NEET WEEKLY TEST BIOLOGY (CHANMARI AND SDA) (19.09.2026)

2. Which of the following statements best explains why Whittaker’s five-kingdom classification was considered an improvement over earlier classification systems?

1. It classified organisms exclusively according to their evolutionary history and completely eliminated the importance of morphology.

2. It separated organisms into kingdoms solely according to whether they were useful or harmful to humans.

3. It considered fundamental differences in cellular organisation, body organisation, mode of nutrition, reproduction and evolutionary relationships, thereby separating major groups such as Monera and Fungi.

4. It divided all organisms into five kingdoms of equal size and equal evolutionary complexity.

3. During photophosphorylation, the proton gradient across the thylakoid membrane is mainly generated due to:

1. Splitting of water on the stromal side
2. Movement of protons into the stroma by ATP synthase
3. Proton accumulation in the thylakoid lumen
4. Reduction of NADP⁺ in the thylakoid lumen

4. Observe the following statements and select the statement that correctly describe first polar body

1. They are formed after first mitotic division
2. They contain half the number of chromosomes, ie 23
3. They have either one X or one Y chromosomes
4. They give rise to one ovum

5. Consider the following statements about the Calvin cycle:
A. CO₂ is fixed by RuBisCO.
B. The first stable product of the C3 cycle is a 3-carbon compound.
C. ATP and NADPH are consumed during the reduction phase.
D. RuBP is regenerated during the regeneration phase.
Which is correct?

1. A and B only
2. B, C and D only
3. A, C and D only
4. A, B, C and D

6. The following graph shows the levels of pituitary hormones during menstrual cycle. What do X and Y represent?


1. X – FSH, Y – LH
2. X – Estrogen, Y – Progesterone
3. X – Progesterone, Y – Estrogen
4. X – LH, Y – FSH

7. Engelmann’s experiment provided evidence that:

1. All wavelengths of visible light are equally effective in photosynthesis.
2. Chlorophyll absorbs only red light.
3. Photosynthetic activity is highest in blue and red regions of the spectrum.
4. Green light is the most effective for photosynthesis.

8. From the options given below, select the group of cells which are haploid

1. Spermatogonia, oogonia, ovum
2. Primary spermatocyte, secondary spermatocyte, spermatids
3. Primary oocyte, secondary oocyte, spermatozoa
4. Secondary spermatocyte, secondary oocyte, second polar body

9. Which observation in Engelmann’s experiment helped establish the relationship between wavelength of light and photosynthetic activity?

1. Algal cells became green under red light.
2. Aerobic bacteria accumulated in regions receiving blue and red light.
3. CO₂ concentration increased around the algal filament.
4. Glucose accumulated specifically in blue-light regions.

10. Which cells of blastocyst contain stem cells

1. Inner cell mass
2. Outer cell mass
3. Trophoblast
4. Both 2 and 3

11. ________ is secreted by secondary oocyte

1. Corona radiata
2. Corpus luteum
3. Zona pellucida
4. FSH

12. Which statement correctly distinguishes the observations of Priestley and Ingenhousz?

1. Priestley showed that plants release oxygen, while Ingenhousz showed that this occurs only in darkness.
2. Priestley showed that plants can restore air, while Ingenhousz demonstrated that this occurs only in the presence of sunlight and by green parts of plants.
3. Priestley demonstrated starch formation, while Ingenhousz demonstrated oxygen evolution.
4. Both demonstrated that only green parts of plants carry out photosynthesis.

13. The function of male accessory ducts and glands are maintained by

1. Hypothalamus
2. Anterior-pituitary gland
3. Androgens
4. LH and FSH

14. Which sequence correctly represents the major contribution of the early experiments?

1. Priestley → starch formation; Ingenhousz → CO₂ fixation; Sachs → oxygen evolution
2. Priestley → restoration of air; Ingenhousz → requirement of light and green parts; Sachs → starch formation
3. Priestley → action spectrum; Ingenhousz → starch formation; Sachs → restoration of air
4. Priestley → chlorophyll discovery; Ingenhousz → oxygen evolution; Sachs → action spectrum

15. A microorganism lacks a cell wall and can survive in places where many other bacteria cannot. It is considered one of the smallest living cellular organisms. Which organism best fits this description?

1. Nostoc
2. Mycoplasma
3. Methanobacterium
4. Saccharomyces

16. The functional unit of testis of male is

1. Sperms
2. Seminiferous tubule
3. Testicular lobule
4. Sertoli cells

17. Choose the incorrect statement from the following

1. Ovum and sperm had to be transported simultaneously to the ampulla for fertilization to occur.
2. Zona pellucida ensures the entry of only one sperm to fertilize the ovum.
3. The second meiotic division of oocyte is unequal and results in the formation of second polar body.
4. The meiotic division of zygotes starts as the zygote moves through the isthmus of the oviduct.

