Topic – 1.1
What is a characteristic of all living organisms?
A) breathing
B) egestion
C) excretion
D) ingestion
▶️ Answer/Explanation
Ans: C
Excretion (C) is a universal characteristic of life, as all organisms produce metabolic waste (e.g., CO2, urea) that must be removed.
Breathing (A) is limited to animals with respiratory systems, while ingestion (D) and egestion (B) apply primarily to heterotrophs. Plants and microbes also excrete, making C the correct choice.
Topic – 1.2
The diagram shows a flowering plant. A key can be used to identify the plant. Which letter in the key identifies the flowering plant shown in the diagram?
▶️ Answer/Explanation
Ans: D
To identify the plant using the key, we follow these steps:
- The flower in the diagram has five petals, so we follow the path labeled “flower has five petals” in the key.
- The leaves of the plant have jagged edges, not smooth edges.
- In the key, this combination (five petals + jagged edges) leads to the letter D.
Thus, the correct answer is D, as it matches the plant’s features.
Topic – 1.3
The drawing shows a ground squirrel. Which feature identifies this animal as a mammal?
A) eye
B) four limbs
C) fur
D) tail
▶️ Answer/Explanation
Ans: C
The defining characteristic of mammals is the presence of fur or hair (C). While other options like eyes (A), four limbs (B), or tails (D) are common in many animal groups, fur is unique to mammals.
Eyes are found in nearly all vertebrates and invertebrates, limbs are shared with reptiles/amphibians, and tails appear in birds/reptiles. Thus, the correct answer is C (Fur), as it is exclusive to mammals.
Topic – 2.1
The diagram shows different types of cell. Which structure do all these cells have?
A) cell membrane
B) cell wall
C) chloroplast
D) nucleus
▶️ Answer/Explanation
Ans: A
The cell membrane (A) is the only structure common to all cell types—plant, animal, and bacterial cells. It regulates the movement of substances in and out of the cell.
Cell walls (B) are absent in animal cells, chloroplasts (C) are exclusive to plant cells, and nuclei (D) are missing in prokaryotic cells like bacteria. Thus, the correct answer is A (Cell membrane).
Topic – 2.2
The drawing of the insect shown has a magnification of ×5. The scale shown is in mm. What is the actual size of the insect?
A) 25 mm
B) 120 mm
C) 130 mm
D) 625 mm
▶️ Answer/Explanation
Ans: A
The insect’s measured length in the diagram is approximately 125 mm. Since the magnification is ×5, the actual size is calculated using the formula:
\[ \text{Actual Size} = \frac{\text{Measured Size}}{\text{Magnification}} = \frac{125\ \text{mm}}{5} = 25\ \text{mm} \]
Thus, the correct answer is A (25 mm), as the other options do not match the calculated value.
Topic – 3.1
Which factor would increase the rate of diffusion of oxygen molecules out of a photosynthesizing leaf?
▶️ Answer/Explanation
Ans: B
The rate of diffusion is governed by Fick’s Law, which states:
\[ \text{Rate of Diffusion} \propto \frac{\text{Surface Area} \times \text{Concentration Gradient}}{\text{Distance}} \]
Thus, the rate increases when:
- The concentration gradient is steeper (A is incorrect).
- The distance for diffusion is shorter (B is correct).
- The surface area is larger (C is incorrect).
- The temperature is higher (D is incorrect, as it reduces kinetic energy).
Since option B directly reduces the diffusion distance, it is the correct answer.
Topic – 3.2
Which process only involves the movement of water through the partially permeable membrane of a cell?
A) absorption
B) evaporation
C) osmosis
D) transpiration
▶️ Answer/Explanation
Ans: C
Osmosis is the specific process where water molecules move across a partially permeable membrane from a region of higher water concentration to lower water concentration. This is distinct from absorption (A), which can involve other substances, evaporation (B), which is a phase change, and transpiration (D), which is water loss from leaves. Thus, the correct answer is C (Osmosis).
Topic – 3.3
Which statement about active transport is correct?
▶️ Answer/Explanation
Ans: C
Active transport moves particles against their concentration gradient (from low to high concentration) using energy from ATP. This distinguishes it from passive processes like diffusion or osmosis.
Why not the others?
- A: Incorrect – Active transport occurs across cell membranes.
- B: Incorrect – It requires energy (ATP).
