BZYET-143 Insect Vectors and Vector Borne Diseases is the elective Zoology theory course of the IGNOU Bachelor of Science (General), BSCG, that studies the insects which carry human disease and how to control them.
BZYET-143 Insect Vectors and Vector Borne Diseases key facts, June 2026
- Course code: BZYET-143
- Course title: Insect Vectors and Vector Borne Diseases
- Programme: Bachelor of Science (General), BSCG, with Zoology
- Credits: 4 (theory); companion lab BZYEL-144 is a separate 2-credit course
- Blocks and units: 4 blocks in 2 volumes; Units 10, 11, 13 and 15 confirmed on eGyanKosh, 15 units in all [VERIFY]
- Maximum marks: 50 (term-end exam)
- Duration: 2 hours
- Questions in the paper: 7 (Q1 compulsory, then any 4 of Q2 to Q7)
- Marks split: Q1 5×1 + 5×1; Q2 4×2.5; Q3 to Q6 10 each; Q7 2×5. 70 marks printed, 50 attempted
- Printed word limit: none; about 250 to 300 words for a 10-mark answer, worked out from the time available
- Assignment weightage: 30 per cent (one tutor-marked assignment a year)
- Sample answers on this page: 2 (Q3 and Q5)
- Questions in the paid file: All 7, including the 5 not answered on this page
What the BZYET-143 Solved Question Paper June 2026 covers
BZYET-143 Solved Question Paper June 2026 gives you complete answers to every question IGNOU set on 2 hours and 50 marks this June. The paper moves from tiny one-mark items, such as chloride cells and Attractive Toxic Sugar Baits, to full 10-mark answers on Aedes, IVM, houseflies and human lice.
This June paper leaned heavily on control. ATSBs, Wolbachia, ITNs and LLINs, IVM and the genetic control of Anopheles all appear in one sitting, so a student who only memorised insect anatomy would have lost marks. Our answers treat each control tool the way the course blocks present it.
On this page you can read two answers in full, Q3 and Q5, and see the exact text of the other five questions. Those five are answered only in the paid file, which you get on WhatsApp.
7 questions × 10 marks = 70 marks printed. You write Q1 + any 4 of Q2 to Q7 = 5 × 10 = 50 marks, so 2 of the 6 optional questions can be skipped. 120 minutes ÷ 5 answers = 24 minutes per question on average.
BZYET-143 sample solved questions: Aedes and housefly answers in full
Two of the seven June 2026 questions, Q3 on the Aedes mosquito and Q5 on houseflies, are answered below in full. They are written for revision, so each carries more points than a 10-mark answer needs in the exam hall.
Both are among the most repeated themes in this course, so they show you how the rest of the file is written. Question numbers and wording are copied from the official BZYET-143 paper.
Asked in 5 of 8 earlier papers Block 3 10 marks
Question 3 (10 marks)
3. Explain the life cycle of Aedes mosquito and the various ways it transmits the dengue virus. Add [a] note on the various methods of Aedes control. 10
Answer:
Introduction
Aedes aegypti, the yellow fever mosquito, is the main vector of dengue in Indian towns and cities, with Aedes albopictus, the Asian tiger mosquito, as a secondary vector in peri-urban and rural areas. Dengue is caused by the dengue virus (DENV), a flavivirus with four serotypes, DENV-1 to DENV-4. Only the female mosquito transmits it, because only she takes blood.
Life cycle of Aedes
Aedes shows complete metamorphosis (holometabolous development) with four stages: egg, larva, pupa and adult. In warm weather the whole cycle from egg to adult takes about 8 to 10 days, which is why case numbers rise sharply in and after the monsoon.
- Egg: the female lays eggs singly, not in rafts, on the damp inner walls of containers just above the waterline: coolers, tyres, flower pots, overhead tanks and discarded cups. Eggs are black, cigar-shaped and have no floats. They can survive drying for several months and hatch when rain or refilling floods them.
- Larva (wriggler): passes through four instars in about 5 to 7 days. It has a short, stout siphon with a single pair of hair tufts and hangs at an angle to the water surface. It feeds on bacteria, algae and organic debris.
