Nutrition | Jamb Biology

Jamb(UTME) tutorial on modes of nutrition

50 Points on Mode of Nutrition:

Mode of Nutrition

1. Definition: Nutrition is how organisms obtain food and energy to survive.

2.Types of Nutrition:

• Autotrophic Nutrition: Organisms make their own food.
• Heterotrophic Nutrition: Organisms rely on others for food.
  
  paragraph

Autotrophic Nutrition

3. Found in plants, algae, and some bacteria.
4. Autotrophs use sunlight (photosynthesis) or chemicals (chemosynthesis) to make food.
5. Requires simple substances like carbon dioxide and water.
6. Primary producers in ecosystems.
7. Examples: Green plants, cyanobacteria, sulfur bacteria.
   
   paragraph

Heterotrophic Nutrition

8. Found in animals, fungi, and non-green plants.
9. Organisms depend on plants, animals, or dead matter for food.
10. Involves ingestion, absorption, or parasitism.
11. Consumers in ecosystems.
12. Examples: Humans, lions, mushrooms, dodder plant.
    
    paragraph

Categories of Heterotrophic Nutrition

13. Holozoic Nutrition: Eating and digesting solid food (e.g., humans).
14. Parasitic Nutrition: Feeding on a host (e.g., dodder, mistletoe).
15. Saprophytic Nutrition: Feeding on dead matter (e.g., fungi, bacteria).
16. Symbiotic Nutrition: Two organisms benefit each other (e.g., lichens).
17. Carnivorous Nutrition: Found in plants like Venus Flytrap and pitcher plant.
    
    paragraph

Examples of Nutrition in Plants

Flowering Plants:

18. Autotrophic: Sunflower, mango tree, wheat.
19. Heterotrophic: Dodder (parasitic plant), Indian pipe (saprophytic plant).
    
    paragraph

Non-Flowering Plants:

20. Autotrophic: Algae, mosses, ferns.
21. Heterotrophic: Mushrooms (saprophytic fungi), lichen (symbiotic association).
    
    paragraph

Photosynthesis

22. A process in autotrophic nutrition.
23. Converts sunlight, water, and carbon dioxide into food.
24. Requires chlorophyll.
25. Produces oxygen as a byproduct.
26. Examples: Green plants, algae, cyanobacteria.
    
    paragraph

Chemosynthesis

27. Another process in autotrophic nutrition.
28. Uses energy from inorganic chemicals instead of sunlight.
29. Found in dark environments like deep-sea vents.
30. Produces food and inorganic byproducts (e.g., nitrates or sulfates).
31. Examples: Sulfur bacteria, iron bacteria.
    
    paragraph

Relationship with Ecosystems

32. Autotrophs are the primary producers of energy.
33. Heterotrophs are the consumers in food chains.
34. Carnivorous plants thrive in nutrient-poor soils.
35. Decomposers (fungi, bacteria) recycle nutrients into the soil.
36. Nitrogen-fixing bacteria help plants grow.
    
    paragraph

Carnivorous and Parasitic Plants**

37. Venus Flytrap: A carnivorous plant that traps insects.
38. Pitcher Plant: Another carnivorous plant found in nutrient-poor environments.
39. Dodder Plant: A parasitic flowering plant that feeds on host plants.
    
    paragraph

Fungi and Saprophytes

40. Mushrooms and other fungi feed on dead organic material.
41. Saprophytes help decompose dead matter and enrich the soil.
    
    paragraph

Symbiosis Examples

42. Lichens: A partnership between fungi and algae.
43. Mycorrhizae: Fungi that live on plant roots, helping absorb nutrients.
    
    paragraph

Adaptations in Nutrition

44. Plants adapt to poor soils by being carnivorous (e.g., Sundew).
45. Parasites adapt to live on or in a host.
    
    paragraph

Role of Nutrition in Ecosystems

46. Energy flows from autotrophs to heterotrophs in food chains.
47. Decomposers break down dead material, completing the nutrient cycle.
48. All organisms depend on nutrition for energy and survival.
    