- D: Incorrect – Water movement is osmosis, not active transport.
Topic – 4.1
DCPIP can be used to test for vitamin C in food. Lemon juice contains vitamin C. When lemon juice is tested with DCPIP what are the results?
▶️ Answer/Explanation
Ans: A
DCPIP is a blue dye that decolorizes when reduced by vitamin C. Since lemon juice contains vitamin C, it reduces DCPIP, causing the solution to change from blue to colorless.
The reaction occurs because vitamin C donates electrons to DCPIP, which is why the correct observation is A (starts blue, finishes colorless).
| Step | Observation |
|---|---|
| Start of test | DCPIP is blue |
| Add lemon juice | Blue color disappears (fades to colorless) |
| Final result | Colourless solution |
DCPIP (blue dye) is reduced by vitamin C (ascorbic acid), turning it from blue to colourless. Lemon juice contains vitamin C, so it causes this color change.
Topic – 4.1
Which reagent is used to test for the presence of protein in food?
▶️ Answer/Explanation
Ans: B
The Biuret test is specifically used to detect proteins. When Biuret solution is added to a food sample containing protein, the solution changes from blue to purple, indicating a positive result.
Other reagents test for different nutrients: Benedict’s solution (A) detects reducing sugars, ethanol (C) tests for lipids, and iodine solution (D) identifies starch. Thus, the correct answer is B (Biuret solution).
| Reagent | Tests for | Positive Result |
|---|---|---|
| Benedict’s solution | Reducing sugars | Blue → Brick-red (after heating) |
| Biuret solution | Protein | Blue → Purple |
| Ethanol | Lipids | White emulsion |
| Iodine solution | Starch | Yellow-brown → Blue-black |
Topic – 5.1
The graph shows the effect of pH on the rate of reaction of an enzyme. What does the graph show?
A) The enzyme is destroyed at pH 9.
B) The enzyme works best at pH 6.
C) The rate of reaction halves as the pH changes from pH 5 to pH 7.
D) The rate of reaction is the same at pH 5 and pH 8.5.
▶️ Answer/Explanation
Ans: D
The graph indicates that the enzyme’s rate of reaction is identical at pH 5 and pH 8.5, as the curve reaches the same height at these points. This matches option D.
Option A is incorrect because the graph does not show enzyme destruction at pH 9. Option B is unsupported unless the peak is at pH 6, which isn’t evident. Option C is invalid unless the rate halves precisely between pH 5 and 7, which isn’t confirmed. Thus, D is correct.
Topic – 6.1
The diagram shows an experiment to investigate the balance between respiration and photosynthesis. In which tube are photosynthesis and respiration taking place at the same time?
▶️ Answer/Explanation
Ans: C
Tube C is the correct answer because it contains pond weed exposed to light, enabling photosynthesis, while respiration occurs simultaneously in the plant cells.
Tube A (snail + pond weed in darkness) and Tube B (pond weed in darkness) only show respiration. Tube D (snail in light) lacks photosynthesis. Thus, only C demonstrates both processes.
Key Reasoning: Photosynthesis requires light, while respiration occurs continuously in living cells. Tube C meets both conditions.
Topic – 6.1
Some variegated leaves have white parts and green parts. A plant with variegated leaves has the starch removed from its leaves by placing it in a dark cupboard for 48 hours. Black paper is then fixed on one leaf as shown and the plant is exposed to light. After 24 hours, which part of the leaf contains starch?
▶️ Answer/Explanation
Ans: D
The experiment involves destarching the leaves (removing stored starch) by keeping the plant in the dark for 48 hours. After exposing it to light for 24 hours with black paper covering part of the leaf:
- Green parts (exposed to light): Contain chlorophyll and perform photosynthesis, producing starch (e.g., part D).
- White parts: Lack chlorophyll, so no starch is produced even with light.
- Covered parts (black paper): No light = no photosynthesis, so no starch.
Thus, only the green, uncovered area (D) contains starch after the experiment.
Topic – 6.2
The diagram shows a plant cell. Which type of cell is shown?
A) cuticle cell
B) epidermal cell
C) palisade mesophyll cell
D) spongy mesophyll cell
▶️ Answer/Explanation
Ans: C
The diagram depicts a palisade mesophyll cell (C), identifiable by its dense arrangement of chloroplasts, which maximize photosynthesis. These cells are located just below the epidermis in leaves.