- Pupa (tumbler): comma-shaped, active but non-feeding, breathes through a pair of respiratory trumpets and lasts about 2 to 3 days before the adult emerges.
- Adult: a small black mosquito with white bands on the legs. Ae. aegypti carries a lyre-shaped silvery pattern on the thorax, while Ae. albopictus has a single median white stripe. Adults bite by day, with peaks in the early morning and late afternoon, prefer human blood and rest indoors in dark corners. Each egg batch needs a blood meal.
Exam tip: draw a labelled cycle showing egg on a container wall, larva hanging at an angle, comma-shaped pupa and the adult with a striped thorax. It earns marks quickly.
Ways in which Aedes transmits the dengue virus
- Biological (propagative) transmission, human to mosquito to human: a female bites a person during the viraemic phase, roughly from a day before fever to about five days after. The virus multiplies in the midgut, spreads through the haemolymph and reaches the salivary glands. This extrinsic incubation period is about 8 to 12 days and shortens at higher temperatures. The mosquito then stays infective for life and injects virus with saliva at every bite.
- Multiple feeding in one cycle: Ae. aegypti is a nervous feeder. When disturbed it flies off and bites another person, so one infective female can infect several members of a household. This explains the typical clustering of dengue cases in one building or lane.
- Vertical (transovarial) transmission: an infected female can pass the virus into her eggs. Larvae and adults that develop from them are infected without ever biting a patient, which helps the virus survive dry seasons and gaps between outbreaks.
- Venereal transmission: males infected through the egg can pass the virus to females during mating. It occurs at low rates but adds to virus maintenance in nature.
After an infective bite, the intrinsic incubation period in humans is usually 4 to 7 days (range 3 to 14) before fever, headache, pain behind the eyes, joint and muscle pain and rash appear.
Methods of Aedes control
- Source reduction: the most effective step. Empty, scrub and dry coolers, tanks and pots once a week (the "dry day" promoted in India), cover stored water and dispose of tyres and junk that collect rainwater.
- Chemical larvicides: temephos at 1 ppm in containers that cannot be emptied; insect growth regulators such as pyriproxyfen and diflubenzuron stop adult emergence.
- Biological control: larvivorous fish such as Gambusia affinis and guppies (Poecilia reticulata) in wells and large tanks; the bacterial larvicide Bacillus thuringiensis israelensis (Bti); predatory copepods in some programmes.
- Adult control: space spraying or thermal fogging with pyrethrum extract or malathion during outbreaks to cut down infective females quickly.
- Personal protection: repellents such as DEET, full-sleeved clothing, window and door screens, and bed nets for anyone who sleeps by day, including infants and patients.
- Newer methods: release of Wolbachia-carrying mosquitoes that block virus replication, the sterile insect technique and self-limiting genetically modified strains.
- Surveillance and community action: larval indices such as the House, Container and Breteau indices guide action, while health education and municipal bye-laws push households to remove breeding sites.
Conclusion
Because Aedes breeds in clean water inside and around homes and bites by day, no single tool controls it. Weekly source reduction backed by larvicides, biological agents and community participation gives the most lasting protection against dengue.
Hall length: this answer runs to about 850 words, roughly three times what 27 minutes of writing allows. If time is short, keep the four stages with one labelled diagram, transmission points 1 and 3, source reduction, larvicides and biological control, and the two-line conclusion.
Asked in 6 of 8 earlier papers Block 4 10 marks
Question 5 (10 marks)
5. Give an account of diseases spread by houseflies, the ways of transmission and their control measures. 10
Answer:
Introduction
The housefly, Musca domestica (order Diptera, family Muscidae), is a non-biting fly with sponging mouthparts. It breeds in manure, garbage, night soil and rotting organic matter, then visits human food and faces. It is a mechanical vector: pathogens are carried on or through its body without multiplying or developing in it. Over 100 kinds of pathogens have been recovered from houseflies.