18. The electrons lost by the reaction centre of PSII are ultimately replaced by electrons obtained from:

1. NADPH
2. ATP
3. Photolysis of water
4. RuBP

19. Which of the following correctly distinguishes the absorption spectrum from the action spectrum of photosynthesis?

1. Absorption spectrum shows the rate of photosynthesis at different wavelengths, whereas action spectrum shows the amount of light absorbed by pigments.
2. Absorption spectrum shows the wavelengths of light absorbed by a photosynthetic pigment, whereas action spectrum shows the effectiveness of different wavelengths in carrying out photosynthesis.
3. Both absorption and action spectra show the amount of oxygen released at different wavelengths.
4. Absorption spectrum represents the effectiveness of different wavelengths in photosynthesis, whereas action spectrum represents light absorption by individual pigments.

20. In non-cyclic electron transport, the correct overall direction of electron flow is:

1. Water → PSII → PSI → NADP⁺
2. NADP⁺ → PSI → PSII → water
3. Water → PSI → PSII → NADP⁺
4. PSII → water → PSI → NADP⁺

21. A freshwater organism is observed to possess chloroplasts and a flexible body without a conventional cell wall. In bright light, it performs photosynthesis, whereas under conditions where photosynthesis is not possible, it can obtain nutrition heterotrophically. Based solely on these characteristics, a student concludes that the organism must belong to Plantae.
Which statement most effectively challenges the student’s conclusion?

1. Photosynthesis is restricted exclusively to cyanobacteria.
2. The presence of chloroplasts automatically places an organism in Fungi.
3. Euglenoids possess chloroplasts but are\ placed in Protista because of their eukaryotic organisation and distinctive\ pellicle.
4. All organisms showing heterotrophic nutrition necessarily belong to Monera.

22. During photophosphorylation, ATP synthesis occurs when:

1. Protons move from stroma into the thylakoid lumen through ATP synthase.
2. Protons move from the thylakoid lumen into the stroma through ATP synthase.
3. Electrons move directly through ATP synthase.
4. NADPH passes through ATP synthase.

23. According to the law of limiting factors, if several factors affect a process and one of them is present in an amount that limits the process, then:

1. Increasing all factors will always increase the rate.
2. Increasing the limiting factor will\ increase the rate until another factor becomes limiting.
3. The rate remains unchanged regardless of the limiting factor.
4. Only light can act as a limiting factor.

24. Consider the following statements:
A. PSII is associated with P680.
B. PSI is associated with P700.
C. Photolysis of water is associated with PSII.
D. PSI directly participates in the reduction of NADP⁺.
Which are correct?

1. A and B only
2. A, B and C only
3. B, C and D only
4. A, B, C and D

25. A plant requires additional ATP but does not require additional NADPH. Which process would be particularly useful?

1. Non-cyclic photophosphorylation
2. Cyclic photophosphorylation
3. Photolysis of water
4. Reduction of NADP⁺

26. Which of the following correctly explains why cyclic photophosphorylation does not produce NADPH?

1. PSI cannot absorb light.
2. Electrons return to the same photosystem instead of being transferred to NADP⁺.
3. PSII supplies electrons directly to NADP⁺.
4. Water is not available during cyclic photophosphorylation.

27. Read the following statements carefully:
Statement I: Archaebacteria are different from other bacteria in the composition of their cell wall and cell membrane.
Statement II: Methanogens are commonly found in the rumen of cattle, where they contribute to the production of methane.
Statement III: All archaebacteria obtain their energy by performing oxygenic photosynthesis similar to cyanobacteria.
Which of the following correctly describes these statements?

1. Statement I and II are correct, while Statement III is incorrect
2. Statement I is incorrect, while Statements II and III are correct
3. Statements I and III are correct, while Statement II is incorrect
4. All three statements are correct

28. If 3 molecules of CO₂ are fixed through the Calvin cycle, how many ATP and NADPH molecules are required?

1. 9 ATP + 6 NADPH
2. 6 ATP + 9 NADPH
3. 18 ATP + 12 NADPH
4. 9 ATP + 9 NADPH

29. Which sequence correctly represents increasing complexity of cellular organisation?

1. Virus → Bacterium → Amoeba → Fungus
2. Bacterium → Virus → Amoeba → Fungus
3. Virus → Amoeba → Bacterium → Fungus
4. Fungus → Amoeba → Bacterium → Virus

30. Assertion (A): Endometrium is necessary for implantation of blastocyst
      Reason (R): In the absence of fertilization, the corpus luteum degenerates that causes disintegration of endometrium
Considering the above statements, choose the correct answer from the options given below:

1. A is false but R is true
2. Both A and R are true and R is the correct explanation of A
3. Both A and R are true but R is not the correct explanation of A
4. A is true but R is false

31. Which of the following statements about cyanobacteria is NOT correct?

1. They are prokaryotic.
2. They may possess specialised cells called heterocysts.
3. Some can fix atmospheric nitrogen.
4. They possess membrane-bound chloroplasts containing chlorophyll-a.

32. Which of the following statements regarding morula in human is correct

1. It has far less cytoplasm as well as less DNA than an uncleaved zygote 
2. It has almost equal quantity of cytoplasm as an uncleaved zygote but much more DNA
3. It has more or less equal quantity of cytoplasm and DNA as in uncleaved zygote
4. It has more cytoplasm and DNA than an uncleaved zygote

33. During a phenomenon known as a “red tide,” large numbers of certain organisms multiply near the surface of seawater. Which organism is classically associated with this phenomenon?

1. Nostoc
2. Gonyaulax
3. Rhizopus
4. Methanobacterium

34. Assertion (A): The descent of testes occurs by the end of seventh of fetal development
      Reason (R): The cooler temperature outside the abdominal cavity is necessary for spermatogenesis

1. Both A and R are true and R is the correct explanation of A
2. Both A and R are true but R is not the correct explanation of A
3. A is true but R is false
4. A is false but R is true

35. Identify the figures A, B and C given below.


1. A–Euglena, B–Paramecium, C–Agaricus
2. A–Euglena, B–Planaria, C–Agaricus
3. A–Planaria, B–Paramecium, C–Agaricus
4. A–Euglena, B–Paramecium, C– Aspergillus

36. Consider the following statements about organisms included in Kingdom Fungi:
1. Their cell walls are generally made of chitin.
2. Their mode of nutrition is heterotrophic.
3. Their hyphae may be septate or aseptate depending upon the group.
4. All fungi reproduce exclusively by sexual reproduction.
5. Some fungi reproduce by spores.
Which of the following represents the correct combination?

1. 1, 2, 3 and 5 only
2. 1, 2 and 4 only
3. 2, 3 and 4 only
4. 1, 3, 4 and 5 only

37. Assertion (A): Euglenoids are placed under Protista rather than Plantae.
      Reason (R): Euglenoids lack a cell wall and possess a flexible protein-rich layer called a pellicle.

1. Both A and R are true, and R correctly explains A
2. Both A and R are true, but R does not correctly explain A
3. A is true, but R is false
4. A is false, but R is true

38. The following organisms are arranged into two groups by a student:
Group I: Rhizopus, Mucor, Albugo
Group II: Penicillium, Aspergillus, Neurospora
The student then concludes that all organisms in Group I possess aseptate mycelium and all organisms in Group II possess septate mycelium.
Which evaluation is most appropriate based on the classification?

1. Both groups consist entirely of organisms with aseptate mycelium
2. Group I phycomycetes, mainly while represents Group II represents ascomycetes
3. Group I represents ascomycetes, while Group II represents basidiomycetes
4. All organisms in both groups belong to Deuteromycete

39. A fungal organism has a multinucleate, aseptate, branched mycelium and reproduces asexually by sporangiospores.
Which group is it most likely associated with in the classification?

1. Deuteromycetes
2. Ascomycetes
3. Basidiomycetes
4. Phycomycetes

40. Which of the following pairs is incorrectly matched?

1. Rhizopus — Bread mould
2. Penicillium — Ascomycetes
3. Agaricus — Basidiomycetes
4. Puccinia — Deuteromycetes

41. Statement A: Soon after the placenta is delivered, the infant is also expelled out of the uterus
Statement B: Doctors inject oxytocin to induce delivery of baby when it is not secreted in adequate amount from maternal pituitary

1. Both statements A and B are correct
2. Both statements A and B are incorrect
3. Only statement A is correct
4. Only statement B is correct

42. Cleavage in mammals

1. Holoblastic equal
2. Holoblastic unequal
3. Superficial
4. Discoidal

43. A student studying five-kingdom classification makes the following observations about four organisms:
(a) Organism P is unicellular, eukaryotic and possesses a flexible pellicle.
(b) Organism Q is prokaryotic and can perform photosynthesis.
(c) Organism R is eukaryotic, filamentous and possesses a chitinous cell wall.
(d) Organism S is acellular and can multiply only inside a living host.
Which of the following combinations correctly identifies P, Q, R and S respectively?

1. Cyanobacterium, Euglena, fungus, virus
2. Euglena, cyanobacterium, fungus, virus
3. Euglena, fungus, cyanobacterium, virus
4. Virus, cyanobacterium, fungus, Euglena

44. Arrange the following parts in human mammary gland, transversing the route of milk ejection
A. Mammary duct
B. Lactiferous duct
C. Mammary alveolus
D. Ampulla
E. Mammary tubule
Choose the correct answer from the options given below

1. D – C – E – A – B
2. C – E – B – A – D
3. C – E – A – D – B
4. A – C – E – D – B

45. The two-kingdom classification proposed by Linnaeus divided all living organisms into Plantae and Animalia. However, several organisms could not be satisfactorily placed in either kingdom. Which combination of characteristics most directly explains the inadequacy of this system?

1. It failed to distinguish organisms based on habitat, geographical distribution and economic importance.
2. It did not adequately distinguish between prokaryotic and eukaryotic organisms, unicellular and multicellular forms, and autotrophic and heterotrophic modes of nutrition.
3. It classified all organisms according to their mode of reproduction but ignored It classified all organisms according to their mode of reproduction but ignored their evolutionary relationships.
4. It placed all organisms possessing chlorophyll under Animalia and all non chlorophyllous organisms under Plantae.