    paragraph

Photosynthetic and Chemosynthetic Examples

49. Photosynthetic Organisms: Green plants, algae, cyanobacteria.
50. Chemosynthetic Organisms: Sulfur bacteria, nitrifying bacteria in the ocean floor.
    
    paragraph

Jamb(UTME) tutorial on types of nutrition

Types of Nutrition

1. Nutrition is the process by which organisms obtain food and energy for survival.
2. Autotrophic Nutrition: Organisms make their own food using sunlight or chemicals.
3. Examples of autotrophs: Green plants, algae, and cyanobacteria.
4. Heterotrophic Nutrition: Organisms rely on other organisms for food.
5. Examples of heterotrophs: Animals, fungi, and non-green plants.
   
   paragraph

Holozoic Nutrition

6. Definition: Involves ingestion, digestion, and absorption of solid food.
7. Common in: Humans, animals like sheep, and other higher organisms.
8. Steps in Holozoic Nutrition:
   • Ingestion: Eating food.
   • Digestion: Breaking food into smaller molecules.
   • Absorption: Nutrients absorbed into the bloodstream.
   • Assimilation: Nutrients used for energy and growth.
   • Egestion: Removal of undigested waste.
9. Examples:
   • Sheep: Herbivores, eat grass and plants for energy.
   • Humans: Omnivores, consume plants and animals.
10. Nutritional Value:
    • Sheep: Grass is rich in fiber but low in calories; supports digestion.
    • Humans: Mixed diet provides proteins, carbohydrates, fats, vitamins, and minerals.
      
      paragraph

Parasitic Nutrition

11. Definition: One organism (parasite) feeds on another organism (host).
12. Host: The organism that provides nutrients to the parasite.
13. Parasites often harm their hosts.
14. Examples:
    • Roundworm: A parasite in human intestines, feeds on digested nutrients.
    • Tapeworm: A flatworm that absorbs nutrients directly from the host's gut.
    • Loranthus: A parasitic plant that attaches to trees to suck nutrients.
15. Nutritional Value:
    • Roundworm and tapeworm: Provide no nutritional value but deplete the host's nutrients.
    • Loranthus: Competes with host plants, offers limited ecological value.
      
      paragraph

Saprophytic Nutrition

16. Definition: Feeding on dead and decaying organic matter.
17. Found in decomposers: Break down complex organic material into simpler forms.
18. Examples:
    • Rhizopus: A fungus that grows on bread and other decaying materials.
    • Mushroom: A fungus that feeds on dead plant material.
19. Role in ecosystems: Decomposers recycle nutrients back into the soil.
20. Nutritional Value:
    • Rhizopus: Helps decompose organic material but isn’t directly edible.
    • Mushrooms: Rich in proteins, vitamins, and minerals, making them highly nutritious.
      
      paragraph

Carnivorous Plants

21. Definition: Plants that trap and digest insects or small animals to obtain nutrients.
22. Adaptation: Common in nutrient-poor soils where nitrogen is scarce.
23. Examples:
    • Sundew: Uses sticky tentacles to trap insects.
    • Bladderwort: Aquatic plant with traps that suck in small prey.
24. Steps in Carnivorous Nutrition:
    • Prey capture: Specialized structures trap insects.
    • Digestion: Enzymes break down prey into simpler compounds.
    • Absorption: Nutrients absorbed into the plant.
25. Nutritional Value:
    • Sundew: Adds nitrogen and phosphorus to the plant’s diet.
    • Bladderwort: Enhances growth by supplementing essential minerals.
      
      paragraph

Comparison of Types of Nutrition

Holozoic Nutrition:

26. Found in animals like sheep and humans.
27. Requires a digestive system.
28. Nutritional value comes from the diversity of food consumed.
    
    paragraph

Parasitic Nutrition:

29. Found in parasites like roundworm, tapeworm, and Loranthus.
30. Relies entirely on a host for nutrients.
31. Little or no nutritional value for the host.
    
    paragraph

Saprophytic Nutrition:

32. Found in fungi like Rhizopus and mushrooms.
33. Breaks down dead organic matter.
34. Mushrooms provide high nutritional value when consumed.
    
    paragraph

Carnivorous Plants:

35. Found in plants like Sundew and Bladderwort.
36. Helps plants survive in poor soil.
37. Insects are a source of nitrogen and other nutrients.
    
    paragraph

Ecological Importance

38. Holozoic organisms maintain food chains by consuming plants and animals.
39. Parasitic organisms control population sizes but can harm ecosystems.
40. Saprophytes recycle nutrients and enrich soil fertility.
41. Carnivorous plants adapt to nutrient-poor environments, maintaining biodiversity.
    
    paragraph

Interesting Facts

42. Sheep’s digestive system is adapted for cellulose digestion.
43. Humans' diet influences their health and energy levels.
44. Roundworms and tapeworms can cause malnutrition in hosts.
45. Loranthus reduces the growth of host plants by stealing nutrients.
46. Rhizopus spreads quickly in warm, moist conditions.
47. Mushrooms are a popular source of plant-based protein.
48. Sundew can bend its tentacles to trap prey.
49. Bladderwort uses vacuum pressure to suck prey into its traps.
50. Each mode of nutrition is essential for the balance of ecosystems.
    paragraph

Jamb(UTME) tutorial on plant nutrition

Photosynthesis Basics

1. Definition: Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy stored in glucose.
2. Importance: Provides food and oxygen, forming the base of the food chain.
3. Site: Takes place in chloroplasts, especially the thylakoid membranes (light reaction) and stroma (dark reaction).
4. Overall Equation: $6CO_2 + 6H_2O + light \to C_6H_{12}O_6 + 6O_2$.
5. Key Requirements: Light, chlorophyll, carbon dioxide $(CO_2)$, and water $(H_2O)$.
6. Chlorophyll: Green pigment that absorbs sunlight.
7. Energy Source: Sunlight powers the process.
8. Stages: Divided into light reactions and dark reactions (Calvin Cycle).
   
   paragraph

Light Reaction

9. Definition: The stage where light energy is converted into chemical energy (ATP and NADPH).
10. Location: Occurs in the thylakoid membranes of chloroplasts.
11. Inputs: Light, water, ADP, and NADP+.
12. Outputs: Oxygen (released as a byproduct), ATP, and NADPH.
13. Photolysis: Splitting of water molecules into oxygen, protons, and electrons.
14. Role of Chlorophyll: Captures light energy to drive electron transfer.
    
    paragraph

Dark Reaction (Calvin Cycle)2

15. Definition: A light-independent stage where glucose is synthesized using ATP and NADPH.
16. Location: Occurs in the stroma of chloroplasts.
17. Inputs: Carbon dioxide $(CO_2)$, ATP, and NADPH.
18. Outputs: Glucose, ADP, and NADP+.
19. Carbon Fixation: Enzyme Rubisco helps incorporate $CO_2$ into organic molecules.
20. Cycle Nature: Recycles intermediates to ensure continuous glucose production.
    
    paragraph

Necessity of Light, Carbon Dioxide, and Chlorophyll

21. Light: Provides energy for splitting water and generating ATP and NADPH.
22. Carbon Dioxide: Provides the carbon needed to form glucose.
23. Chlorophyll: Essential pigment for capturing sunlight.
    
    paragraph
    Experiment to Demonstrate Necessity of light, Carbon dioxide and chlorophyll:
24. Cover a leaf with black paper to block light; the area will not produce starch.
25. Place a plant in a $CO_2$-free environment; no starch will form.
26. Use a variegated leaf (part green, part white); starch forms only in green areas containing chlorophyll.
    
    paragraph

Detecting Starch as Evidence of Photosynthesis

27. Boil the leaf to stop photosynthesis.
28. Immerse in alcohol to remove chlorophyll.
29. Rinse in hot water to soften the leaf.
30. Add iodine solution; starch turns blue-black.
31. Only areas exposed to light will test positive for starch.
    