Why not others? Cuticle (A) is a waxy layer, not a cell. Epidermal cells (B) lack abundant chloroplasts. Spongy mesophyll (D) has loosely packed chloroplasts for gas exchange, not primary photosynthesis.
Topic – 7.1
The pie charts show the composition of 100 g of four different foods. Which food provides the most energy?
▶️ Answer/Explanation
Ans: B
Energy is primarily derived from fats (highest energy/gram), followed by carbohydrates and proteins. Water contributes no energy.
Food B has the lowest water content and a balanced distribution of fats, carbohydrates, and proteins, maximizing energy per 100 g. In contrast, Foods C and D have high water content, diluting their energy density despite some fat content.
Thus, B provides the most energy.
Topic – 7.2
The diagram shows the digestive system and some of its associated organs. Which label identifies the liver?
▶️ Answer/Explanation
Ans: A
The liver is located in the upper right abdomen, below the diaphragm and to the right of the stomach. In the diagram, Label A correctly identifies the liver due to its:
- Position (upper right quadrant)
- Large, lobed structure
- Proximity to the stomach (Label B) and gallbladder (if visible)
Why other labels are incorrect:
– B: Likely the stomach (J-shaped, below the liver).
– C: Small intestine (coiled structure, lower abdomen).
– D: Possibly the pancreas (smaller, behind the stomach).
Topic – 7.3
Which statements about teeth are correct?
1. Canine teeth are for chewing and grinding food.
2. Incisor teeth are for biting and cutting food.
3. Premolar teeth are for chewing and grinding food.
▶️ Answer/Explanation
Ans: B
Analysis of each statement:
- Canine teeth are pointed and sharp, designed for tearing food (not chewing/grinding). Thus, statement 1 is incorrect.
- Incisor teeth are flat and chisel-shaped, specialized for biting and cutting food. Statement 2 is correct.
- Premolar teeth have broad surfaces for chewing and grinding food. Statement 3 is correct.
Since only statements 2 and 3 are accurate, the correct answer is B (2 and 3 only).
Topic – 7.4
What is the definition of chemical digestion?
A) Large insoluble molecules are changed into smaller soluble molecules.
B) Large soluble molecules are changed into smaller soluble molecules.
C) Small insoluble molecules and ions are passed through the wall of the small intestine.
D) Small soluble molecules and ions are passed through the wall of the small intestine.
▶️ Answer/Explanation
Ans: A
Chemical digestion involves the breakdown of large, insoluble molecules (e.g., starch, proteins) into smaller, soluble molecules (e.g., glucose, amino acids) through enzymatic action. This process enables nutrient absorption. Option A correctly describes this, while B refers to soluble molecules (incorrect), and C/D describe absorption, not digestion.
Topic – 7.4
In which part of the alimentary canal does hydrochloric acid provide an acid pH for enzymes?
▶️ Answer/Explanation
Ans: D
Hydrochloric acid (HCl) is secreted by the stomach walls, creating an acidic environment (pH 1.5–3) for the enzyme pepsin to digest proteins effectively.
Why not the others?
- A (Colon): Absorbs water; no acidic pH.
- B (Duodenum): Receives alkaline bile/pancreatic juice.
- C (Ileum): Neutral pH for nutrient absorption.
Thus, the correct answer is D (Stomach).
Topic – 8.1
Which tissue has the function of providing support for a plant?
▶️ Answer/Explanation
Ans: D
Xylem is the correct answer because it provides structural support to the plant. Its thick, lignified cell walls help maintain the plant’s rigidity and prevent it from collapsing.
Why not the others?
- A) Epidermis – Protects the plant but does not provide structural support.
- B) Mesophyll – Involved in photosynthesis, not support.
- C) Phloem – Transports sugars but lacks the rigid structure needed for support.
Thus, xylem (D) is the tissue responsible for plant support.
▶️ Answer/Explanation
Ans: A
Increasing wind speed enhances the rate of transpiration by removing the moist air around the stomata, creating a steeper water vapor gradient. This causes more water to evaporate from the leaf surface.
Graph A correctly depicts this relationship, showing a steady rise in transpiration rate as wind speed increases. The other graphs either show no effect (B/C) or a decrease (D), which contradicts biological principles.