Diseases spread by houseflies
| Group | Disease and causative agent |
|---|---|
| Bacterial | Typhoid and paratyphoid (Salmonella Typhi, Paratyphi), cholera (Vibrio cholerae), bacillary dysentery (Shigella), infant diarrhoea and gastroenteritis (Escherichia coli), food poisoning (Salmonella) |
| Protozoal | Amoebic dysentery (Entamoeba histolytica cysts), giardiasis (Giardia cysts) |
| Viral | Hepatitis A and poliomyelitis (viruses recovered from flies) |
| Eye and skin | Trachoma and conjunctivitis (eye-seeking flies such as Musca sorbens), yaws (Treponema pertenue) |
| Helminthic | Eggs of roundworm (Ascaris), whipworm (Trichuris), pinworm (Enterobius) and tapeworms (Taenia) |
| Myiasis | Housefly larvae can occasionally cause accidental intestinal or wound myiasis |
Ways of transmission
- Body surface and legs: the body and legs are covered with bristles, and each foot has sticky, hairy pads (pulvilli). Pathogens from faeces, sputum and pus stick to them and are rubbed off on food, utensils and the eyes of children.
- Vomit drop: the fly cannot chew, so it regurgitates the contents of its crop onto solid food to dissolve it before sponging it up. This vomit drop, picked up from filth minutes earlier, contaminates the food.
- Faecal deposits: many bacteria, cysts and eggs survive passage through the fly gut. The fly defecates frequently while feeding, leaving dark "fly specks" full of pathogens.
- Habit of alternating: it moves freely between latrines, garbage and kitchens, which links filth directly to food and drink.
Rapid breeding adds to the risk. Eggs hatch in under a day, larvae grow for about 4 to 7 days and pupae take another 3 to 6, so a new generation appears in roughly 7 to 10 days in summer and the rainy season, when diarrhoeal diseases also peak.
Control measures
- Environmental sanitation (most important): store refuse in bins with tight lids, collect it daily and dispose of it by sanitary landfill, composting or incineration; build and use sanitary latrines; clear manure from cattle sheds at least twice a week so larvae cannot complete development.
- Mechanical methods: wire-mesh screens on doors and windows, food covers, sticky fly papers, baited fly traps and ultraviolet electrocuting traps in kitchens, hospitals and food shops.
- Chemical methods: residual sprays of pyrethroids (deltamethrin, cypermethrin) or organophosphates (malathion) on resting surfaces; space sprays of pyrethrum for quick knockdown; sugar baits mixed with insecticide; larvicides on breeding sites. Rotate chemicals, as houseflies develop resistance quickly.
- Biological methods: parasitoid wasps such as Spalangia and Muscidifurax that kill fly pupae, the fungus Beauveria bassiana, and predatory mites and beetles in manure.
- Health education: cover cooked food, wash hands with soap after using the toilet and before eating, and wash raw fruit and vegetables.
Conclusion
Since the housefly is only a mechanical carrier, breaking the link between filth and food through sanitation controls it best. Insecticides used alone give short relief and lead to resistance.
Hall length: this answer runs to about 650 words for revision. If time is short, keep the mechanical-vector definition, the five disease groups as a short list, transmission points 1 to 3, sanitation, screens and chemical methods, and the conclusion.
Questions answered only in the full file
The 5 questions below are printed exactly as they appear in the June 2026 paper. Their answers are not shown on this page.
