted permanently if harvested faster than their reproduction and growth lag time.

Drafted from Grade 12 Biology, pages 6-39, then checked twice before it went up

When you use it

Use when identifying or describing the core pillars of sustainability according to the IUCN model.

Watch out

Sustainable development requires balancing all three overlapping dimensions: social equity, economic efficiency, and environmental preservation.

Drafted from Grade 12 Biology, pages 6-39, then checked twice before it went up

When you use it

Use this rule when distinguishing a transgenic organism from a general genetically modified organism (GMO).

Watch out

All transgenic organisms are GMOs, but an organism is transgenic only if the introduced gene comes from a different species.

Drafted from Grade 12 Biology, pages 6-39, then checked twice before it went up

Practice questions on unit 1

10 multiple-choice questions written against this chapter, each with its answer and the reason. Try one before you open the answer.

Question 1

Which of the following is classified as a non-renewable natural resource?

  1. A.Natural gas
  2. B.Sunlight
  3. C.Wind
  4. D.Timber
Show the answer and why

Answer: A Natural gas

Why

Non-renewable resources are finite substances that are not replaced at the speed they are used up, such as natural gas, coal, and metals.

Question 2

According to the textbook classification of malnutrition, what is stunting?

  1. A.Being too fat for height and age
  2. B.Being too thin for height
  3. C.Being too short for age
  4. D.Having high blood pressure
Show the answer and why

Answer: C Being too short for age

Why

Stunting is defined as being too short for age due to prolonged undernourishment.

Question 3

What is an organism called if it has received genetic material from a completely different species?

  1. A.Transgenic organism
  2. B.Single-cell protein
  3. C.Renewable organism
  4. D.Conscious organism
Show the answer and why

Answer: A Transgenic organism

Why

If an organism has received genetic material from a different species, it is called a transgenic organism.

Question 4

Which spiral-shaped cyanobacterium is harvested from lakes and ponds as a source of single-cell nutrient pellets?

  1. A.Fusarium venenatum
  2. B.Spirulina
  3. C.Saccharomyces
  4. D.Lactobacillus
Show the answer and why

Answer: B Spirulina

Why

Spirulina is a spiral-shaped cyanobacterium harvested from ponds and lakes and used as a nutrient-rich food supplement.

Question 5

Which bacterium is grown in mass culture to produce the animal feed called Pruteen?

  1. A.Methylophilus methylotrophus
  2. B.Fusarium venenatum
  3. C.Streptococcus thermophilus
  4. D.Lactobacillus acidophilus
Show the answer and why

Answer: A Methylophilus methylotrophus

Why

Pruteen is an animal feed produced by the mass culture of the bacterium Methylophilus methylotrophus.

Question 6

In the process of beer brewing, what is the name of the liquid extract separated from the mash before hops are added?

  1. A.Spirits
  2. B.Wort
  3. C.Mycoprotein
  4. D.Buttermilk
Show the answer and why

Answer: B Wort

Why

After cereal grains are mashed with hot water, the liquid extract separated from the mix is called wort.

Question 7

Which two microorganisms are added to milk to make yogurt?

  1. A.Streptococcus thermophilus and Lactobacillus bulgaricus
  2. B.Penicillium and Aspergillus
  3. C.Saccharomyces and Methylophilus methylotrophus
  4. D.Pediococcus cerevisiae and Fusarium venenatum
Show the answer and why

Answer: A Streptococcus thermophilus and Lactobacillus bulgaricus

Why

Yogurt is produced by adding Streptococcus thermophilus and Lactobacillus bulgaricus to milk.

Question 8

Why is sulfur dioxide added to grape juice during the commercial production of wine?

  1. A.To increase the sugar content of the juice
  2. B.To kill any wild yeasts that may be present
  3. C.To remove heavy metals from the soil
  4. D.To turn the grape juice into vinegar
Show the answer and why

Answer: B To kill any wild yeasts that may be present

Why

In wine making, grape juice is treated with sulfur dioxide to kill any wild yeasts already present before adding selected yeast strains.

Question 9

Before modern fermentation by propionic bacteria was introduced, where was vitamin B12 mainly obtained from?

  1. A.Barley mash
  2. B.Animal liver extract
  3. C.Citrus fruit peels
  4. D.Cyanobacteria mats
Show the answer and why

Answer: B Animal liver extract

Why

Previously, vitamin B12 (cyanocobalamin) was extracted from animal liver before microbial fermentation methods were developed.

Question 10

What type of fermentation is carried out by Lactobacillus plantarum and Pediococcus cerevisiae to preserve meat and give it a tangy flavor?

  1. A.Alcoholic distillation
  2. B.Heterolactic acid fermentation
  3. C.Homolactic sugar precipitation
  4. D.Acetic acid distillation
Show the answer and why

Answer: B Heterolactic acid fermentation

Why

Heterolactic acid fermentation by these bacteria helps preserve meats like salami and summer sausage while giving them a tangy flavor.

The app holds 12 questions on this unit, marked as you go. These are the first 10.

The textbook pages for unit 1

Unit 1 runs from page 6 to page 39 of the Ministry of Education edition.

Ministry of Education edition, English, 358 pages

Download the PDF

All Grade 12 Biology short notes

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