Topic – 9.2
What ensures one-way flow of blood in the circulatory system?
A) atria
B) septum
C) valves
D) ventricles
▶️ Answer/Explanation
Ans: C
Valves are specialized structures in the heart and veins that ensure blood flows in one direction and prevent backflow. They include:
- Tricuspid and bicuspid/mitral valves (between atria and ventricles)
- Pulmonary and aortic valves (at heart exits)
- Vein valves (in peripheral veins)
Why other options are incorrect:
A) Atria receive blood but lack mechanisms to enforce one-way flow.
B) Septum separates heart chambers but does not regulate flow direction.
D) Ventricles pump blood but rely on valves to prevent backflow.
Topic – 9.3
The diagrams show sections through three blood vessels, which are not drawn to the same scale. Some red blood cells are shown in vessel 3. In which order will red blood cells flow through these vessels when travelling from the right ventricle to the left atrium of the heart?
A) 1 → 2 → 3
B) 1 → 3 → 2
C) 2 → 3 → 1
D) 3 → 1 → 2
▶️ Answer/Explanation
Ans: B (1 → 3 → 2)
The correct sequence follows the pulmonary circulation pathway:
- Vessel 1: Pulmonary artery (carries deoxygenated blood from right ventricle to lungs)
- Vessel 3: Capillaries (site of gas exchange where RBCs become oxygenated)
- Vessel 2: Pulmonary vein (returns oxygenated blood to left atrium)
Key points: The presence of RBCs in vessel 3 confirms it as capillaries, while vessel 1’s thick wall indicates an artery. Vessel 2’s thin wall matches vein characteristics.
Topic – 9.2
Scientists used an ECG trace to monitor the heart of a student at rest and during exercise. What is the explanation for the difference in the ECG traces?
A) During exercise the heart rate increases to transport more oxygen to muscles.
B) During exercise the heart rate increases to breathe in more oxygen.
C) During exercise the breathing rate increases to supply more oxygen to muscles.
D) During exercise the breathing rate increases to breathe in more oxygen.
▶️ Answer/Explanation
Ans: A
The ECG trace shows a faster heart rate during exercise because:
- Muscles need more oxygen for aerobic respiration to produce energy.
- The heart beats faster to pump more oxygen-rich blood to the muscles.
- This is reflected in the ECG as more peaks (heartbeats) in the same time period.
Option A correctly links the increased heart rate to oxygen transport, while other options confuse heart function with breathing or are irrelevant to ECG changes.
Topic – 10.1
Statements about pathogens are given.
1. A pathogen is a disease-causing organism.
2. All pathogens are bacteria.
3. A pathogen can be transmitted by indirect contact through contaminated food.
Which statements are correct?
A) 1 and 2
B) 1 and 3
C) 1 only
D) 3 only
▶️ Answer/Explanation
Ans: B
Statement 1 is correct: Pathogens include all disease-causing agents (bacteria, viruses, fungi, etc.).
Statement 2 is incorrect: Viruses (like influenza) and fungi (like athlete’s foot) are non-bacterial pathogens.
Statement 3 is correct: Foodborne illnesses (e.g., salmonella) demonstrate indirect transmission.
Thus, 1 and 3 (Option B) are the correct statements about pathogens.
Topic – 11.1
Which structure in the breathing system has the thinnest wall?
A) alveolus
B) bronchiole
C) bronchus
D) trachea
▶️ Answer/Explanation
Ans: A
The alveolus (A) has the thinnest wall in the breathing system, consisting of just one layer of epithelial cells. This ultra-thin structure maximizes gas exchange efficiency (O2 and CO2 diffusion) between the lungs and bloodstream.
Other structures are thicker: Bronchioles (B) lack cartilage but have muscle layers, Bronchi (C) and Trachea (D) contain cartilage rings for structural support.
Topic – 12.2
What are the products of aerobic respiration?
A) carbon dioxide and lactic acid
B) carbon dioxide and water
C) carbon dioxide only
D) lactic acid and water
▶️ Answer/Explanation
Ans: B
Aerobic respiration fully oxidizes glucose (C6H12O6) using oxygen (O2), producing:
- Carbon dioxide (CO2) – Released as a waste product.
- Water (H2O) – Formed when oxygen accepts electrons and hydrogen ions.