1. (a) State one function of each of the following: 5×1=5
(i) Chloride cells
(ii) Hemocytes
(iii) Air sacs
(iv) Halteres
(v) ATSBs (Attractive Toxic Sugar Baits)
(b) Match the items given in column 'A' with column 'B': 5×1=5
| Column–A | Column–B |
|---|---|
| (i) Tegmina | (a) Microbial Control |
| (ii) Raptorial leg | (b) Cicadas |
| (iii) Glial cells | (c) Grasshopper |
| (iv) Wolbachia | (d) Mantis |
| (v) Tymbal organ | (e) Central nervous system |
2. Differentiate between the following pairs of terms: 4×2.5=10
(a) Insecticide Treated Nets (ITNs) and Long Lasting Insecticides [Insecticidal] Nets (LLINs)
(b) Hemimetabolous and Holometobolous [Holometabolous] Development
(c) Vector and Carrier
(d) Elytra and Tegmina
4. Describe the mechanical and biological control measures employed in Integrated Vector Management (IVM). 10
6. Explain the medical importance of three types of lice that are ectoparasitic on humans. 10
7. Write short notes on any two of the following: 2×5=10
(a) Structure of compound eye
(b) Chagas disease
(c) Vectorial capacity
(d) Genetic control of Anopheles
Q1 mixes body structures with modern control terms like ATSBs and Wolbachia, and Q7 gives a choice between the compound eye, Chagas disease, vectorial capacity and genetic control of Anopheles. Picking the right two notes is where many students gain or lose easy marks.
BZYET-143 Insect Vectors and Vector Borne Diseases block wise syllabus
The course is split into four blocks across two volumes: insect basics, non-dipteran vectors, mosquitoes, and other flies with Integrated Vector Management.
| Block | Block title | Units | Key topics |
|---|---|---|---|
| Block 1 | Introduction to Insects | [VERIFY: unit numbers] | Classification of class Insecta up to orders; modifications of mouthparts, antennae, wings and legs; haemolymph, tracheal system and compound eye |
| Block 2 | Medically Important Insect Vectors-I | [VERIFY: unit numbers] | Non-dipteran vectors: head, body and pubic lice; bed bugs and triatomine (reduviid) bugs; rat flea and plague |
| Block 3 | Medically Important Insect Vectors-II | Units 10 to 12 | Unit 10 Anopheles and malaria; Unit 11 Culex, filariasis and Japanese Encephalitis; Aedes, dengue and chikungunya [VERIFY: Unit 12 title] |
| Block 4 | Medically Important Insect Vectors-III and IVM | Units 13 to 15 | Unit 13 sand flies and kala-azar; houseflies and myiasis [VERIFY: Unit 14 title]; Unit 15 Integrated Vector Management (IVM) |
Volume 1, Insects: Introduction and Disease Vectors, holds Blocks 1 and 2, and Volume 2, Medically Important Dipterans and IVM, holds Blocks 3 and 4. You can open the official unit PDFs on the IGNOU eGyanKosh page for this course.
Block 4 carries the heaviest weight in recent papers, because IVM and houseflies return almost every year. If you are short of time, read our BZYET-143 Study Material notes for Blocks 3 and 4 first, then go back to anatomy in Block 1 for the one-mark items.
BZYET-143 question paper pattern and marks distribution
The BZYET-143 Question Paper has 7 questions for 50 marks in 2 hours: Q1 is compulsory, and you answer any four of Q2 to Q7.
| Question | Status | What it asks | Marks |
|---|---|---|---|
| Q1 | Compulsory | (a) five one-line functions, (b) five match-the-column pairs | 5×1 + 5×1 = 10 |
| Q2 | Optional (any 4 of Q2 to Q7) | Four differences between paired terms | 4×2.5 = 10 |
| Q3 | Optional | Long answer on Aedes life cycle, dengue transmission and control | 10 |
| Q4 | Optional | Long answer on mechanical and biological measures in IVM | 10 |
| Q5 | Optional | Long answer on housefly-borne diseases, transmission and control | 10 |
| Q6 | Optional | Long answer on the medical importance of three human lice | 10 |
| Q7 | Optional | Two short notes chosen from four options | 2×5 = 10 |
The IGNOU BZYET-143 Question Paper keeps a steady shape: one compulsory objective question, one differences question, a short-notes question and four long answers. Many long questions are split into 5 plus 5 or 6 plus 4 parts, as in December 2025, so read the marks printed beside each part.
Students who also sit other Zoology and Botany electives can compare this layout with the BSCG Question Paper collection, as most School of Sciences elective papers follow the same 2-hour, 50-mark design.
Choice rule: Q1 is fixed, and any 4 of the 6 optional questions gives 15 legal combinations. Only four optional answers count, so a fifth one earns nothing and costs you about 27 minutes.