    paragraph

Macro- and Micro-Elements Required by Plants

32. Macronutrients: Required in large amounts.
    • Nitrogen (N): Essential for proteins and chlorophyll.
    • Phosphorus (P): Important for energy transfer (ATP).
    • Potassium (K): Regulates enzyme activity and water balance.
    • Calcium (Ca): Important for cell wall structure.
    • Magnesium (Mg): Central element in chlorophyll.
    • Sulfur (S): Component of amino acids and proteins.
      
      paragraph
33. Micronutrients: Needed in small amounts.
    • Iron (Fe): Helps in chlorophyll synthesis.
    • Zinc (Zn): Activates enzymes.
    • Copper (Cu): Aids in photosynthesis.
    • Manganese (Mn): Involved in splitting water during light reactions.
    • Boron (B): Important for cell wall strength.
      
      paragraph

Deficiency Symptoms of Key Nutrients

34. Nitrogen Deficiency:
    • Symptoms: Yellowing of leaves (chlorosis), stunted growth.
    • Role: Needed for chlorophyll and protein synthesis.
      
      paragraph
35. Phosphorus Deficiency:
    • Symptoms: Purple discoloration of leaves, poor root development.
    • Role: Important for ATP and DNA.
      
      paragraph
36. Potassium Deficiency:
    • Symptoms: Browning and curling of leaf edges, weak stems.
    • Role: Regulates water uptake and enzyme activity.
      
      paragraph

Photosynthesis in Plants: Key Insights

37. Primary Producers: Photosynthesis forms the base of most food chains.
38. Oxygen Production: Supplies oxygen for respiration in living organisms.
39. Carbon Fixation: Helps regulate atmospheric carbon dioxide levels.
40. Energy Storage: Glucose serves as an energy reserve for plants.
41. Growth Support: Provides energy for growth, repair, and reproduction.
    
    paragraph

Environmental Factors Affecting Photosynthesis

42. Light Intensity: Higher light intensity increases the rate of photosynthesis.
43. Carbon Dioxide Concentration: Higher $CO_2$ levels boost glucose production.
44. Temperature: Optimal temperatures enhance enzyme activity.
45. Water Availability: Necessary for splitting during the light reaction.
    
    paragraph

Chloroplasts and Their Role

46. Contain chlorophyll, which absorbs light.
47. Have thylakoids where light reactions occur.
48. Stroma is the site of the Calvin cycle.
    
    paragraph

Photosynthesis Experiments

49. Bubble Test: Submerged aquatic plants release bubbles of oxygen during photosynthesis.
50. Floating Leaf Disk Test: Leaf disks float as they produce oxygen.
    
    paragraph

Adaptive Mechanisms in Photosynthesis

51. C3 Plants: Perform standard photosynthesis.
52. C4 Plants: Adapted to hot environments; minimize water loss.
53. CAM Plants: Photosynthesize at night to conserve water.
    
    paragraph

Advanced Points on Nutrient Deficiency

54. Iron Deficiency: Causes yellowing of young leaves.
55. Magnesium Deficiency: Leads to interveinal chlorosis.
56. Boron Deficiency: Causes brittle leaves and hollow stems.
    
    paragraph

Importance of Photosynthesis in Agriculture

57. Boosts crop yield by enhancing photosynthesis efficiency.
58. Adequate nitrogen, phosphorus, and potassium improve plant health.
59. Protecting plants from nutrient deficiencies ensures better photosynthesis.
    
    paragraph

Summary of Processes

60. Light reaction captures energy.
61. Dark reaction synthesizes glucose.
62. Both reactions depend on enzymes.
    
    paragraph

Practical Applications

63. Greenhouses: Enhance photosynthesis with controlled light and $CO_2$.
64. Bioenergy: Plants produce biofuels through photosynthesis.
65. Reforestation: Improves carbon fixation.
    
    paragraph

Photosynthesis and Climate Change

66. Absorbs $CO_2$ from the atmosphere.
67. Reduces global warming by storing carbon in plants.
    
    paragraph

Economic Importance

68. Source of food, oxygen, and raw materials.
69. Basis for agriculture and forestry.
70. Drives ecosystems and biodiversity.
    paragraph