The balanced equation is:
\[ C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{Energy (ATP)} \]
Why other options are incorrect:
– A: Lactic acid is produced in anaerobic respiration (e.g., in muscles during intense exercise).
– C: Omits water, a key byproduct.
– D: Combines incorrect products (lactic acid is anaerobic; water alone is insufficient).
Topic – 12.3
What are the products of anaerobic respiration in yeast?
▶️ Answer/Explanation
Ans: A
Anaerobic respiration in yeast (fermentation) produces:
- Ethanol (alcohol) – The main product of fermentation.
- Carbon dioxide (CO₂) – Responsible for bubbles in bread and beer.
- No lactic acid – Unlike in animal cells, yeast does not produce lactic acid.
The chemical equation for this process is:
\[ \text{C}_6\text{H}_{12}\text{O}_6 \rightarrow 2\text{C}_2\text{H}_5\text{OH} + 2\text{CO}_2 + \text{Energy (ATP)} \]
Why other options are incorrect:
- B: Yeast produces CO₂, and no lactic acid.
- C: Alcohol is always produced in yeast fermentation.
- D: Neither condition matches yeast fermentation.
Thus, the correct answer is A (alcohol, carbon dioxide, no lactic acid).
Topic – 13.1
Some excretory products are listed.
1 carbon dioxide
2 excess ions
3 excess water
4 urea
Which products are excreted by the kidneys?
A) 1, 2 and 3
B) 2, 3 and 4
C) 1 and 2 only
D) 3 and 4 only
▶️ Answer/Explanation
Ans: B
The kidneys excrete three main waste products:
- Excess ions (e.g., sodium, potassium) through urine
- Excess water to maintain fluid balance
- Urea, the nitrogenous waste from protein metabolism
Carbon dioxide (1) is excreted by the lungs, not kidneys. Therefore, the correct combination is 2, 3 and 4 (Option B).
Topic – 14.1
A person touches a sharp object. The person immediately pulls their hand away.
Which row shows the correct description of the term?
▶️ Answer/Explanation
Ans: D
The stimulus is the sharp object touching the skin, which initiates the reflex action. This is the only correctly matched pair among the options.
Why not the others?
- A: Incorrect – The effector is the muscles (not the action of pulling).
- B: Incorrect – Receptors are in the skin, not muscles.
- C: Incorrect – The response is the action (pulling away), not the neurons.
Key Terms in Reflex Arc:
- Stimulus: Sharp object (D is correct).
- Receptor: Sensory neurons in skin.
- Effector: Arm muscles.
- Response: Hand withdrawal.
Topic – 14.2
Which structure focuses light on the retina?
▶️ Answer/Explanation
Ans: C
The lens is responsible for fine-tuning and focusing light precisely onto the retina. This process is called accommodation, where the lens changes shape to focus on objects at different distances.
Why not the others?
- A) Cornea – While it bends light initially, it doesn’t adjust focus like the lens.
- B) Iris – Controls pupil size to regulate light entry but doesn’t focus light.
- D) Optic nerve – Transmits visual signals to the brain but plays no role in focusing.
The lens’s ability to change curvature makes it uniquely suited for focusing light onto the retina, making C (lens) the correct answer.
Topic – 14.3
Which statements describe adrenaline and its effects on the human body?
1 Pupil diameter becomes smaller.
2 Breathing rate decreases.
3 Heart rate increases.
4 Adrenaline is transported in the blood.
▶️ Answer/Explanation
Ans: D
Adrenaline triggers the “fight or flight” response, causing:
- Pupil dilation (not constriction – statement 1 is wrong)
- Increased breathing rate (not decreased – statement 2 is wrong)
- Increased heart rate (statement 3 is correct)
- Transport via bloodstream (statement 4 is correct)
Only statements 3 and 4 are accurate, making D the correct choice.
Topic – 15.1
Which statements about drugs are correct?
- Drugs affect or modify chemical reactions in the body.
- Drugs called antibiotics can be used to kill bacteria.
- Drugs called antibiotics can be used to kill viruses.
A) 1 and 2
B) 2 and 3
C) 1 only
D) 2 only
▶️ Answer/Explanation
Ans: A
Analysis of each statement:
- Correct: Drugs alter biochemical processes (e.g., painkillers block pain signals, antibiotics disrupt bacterial metabolism).
- Correct: Antibiotics specifically target bacteria (e.g., penicillin inhibits bacterial cell wall synthesis).