How much to write. The paper prints no word limit, so the length below is worked out from time. A student writing by hand keeps up about 11 to 12 words a minute over a 2-hour paper.
| Marks | Where it appears | Minutes | Words |
|---|---|---|---|
| 1 | Q1, each of ten items | About 1 | One line, 10 to 15 words |
| 2.5 | Q2, each of four differences | About 7 | 70 to 80 words, or a short comparison table |
| 5 | Q7, each of two notes | About 13 to 14 | 130 to 150 words |
| 10 | Q3 to Q6 | About 27 | 250 to 300 words plus one labelled diagram |
120 minutes − about 10 for Q1 = 110 ÷ 4 = 27.5 minutes per optional question. Take 4 to 5 minutes for a diagram, leaving about 23 minutes of writing × 11.5 words a minute ≈ 265 words, roughly 26 words per mark.
Q1 earns 10 marks in about 10 minutes, 1 mark a minute. A long answer earns 10 marks in 27.5 minutes, about 0.36 a minute. Q1 turns time into marks nearly three times faster, so bank it first and do not linger on an item you cannot recall.
Most repeated BZYET-143 topics in official IGNOU papers
Human lice, metamorphosis and sand flies each appeared in 7 of the last 8 official BZYET-143 papers, and IVM, houseflies, vector concepts, wings, compound eye and haemolymph in 6.
| Topic | Sessions where it appeared | Papers (of 8) | June 2026 position |
|---|---|---|---|
| Human lice (head, body, pubic) | June 2022, June 2023, December 2023, June 2024, December 2024, June 2025, December 2025 | 7 | Q6 (full 10 marks) |
| Types of metamorphosis, hemimetabolous vs holometabolous | June 2022, June 2023, December 2023, June 2024, December 2024, June 2025, December 2025 | 7 | Q2(b) |
| Sand flies, Leishmania and kala-azar | June 2022, December 2022, June 2023, December 2023, June 2024, June 2025, December 2025 | 7 | Not asked in June 2026 |
| Integrated Vector Management (IVM) | June 2022, December 2022, June 2023, December 2024, June 2025, December 2025 | 6 | Q4 and Q7(d) |
| Housefly life cycle, transmission and control | June 2022, December 2022, June 2023, December 2023, June 2024, December 2024 | 6 | Q5 (solved on this page) |
| Vector, carrier and modes of transmission | June 2022, December 2022, June 2023, December 2024, June 2025, December 2025 | 6 | Q2(c) |
| Wings, halteres and elytra | June 2022, December 2022, June 2023, June 2024, June 2025, December 2025 | 6 | Q1(a)(iv), Q1(b)(i), Q2(d) |
| Compound eye, ommatidia and rhabdome | June 2022, December 2023, June 2024, December 2024, June 2025, December 2025 | 6 | Q7(a) |
| Haemolymph and hemocytes | June 2022, December 2022, December 2023, June 2024, December 2024, December 2025 | 6 | Q1(a)(ii) |
| Aedes mosquito and dengue | June 2022, December 2022, June 2023, June 2025, December 2025 | 5 | Q3 (solved on this page) |
| Chagas disease and reduviid bugs | June 2023, June 2024, December 2024, June 2025 | 4 | Q7(b) |
| Mosquito nets: ITNs, modified nets and LLINs | December 2023, June 2024 | 2 | Q2(a) |
| Vectorial capacity | June 2023, June 2025 | 2 | Q7(c) |
Counts come from the eight papers published on webservices.ignou.ac.in and ignou.ac.in: June 2022, December 2022, June 2023, December 2023, June 2024, December 2024, June 2025 and December 2025. A topic is counted once per paper, whether it came as a one-mark item or a full question.
Sand flies and kala-azar are the clear gap: seen in 7 of 8 papers but skipped in June 2026. For a ranked list built on the same method, see our IGNOU Solved Guess Paper page before the December 2026 exam.
Hit rate: 12 of the 13 tracked topics came back in June 2026 = 92%. Only 4 of those 12 returned as a full 10-mark question (lice, IVM, houseflies and Aedes); the other 8 came as 5-mark notes, 2.5-mark differences or one-mark items.
Two topics have not missed a paper since June 2023: human lice and metamorphosis, now 7 papers in a row counting June 2026. Houseflies ran for six straight papers from June 2022 to December 2024, skipped June and December 2025, and came back in June 2026.
Units and blocks June 2026 used and skipped
June 2026 drew its full questions from Blocks 2, 3 and 4 but left two named units with nothing: Unit 11 on Culex and Unit 13 on sand flies.
Block 4 was the densest: Q4 (IVM) and Q5 (houseflies) as full questions, plus ATSBs and Wolbachia in Q1 and genetic control as an optional note. Block 3 gave one full question, Q3 on Aedes. Block 2 gave Q6 on lice and the Chagas note, while rat fleas, plague and bed bugs were not touched. Block 1 fed most of Q1 and two of the four Q2 differences.
Unit 10 was used only by half. Genetic control of Anopheles came as one optional 5-mark note, but the malaria parasite's cycle and the Anopheles life cycle were not asked at all. That unexamined half is a strong candidate for December.
The dead Unit 13 lines up exactly with the biggest skipped topic in the repeat table, sand flies and kala-azar. Two independent signals pointing at the same unit is the strongest evidence on this page.
Q1: 8 of its 10 one-mark items (chloride cells, hemocytes, air sacs, halteres, tegmina, raptorial leg, glial cells, tymbal organ) come from Block 1 insect basics, and only ATSBs and Wolbachia come from the control units. Since Q1 is compulsory, Block 1 cannot be skipped.
Volume 2 (Blocks 3 and 4) alone gives three complete optional answers, Q3, Q4 and Q5, and a fourth only if both vectorial capacity and genetic control of Anopheles sit in Volume 2. Volume 1 alone gives Q6 and Q7 (compound eye + Chagas) in full and Q2 at 7.5 of 10, since the ITN vs LLIN difference belongs to the control units. That is three optional questions, one short of the four you must write. Neither volume clears the paper alone, and Volume 2 is the stronger half.
June and December papers compared
The eight earlier papers split evenly, four June and four December, so a session comparison is fair, and only one topic leans fully to one side.
| Topic | June papers (of 4) | December papers (of 4) |
|---|---|---|
| Human lice | 4 | 3 |
| Types of metamorphosis | 4 | 3 |
| Sand flies and kala-azar | 4 | 3 |
| Integrated Vector Management | 3 | 3 |
| Housefly | 3 | 3 |
| Vector, carrier and transmission | 3 | 3 |
| Wings, halteres and elytra | 4 | 2 |
| Compound eye | 3 | 3 |
| Haemolymph and hemocytes | 2 | 4 |
| Aedes and dengue | 3 | 2 |
| Chagas disease | 3 | 1 |
| Mosquito nets | 1 | 1 |
| Vectorial capacity | 2 | 0 |
Vectorial capacity is the only topic that scores zero on one side: June 2023, June 2025 and now June 2026, never in December. With only three appearances it is a thin pattern, but it does mean the topic is a lower priority for a December attempt. Every other topic has appeared in both sessions, so the session does not change the shortlist much.
The two samples on this page, Aedes and houseflies, both appear in June and December papers, so the page serves either attempt equally.
Topics to revise first for December 2026
The skipped topics with the longest exam history and the emptiest units in June 2026 come first.
- Sand flies, Leishmania and kala-azar: in 7 of 8 earlier papers, including 3 of 4 December papers, skipped in June 2026, and its unit (Unit 13) fed nothing. Two signals agree, so this is the top pick.
- Anopheles life cycle and malaria: Unit 10 was only half used in June 2026, through one optional note on genetic control. The malaria cycle and the mosquito's life cycle were not asked. This topic is not tracked in the repeat table above, so its earlier count still needs checking.
- Culex, filariasis and Japanese Encephalitis: Unit 11 gave nothing in June 2026. Also not tracked in the repeat table above.
- Rat flea and plague, and bed bugs: the rest of Block 2 after lice and Chagas was untouched in June 2026. Also not tracked in the repeat table above.
- Human lice and metamorphosis: not skipped, but neither has missed a paper since June 2023. Keep both ready even though June 2026 asked them.
How our BZYET-143 answers are written and checked
Every BZYET-143 answer is written from the official June 2026 paper, matched to the course blocks, and sized to the marks printed beside the question.
We started with the June 2026 BZYET-143 paper as IGNOU published it, then studied the earlier papers from June 2022 onwards to see how examiners phrase lice, IVM and mosquito questions. You can compare those sessions yourself in our IGNOU Previous Year Question Paper collection.
Scientific names are written in italics, disease agents are named in full, and control methods follow the order used in Block 4: environmental, mechanical, chemical, biological and genetic. A one-mark function stays to one line, while a 10-mark answer gets an introduction, headed points and a short conclusion.
Prateek Talwar drafted the answers and Sheetal Kirola reviewed them for accuracy and exam fit. Where a question asks for only part of a topic, as Q4 does with mechanical and biological IVM measures, the answer stays inside that limit instead of padding with chemical control.
BZYET-143 solved file index: all 7 questions mapped to blocks
The full file answers all 7 questions of the June 2026 paper; 2 are on this page and 5 are in the full file only.
| Question | Topic asked | Course block | Where to read it |
|---|---|---|---|
| Q1 | Functions of five structures and five match pairs | Blocks 1, 2 and 4 | Full file only |
| Q2 | Four differences: nets, development, vector and carrier, forewings | Blocks 1, 2 and 4 | Full file only |
| Q3 | Aedes life cycle, dengue transmission, Aedes control | Block 3 | On this page |
| Q4 | Mechanical and biological measures in IVM | Block 4, Unit 15 | Full file only |
| Q5 | Housefly-borne diseases, transmission and control | Block 4 | On this page |
| Q6 | Medical importance of three human lice | Block 2 | Full file only |
| Q7 | Two short notes from four options | Blocks 1 to 4 | Full file only |
Q7 is solved for all four options, not just two, so you can choose the pair you are most confident with. Block mapping follows the eGyanKosh block titles; unit numbers other than 10, 11, 13 and 15 are still being checked.
Programmes that include BZYET-143 Insect Vectors
BZYET-143 is part of the IGNOU B.Sc. (General) programme, BSCG, and is taken by learners who choose Zoology as one of their disciplines.
In IGNOU course codes, the B marks a bachelor course, ZY marks Zoology, and the E and T mark an elective theory paper. The June 2026 paper prints the programme as B.Sc. (General) (with Zoology), so this solved file is written for IGNOU Bachelor of Science (General) learners in the Zoology stream.
BZYET-143 carries 4 credits as a theory course, and its practical side sits in a separate 2-credit lab course, BZYEL-144 Insect Vectors and Vector Borne Diseases: Laboratory. This solved paper covers the theory term-end exam only; lab work is assessed under BZYEL-144.
Learners who studied the life sciences in Class 12 usually find the vector and disease units familiar, while the anatomy of insects in Block 1 needs more diagram practice. The course also suits students heading for public health, entomology or laboratory roles.
Get the full BZYET-143 Solved Question Paper on WhatsApp
Message WhatsApp 9899436384 with the code BZYET 143 to get the complete solved file with answers to all 7 June 2026 questions.
The IGNOU BZYET-143 Solved Question Paper file covers the 2 answers shown above plus the 5 that are not on this page: Q1, Q2, Q4, Q6 and Q7, with all four Q7 options solved. Our team confirms the price and shares the PDF on the same chat.
Tip: mention June 2026 in your message. If you also need answers for an earlier session of this course, ask in the same chat and we will tell you what is ready.
BZYET-143 Insect Vectors and Vector Borne Diseases FAQs
What does the BZYET-143 Solved Question Paper June 2026 include?
It includes complete answers to all 7 questions of the IGNOU June 2026 BZYET-143 Insect Vectors and Vector Borne Diseases paper. Q1 covers the ten one-mark parts, Q2 the four differences, and Q3 to Q7 the 10-mark long answers and short notes. Two answers, Q3 on Aedes and Q5 on houseflies, are shown in full on this page so you can judge the quality first.
How do I get the full BZYET-143 solved file on WhatsApp?
Send a message to WhatsApp 9899436384 with the code BZYET 143 and the session June 2026. Our team replies with the price and payment details, and the complete PDF is shared on the same chat. The file carries answers to all 7 questions in the paper: the 2 you can read on this page and the 5 that are listed here only as question text.
How many questions do I have to attempt in the BZYET-143 exam?
You attempt five questions in the BZYET-143 term-end exam. Question 1 is compulsory and carries 10 marks split into ten one-mark parts. You then choose any four of Questions 2 to 7, each worth 10 marks, to reach the maximum of 50. The paper runs for 2 hours, so plan roughly 20 minutes per long answer and keep time for diagrams.
Which BZYET-143 topics repeat most often in IGNOU papers?
Across the eight official BZYET-143 papers from June 2022 to December 2025, three topics appeared in seven papers each: human lice, types of metamorphosis, and sand flies with kala-azar. Integrated Vector Management, houseflies, vector and carrier concepts, wings, halteres and elytra, compound eye and haemolymph each appeared in six. June 2026 asked about most of these but left out sand flies, which makes them worth revising.
Who wrote and checked the BZYET-143 answers?
The answers were drafted by Prateek Talwar for Unnati Educations and reviewed by Sheetal Kirola before release. Each answer was matched against the BZYET-143 course blocks on eGyanKosh, checked for scientific names, disease agents and control methods, and sized to the marks printed in the paper, so a 10-mark answer reads like a 10-mark answer and a one-mark part stays to one line.
Which programme includes BZYET-143 Insect Vectors and Vector Borne Diseases?
BZYET-143 is offered in the IGNOU Bachelor of Science (General), programme code BSCG, for learners who take Zoology as a discipline. The code itself tells you its place: the E and T mark it as an elective theory course in Zoology. The June 2026 question paper prints the programme as B.Sc. (General) (with Zoology), so this solved paper is aimed at BSCG Zoology learners.
Can the BZYET-143 June 2026 solved paper help with the December 2026 exam?
Yes, it is a strong revision base. Several June 2026 questions, such as houseflies, Integrated Vector Management, lice and the ITN versus LLIN difference, have appeared in earlier BZYET-143 papers, so their answers are reusable. IGNOU does not repeat a paper word for word, though, so pair this file with your study material and give extra time to sand flies, malaria and plague.
How is BZYET-143 assessed apart from the term-end exam?
BZYET-143 has one tutor-marked assignment each year, and IGNOU gives it a 30 per cent weightage in your final result, with the term-end exam carrying the rest. The assignment is marked out of 100 and you need 35 per cent to pass it. Assignment questions often overlap with exam themes such as IVM, lice and Aedes, so revising one helps the other.
Who wrote and reviewed this page
This page was prepared by the Unnati Educations academic team, which writes solved papers, guess papers and study notes for IGNOU learners across the B.Sc. (General) Zoology electives.
Prateek Talwar, Academic Head, drafted the Q3 and Q5 answers and led the paper analysis on this page: the June-versus-December split of the 13 repeat topics, the block arithmetic showing that Q1 makes Block 1 unavoidable and that neither volume clears the paper alone, the finding that the dead Unit 13 matches the skipped sand-fly topic, and the December 2026 shortlist.
Sheetal Kirola reviewed the page. She checked that every question's parts add up to its marks (Q1 5×1 + 5×1, Q2 4×2.5, Q7 2×5), that the session count in each of the 13 repeat-table rows matches the sessions listed, the scientific names in both answers (Aedes aegypti, Aedes albopictus, Musca domestica, Spalangia, Muscidifurax, Beauveria bassiana), the dengue incubation periods (8 to 12 days in the mosquito, 4 to 7 days in humans) and the temephos dose of 1 ppm.