Jamb(UTME) tutorial on animal nutrition

Classes of Food Substances

1. Carbohydrates: Composed of carbon, hydrogen, and oxygen.
2. Proteins: Made of amino acids containing carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur.
3. Fats and Oils: Composed of glycerol and fatty acids.
4. Vitamins: Organic compounds required in small amounts.
5. Mineral Salts: Inorganic substances required in small amounts.
6. Water: Essential for life, makes up 60–70% of the human body.
   
   paragraph

Sources of Each Class of Food

7. Carbohydrates: Found in rice, bread, potatoes, and fruits.
8. Proteins: Found in meat, fish, eggs, beans, and lentils.
9. Fats and Oils: Found in butter, margarine, nuts, and avocado.
10. Vitamins: Found in fruits (e.g., vitamin C in oranges), vegetables (e.g., vitamin A in carrots), and dairy (e.g., vitamin D in milk).
11. Minerals: Found in leafy greens (e.g., calcium), seafood (e.g., iodine), and bananas (e.g., potassium).
12. Water: Found in drinks and watery foods like fruits and vegetables.
    
    paragraph

Importance and Deficiency of Food Classes

13. Carbohydrates: Provide energy; deficiency causes fatigue and low energy.
14. Proteins: Build and repair tissues; deficiency causes kwashiorkor and stunted growth.
15. Fats and Oils: Provide energy and insulation; deficiency leads to low energy reserves and poor insulation.
16. Vitamin A: Needed for vision; deficiency causes night blindness.
17. Vitamin C: Needed for healthy skin and gums; deficiency causes scurvy.
18. Vitamin D: Needed for bone health; deficiency causes rickets.
19. Iron: Essential for red blood cell formation; deficiency causes anemia.
20. Calcium: Strengthens bones and teeth; deficiency causes osteoporosis.
21. Water: Maintains hydration and regulates body temperature; deficiency causes dehydration.
    paragraph

Balanced Diet

22. A balanced diet contains appropriate proportions of carbohydrates, proteins, fats, vitamins, minerals, fiber, and water.
23. Importance: Maintains health, supports growth, and prevents diseases.
24. An imbalance can lead to malnutrition, obesity, or deficiency diseases.
    
    paragraph

Structure of a Typical Mammalian Tooth

25. Crown: The visible part above the gum.
26. Root: Embedded in the jawbone.
27. Enamel: Hard outer layer that protects the tooth.
28. Dentine: Lies beneath the enamel, supports the structure.
29. Pulp Cavity: Contains nerves and blood vessels.
30. Cementum: Covers the root and attaches the tooth to the jawbone.
    
    paragraph

Types of Mammalian Teeth and Their Functions

31. Incisors: Flat and sharp; used for cutting and biting food.
32. Canines: Pointed; used for tearing food.
33. Premolars: Broad and ridged; used for grinding and crushing food.
34. Molars: Larger and flatter; used for chewing and grinding food.
    paragraph

Comparison of Dental Formulae

35. Man: $\text{I: 2/2, C: 1/1, P: 2/2, M: 3/3}$, total 32 teeth.
36. Sheep: $\text{I: 0/4, C: 0/0, P: 3/3, M: 3/3}$, total 32 teeth.
37. Dog: $\text{I: 3/3, C: 1/1, P: 4/4, M: 2/3}$, total 42 teeth.
    
    paragraph

Components of the Alimentary Canal and Their Functions

38. Mouth: Chews and mixes food with saliva.
39. Esophagus: Transports food to the stomach.
40. Stomach: Secretes gastric juices for protein digestion.
41. Small Intestine: Absorbs nutrients via villi.
42. Large Intestine: Absorbs water and forms feces.
43. Rectum and Anus: Stores and expels waste.
    
    paragraph

Accessory Organs and Their Functions

44. Liver: Produces bile to emulsify fats.
45. Pancreas: Produces digestive enzymes and regulates blood sugar.
46. Gallbladder: Stores bile until needed for digestion.
    