- Incorrect: Antibiotics are ineffective against viruses; antivirals or vaccines are required for viral infections.
Thus, only statements 1 and 2 are correct, making A the right choice.
▶️ Answer/Explanation
Ans: C
Fertilisation occurs when sperm and egg fuse to form a zygote. The diagram shows:
- Point A: Egg production (oogenesis)
- Point B: Sperm production (spermatogenesis)
- Point C: Fusion of gametes (fertilisation)
- Point D: Embryo development (post-fertilisation)
Since fertilisation specifically refers to the fusion of gametes, Point C is the correct answer. This is the only stage where both haploid gametes combine to form a diploid zygote.
Topic – 17.4
The seed shape of peas can be smooth or wrinkled. The allele for smooth is dominant and the allele for wrinkled is recessive. Two heterozygous plants are crossed. What is the expected percentage of offspring with a smooth shape?
A) 0%
B) 50%
C) 75%
D) 100%
▶️ Answer/Explanation
Ans: C
To solve this monohybrid cross:
- Let S = smooth (dominant) and s = wrinkled (recessive).
- Heterozygous parents both have genotype Ss.
- A Punnett square shows possible offspring:
- SS (25%) – smooth
- Ss (50%) – smooth
- ss (25%) – wrinkled
Total smooth offspring = 25% (SS) + 50% (Ss) = 75%.
Topic – 18.1
Which human phenotype is caused by genes only?
A) ABO blood group
B) body mass
C) foot size
D) height
▶️ Answer/Explanation
Ans: A
ABO blood group (A) is the only phenotype entirely determined by genes (IA, IB, i alleles). Environmental factors cannot alter inherited blood type.
Other options involve gene-environment interactions:
• Body mass (B): Affected by diet/exercise
• Foot size (C): Influenced by nutrition
• Height (D): Modified by childhood health
Thus, A is correct as it represents pure monohybrid inheritance without environmental influence.
Topic – 19.1
What is a correct ecological definition?
A) A community is a group of organisms of one species living in the same area.
B) An ecosystem is a community of organisms and their environment interacting together.
C) A population is a group of different species living together.
D) A species is all of the different organisms living in a community.
▶️ Answer/Explanation
Ans: B
Ecosystem (B) is correctly defined as a biological community interacting with its physical environment. This is the only accurate definition among the options.
Why others are incorrect:
– A: Community includes multiple species, not just one.
– C: Population refers to one species, not multiple.
– D: Species refers to organisms that can interbreed, not all organisms in a community.
Topic – 20.4
Which action will decrease the population of an endangered animal species in a habitat?
A) a ban on hunting this species
B) building homes for people in this area
C) educating people about this species
D) using captive breeding programmes to release animals of this species into the habitat
▶️ Answer/Explanation
Ans: B
Building homes for people in this area (B) would decrease the population because:
- It leads to habitat destruction, reducing living space and resources.
- Increases human-wildlife conflicts and pollution.
Why other options would increase populations:
– A: Hunting bans protect species from direct harm.
– C: Education promotes conservation efforts.
– D: Captive breeding directly boosts population numbers.
Thus, B is the only option that clearly threatens the species’ survival through habitat loss.
▶️ Answer/Explanation
Ans: D
Key reasons bacteria are used in genetic modification:
- Rapid reproduction – Bacteria divide quickly (every 20-30 minutes) through binary fission, allowing fast production of modified organisms.
- Simple DNA structure – Their single circular chromosome and plasmids make genetic manipulation easier compared to complex eukaryotic cells.
Why other options are incorrect:
- A: Bacteria have simple DNA, not complex.
- B: Bacteria reproduce quickly, not slowly.
- C: Bacteria are easy to manipulate, not difficult.
The correct combination is D (quick reproduction and simple DNA), as these are the primary advantages of using bacteria in genetic engineering.
Topic – 21.3
Which row shows uses of genetic modification?
▶️ Answer/Explanation
Ans: D
Genetic modification involves directly altering an organism’s DNA. The correct pair is:
- Producing insulin – Genetically modified bacteria produce human insulin
- Creating pest-resistant crops – Genes from bacteria are inserted into plants
Other options mix genetic modification with traditional methods (selective breeding, cross-pollination) which don’t involve direct DNA manipulation.