    paragraph

Enzymes in Digestion

47. Carbohydrates:
    • Enzyme: Amylase.
    • Source: Salivary glands and pancreas.
    • Action: Breaks starch into maltose.
      
      paragraph
48. Proteins:
    • Enzyme: Pepsin.
    • Source: Stomach.
    • Action: Breaks proteins into peptides.
      
      paragraph
49. Fats:
    • Enzyme: Lipase.
    • Source: Pancreas.
    • Action: Breaks down fats into glycerol and fatty acids.
      
      paragraph

End Products of Food Digestion

50. Carbohydrates: Glucose.
51. Proteins: Amino acids.
52. Fats: Glycerol and fatty acids.
    
    paragraph

Deficiency Symptoms of Key Nutrients

53. Iron: Leads to fatigue and anemia.
54. Calcium: Causes weak bones and teeth.
55. Potassium: Results in muscle weakness.
56. Magnesium: Causes muscle cramps.
57. Zinc: Impairs wound healing.
    
    paragraph

Processes in Digestion

58. Mastication: Chewing food into smaller pieces.
59. Deglutition: Swallowing food.
60. Peristalsis: Wave-like movements that push food through the gut.
    
    paragraph

Functions of Digestive Juices

61. Saliva: Moistens food and contains amylase.
62. Gastric Juice: Contains pepsin and hydrochloric acid.
63. Bile: Neutralizes stomach acid and emulsifies fats.
64. Pancreatic Juice: Contains amylase, lipase, and proteases.
    
    paragraph

Structure-Function Relationships in the Alimentary Canal

65. Mouth: Teeth and tongue aid in mechanical digestion.
66. Esophagus: Smooth muscles enable peristalsis.
67. Stomach: Muscular walls churn food; glands produce enzymes and acid.
68. Small Intestine: Villi and microvilli increase surface area for absorption.
69. Large Intestine: Absorbs water; compact structure for fecal storage.
    
    paragraph

Nutritional Importance

70. Carbohydrates: Provide quick energy.
71. Proteins: Build muscles, enzymes, and hormones.
72. Fats: Store energy and cushion organs.
73. Vitamins: Regulate body functions.
74. Minerals: Strengthen bones and teeth, regulate fluids.
75. Water: Dissolves nutrients and removes waste.
    
    paragraph

Special Features in Animals

76. Sheep's Teeth: Lack upper incisors; adapted for grazing.
77. Dog's Canines: Strong and sharp for tearing meat.
78. Human Premolars: Flattened for grinding.
    
    paragraph

Balance in Diet

79. A balanced diet ensures physical and mental health.
80. Prevents lifestyle diseases like obesity and diabetes.
    
    paragraph

Importance of Enzymes

81. Speed up digestion by breaking down complex molecules.
82. Ensure nutrients are absorbed efficiently.
    
    paragraph

Specialized Structures

83. Liver Lobules: Process nutrients and detoxify.
84. Gallbladder: Stores and releases bile.
    
    paragraph

Additional Nutritional Disorders

85. Pellagra: Caused by vitamin B3 deficiency.
86. Beriberi: Caused by vitamin B1 deficiency.
87. Goiter: Caused by iodine deficiency.
    
    paragraph

Energy Transfer

88. Digestion converts food into energy.
89. ATP is the energy currency of cells.
    
    paragraph

Comparative Digestion

90. Herbivores have longer intestines for plant digestion.
91. Carnivores have shorter guts for protein digestion.
    
    paragraph

Absorption

92. Small intestine absorbs most nutrients.
93. Large intestine absorbs water and salts.
    
    paragraph

Key Enzymes

94. Trypsin: Digests proteins in the small intestine.
95. Maltase: Breaks maltose into glucose.
    
    paragraph

End Products of Food

96. Carbohydrates: Provide immediate energy.
97. Proteins: Repair and build tissues.
98. Fats: Long-term energy storage.
99. Balanced diets prevent deficiencies and maintain homeostasis.
100. Nutritional health is key to overall well-being.

I recommend you check my Post on the following: