ICSE Class 10 Biology Sample Paper 2026 with Solutions

SECTION A (40 Marks)

(Attempt all questions from this Section.)

Question 1

Choose the correct answers to the questions from the given options. [15]
(Do not copy the question, write the correct answers only.)

(i) Allen’s blood report showed an abnormal decrease in the number of R.B.C. He is suffering from: [1 Mark]
(a) Polycythemia
(b) Erythropenia
(c) Glycosuria
(d) Haemophilia

Answer: (b) Erythropenia

Teacher's Note:
a) Erythropenia refers to a deficiency in the number of red blood cells.
b) Polycythemia refers to an abnormal increase in red blood cells.

(ii) A farmer notices that storing ripe mangoes with unripe ones speeds up the ripening process. The phytohormone primarily responsible for this phenomenon is: [1 Mark]
(a) Auxins
(b) Cytokinins
(c) Gibberellins
(d) Ethylene

Answer: (d) Ethylene

Teacher's Note:
a) Ethylene is a gaseous plant hormone that promotes fruit ripening.
b) Students must remember that ethylene is the only gaseous hormone known in plants.

(iii) Assertion (A) : Oxygen is produced during light dependent reactions of photosynthesis.
Reason (R) : Oxygen is released as a byproduct during photolysis. [1 Mark]
(a) (A) is true and (R) is false.
(b) (A) is false and (R) is true.
(c) Both (A) and (R) are true and (R) is the correct explanation of (A).
(d) Both (A) and (R) are true but (R) is not the correct explanation of (A).

Answer: (c) Both (A) and (R) are true and (R) is the correct explanation of (A).

Teacher's Note:
a) Photolysis of water occurs during the light-dependent phase, splitting water into hydrogen ions and oxygen.
b) Ensure that the reason correctly explains the mechanism behind oxygen evolution in photosynthesis.

(iv) Reena gets emotionally stressed when the school examinations are approaching. Which hormone is responsible for this condition? [1 Mark]
(a) Adrenaline
(b) Thyroxine
(c) Insulin
(d) Growth hormone

Answer: (a) Adrenaline

Teacher's Note:
a) Adrenaline prepares the body for emergency or stress situations (fight or flight response).
b) It is secreted by the adrenal medulla during stress.

(v) The diagram given below is that of a Neutrophil. The function is ___________: [1 Mark]
[Figure: Diagram of a neutrophil showing a multi-lobed nucleus and granular cytoplasm]
(a) secreting hormone
(b) transporting food
(c) phagocytosis
(d) producing antibodies

Answer: (c) phagocytosis

Teacher's Note:
a) Neutrophils are white blood cells that engulf foreign particles and bacteria by phagocytosis.
b) They form the body's first line of cellular defense against bacterial infection.

(vi) Assertion (A): Pituitary gland is known as the master gland.
Reason (R): It regulates the activities of other exocrine glands. [1 Mark]
(a) (A) is true and (R) is false.
(b) (A) is false and (R) is true.
(c) Both (A) and (R) are true and (R) is the correct explanation of (A).
(d) Both (A) and (R) are true but (R) is not the correct explanation of (A).

Answer: (a) (A) is true and (R) is false.

Teacher's Note:
a) The pituitary gland controls other endocrine glands, not exocrine glands.
b) Read the options carefully as terms like endocrine and exocrine are often confused by students.

(vii) Aruna went to a theatre to watch a movie on a bright sunny morning. As she came out of the theatre, she felt a dazzling effect and could not open her eyes. After a few minutes her vision became normal. This is due to: [1 Mark]
[Figure: A person shading their eyes with a hand against bright sunlight]
(a) Accommodation of eye
(b) Mutation
(c) Polarisation
(d) Adaptation of eyes

Answer: (d) Adaptation of eyes

Teacher's Note:
a) Dark adaptation to light adaptation involves the constriction of the pupil and bleaching of rhodopsin.
b) Do not confuse adaptation with accommodation, which is focusing on objects at different distances.

(viii) Reflex actions provide a survival advantage because they: [1 Mark]
(a) are controlled by the cerebrum.
(b) are controlled by the medulla oblongata.
(c) require no conscious thought, allowing rapid responses.
(d) always involve the spinal cord.

Answer: (c) require no conscious thought, allowing rapid responses.

Teacher's Note:
a) Reflex actions protect the body from sudden harm by bypassing conscious brain processing for speed.
b) Not all reflexes involve the spinal cord; some are cranial reflexes.

(ix) Industrial melanism is the phenomenon by which the peppered moth: [1 Mark]
(a) die due to industrial growth.
(b) in polluted areas, became darker in colour for better camouflage.
(c) became lighter in colour due to natural selection.
(d) became resistant to industrial pollution.

Answer: (b) in polluted areas, became darker in colour for better camouflage.

Teacher's Note:
a) Dark-colored moths survived better on soot-covered tree trunks due to natural selection.
b) This serves as a classic textbook example of natural selection driven by environmental changes.

(x) The hormone that maintains the thickening of the endometrium during pregnancy is: [1 Mark]
(a) Oestrogen
(b) ACTH
(c) Progesterone
(d) Oxytocin

Answer: (c) Progesterone

Teacher's Note:
a) Progesterone is secreted by the corpus luteum and placenta to maintain the uterine lining during pregnancy.
b) A drop in progesterone levels leads to menstruation or miscarriage.

(xi) The onset of menstruation in a human female is called: [1 Mark]
(a) Menopause
(b) Menarche
(c) Ovulation
(d) Oogenesis

Answer: (b) Menarche

Teacher's Note:
a) Menarche marks the beginning of the reproductive phase in human females.
b) Menopause is the permanent cessation of menstruation.

(xii) The number of autosomes and allosomes present in a human cell: [1 Mark]
(a) 22 allosomes, 1 autosome
(b) 22 pairs of autosomes, 1 pair of allosome
(c) 22 autosomes, 1 allosome
(d) 22 pairs of allosomes, 1 pair of autosome

Answer: (b) 22 pairs of autosomes, 1 pair of allosome

Teacher's Note:
a) Human somatic cells contain 46 chromosomes, arranged as 22 pairs of autosomes and 1 pair of sex chromosomes (allosomes).
b) Pay close attention to whether the question asks for individual chromosomes or pairs.

(xiii) Cultural revolution favours a steep rise in human population. Identify the correct sequence of revolution: [1 Mark]
(a) Tool making, Scientific and Industrial, Agricultural
(b) Agricultural, Tool making, Scientific and Industrial
(c) Scientific and Industrial, Agricultural, Tool making
(d) Tool making, Agricultural, Scientific and Industrial

Answer: (d) Tool making, Agricultural, Scientific and Industrial

Teacher's Note:
a) Human cultural evolution progressed from early tool making to agriculture, followed by the scientific and industrial revolutions.
b) Each stage significantly improved survival rates and food supply, driving population growth.

(xiv) Tanvi tried to match the phases of menstrual cycle with the number of days as given in the table below:
PHASE | DAYS
P - Follicular Phase | Day 5 - 12
Q - Luteal Phase | Day 15 - 28
R - Menstrual Phase | Day 3 - 5
S - Ovulatory Phase | Day 13 or 14
Identify the correct sequence: [1 Mark]
(a) P, Q, R, S
(b) Q, S, R, P
(c) R, P, S, Q
(d) S, R, P, Q

Answer: (c) R, P, S, Q

Teacher's Note:
a) The menstrual cycle begins with the Menstrual phase (R), followed by the Follicular phase (P), Ovulatory phase (S), and Luteal phase (Q).
b) Chronological ordering of biological cycles is a frequently tested concept.

(xv) Aditya who is fond of roller skating. Identify the correct terms which help him to maintain his body balance: [1 Mark]
[Figure: A boy balancing while roller skating]
(a) Cerebellum, Semicircular canals, Vestibule
(b) Vestibule, Sclera, Cerebrum
(c) Malleus, Semicircular canals, Utriculus
(d) Sacculus, Stapes, Cochlea

Answer: (a) Cerebellum, Semicircular canals, Vestibule

Teacher's Note:
a) The cerebellum coordinates muscular activity, while the semicircular canals and vestibule in the inner ear maintain dynamic and static balance.
b) Memorize the specific functions of the parts of the inner ear and hindbrain.

Question 2

(i) Give the biological/technical terms for the following: [5 Marks]
(a) A mixture of smoke and fog.
(b) The inner lining of uterus.
(c) The pressure that is responsible for the movement of water molecules across the cortical cells of the root.
(d) The ground substance present in a chloroplast.
(e) The fluid present between the layers of meninges.

Answer:
(a) Smog
(b) Endometrium
(c) Root pressure
(d) Stroma
(e) Cerebrospinal fluid

Teacher's Note:
a) Technical terms must be spelt correctly to secure full marks.
b) Root pressure and stroma are core physiological and structural terms.

(ii) Given below is the diagram of a human heart. Read the information below the diagram and fill in the blanks:
The human heart pumps blood throughout the body. It is the size of a large fist. The heart is located between the lungs in the thoracic cavity. It has four chambers. The heart functions all through the lifespan of a person and is responsible for the survival of the person.
The heart is enclosed by a membrane called (a) ____________ (Pericardium / Pleura). The ventricles give rise to two large blood vessels called (b) ____________ (Pulmonary vein / Pulmonary artery) and (c) ____________ (Aorta / Venacava). The flaps of the cuspid valves are kept in position by (d) ____________ (Chordae tendinae / Endometrium). (e) ____________ (Hepatic / Coronary) arteries supply oxygenated blood to the walls of the heart. [5 Marks]
[Figure: External ventral view of a human heart showing blood vessels, ventricles, and atria]

Answer:
(a) Pericardium
(b) Pulmonary artery
(c) Aorta
(d) Chordae tendinae
(e) Coronary

Teacher's Note:
a) Students should practice heart anatomy thoroughly as diagram-based fill-ups are common.
b) Note that chordae tendinae anchor the cuspid valves to prevent them from inverting into the atria.

(iii) Choose the odd term out from each of the following set of terms. Mention the category to which the remaining three belong: [5 Marks]
(a) Sulphur dioxide, Oxygen, Carbon monoxide, Nitrogen dioxide.
(b) Pons, Epidermis, Xylem, Phloem.
(c) Tympanum, Pinna, Auditory canal, Malleus.
(d) Ureter, Urethra, Uterus, Renal Pelvis.
(e) Stomata, Lenticles, Cuticle, Root hair.

Teacher's Note:
a) Identifying the odd term requires recognizing the common functional or structural grouping of the other three.
b) Root hair absorbs water, whereas stomata, lenticels, and cuticle are sites of transpiration.

(iv) Rajeev, a 10 year old boy, went to an Ophthalmologist to get his eyes tested. He noticed a poster in the clinic with questions related to the parts of human eye. Help Rajeev answer the questions: [5 Marks]
(a) Which is the fluid that lubricates the eye?
(b) Which cells help in colour vision?
(c) Which nerve sends impulses from the eyeball to the brain?
(d) Name the structure that gives colour to the eyes.
(e) Name the part that allows entry of light rays into the eye.

Answer:
(a) Tears (or Aqueous humor / Tear fluid)
(b) Cones
(c) Optic nerve
(d) Iris
(e) Pupil

Teacher's Note:
a) Cones are sensitive to bright light and color, while rods are sensitive to dim light.
b) The pupil regulates the amount of light entering the eye, controlled by the iris.

(v) Study the diagram given below and match the structure with its function:
Example: Scrotum - (f) [5 Marks]
[Figure: Diagram of human testis and associated ducts showing seminiferous tubules, efferent ducts, epididymis, vas deferens, interstitial cells, and scrotum]

Teacher's Note:
a) Matching questions test both anatomical identification and functional association.
b) Interstitial cells (cells of Leydig) are responsible for producing the male hormone testosterone.

SECTION B (40 Marks)

(Attempt any four questions from this Section.)

Question 3

(i) Explain the term Menarche. [1 Mark]

Answer:
It is the onset of menstruation in a young female around the age of 13 years.

Teacher's Note:
a) Menarche signifies the attainment of puberty in human females.
b) Keep definitions concise and accurate to secure full marks.

(ii) In what form is water lost during transpiration and guttation from plants? [2 Marks]

Answer:
1. Transpiration: Water is lost in the form of water vapour.
2. Guttation: Water is lost in the form of water droplets.

Teacher's Note:
a) Transpiration occurs mainly through stomata as a gas, driven by evaporation.
b) Guttation occurs through hydathodes at the leaf margins under high root pressure.

(iii) Ayush was in the final round of a carrom match. He was focussing intently on the strokes of the opponent player.
(a) Which part of the brain helps Ayush to focus on the game?
(b) Name the part of the brain that co-ordinates his muscles while using the striker. [2 Marks]
[Figure: Two boys playing carrom board, one aiming with a striker]

Answer:
(a) Cerebrum
(b) Cerebellum

Teacher's Note:
a) The cerebrum is the seat of intelligence, memory, and concentration.
b) The cerebellum is responsible for precise muscular coordination and balance.

(iv) State the permeability of cell membrane and cell wall. [2 Marks]

Answer:
1. Cell membrane: Semipermeable (or selectively permeable).
2. Cell wall: Freely permeable.

Teacher's Note:
a) The cell membrane allows only certain molecules to pass through based on size and solubility.
b) The plant cell wall, made of cellulose, allows free passage of water and dissolved substances.

(v) Draw a neat, labelled diagram of a cross section of an Artery and a Vein. [3 Marks]

Answer:
[Figure: Diagram of T.S. of an Artery and a Vein showing outer connective tissue, middle coat of muscle and elastic fibres, inner lining of endothelium, and lumen. The artery has a thick muscular wall and narrow lumen; the vein has a thin wall and wide lumen.]

Teacher's Note:
a) Arteries possess thick, muscular walls to withstand high blood pressure, whereas veins have thinner walls with valves.
b) Correct labeling of the lumen, muscular coat, and endothelium is essential for scoring full marks.

Question 4

(i) What is Excretion? [1 Mark]

Answer:
It is the removal of harmful nitrogenous waste products from the body.

Teacher's Note:
a) Excretion specifically refers to metabolic wastes like urea, uric acid, and creatinine.
b) Do not confuse excretion with egestion, which is the removal of undigested food.

(ii) Differentiate between Diabetes mellitus and Diabetes insipidus with reference to the hormone involved. [2 Marks]

Teacher's Note:
a) Diabetes mellitus is characterized by high blood glucose levels and sugar in the urine.
b) Diabetes insipidus results in excessive production of dilute urine due to a lack of ADH.

(iii) Give the common name and the scientific name of the plant on which Gregor Mendel conducted his breeding experiments. [2 Marks]

Answer:
1. Common name: Garden pea
2. Scientific name: Pisum sativum

Teacher's Note:
a) Scientific names must be correctly formatted: the genus name begins with a capital letter and the species name with a small letter.
b) Underlining binomial nomenclature separately when handwritten is standard practice.

(iv) Name the tonicity of the solutions for a living cell to show Endosmosis and Exosmosis. [2 Marks]

Answer:
1. Endosmosis: Hypotonic solution
2. Exosmosis: Hypertonic solution

Teacher's Note:
a) In a hypotonic solution, water enters the cell because the solute concentration outside is lower.
b) In a hypertonic solution, water leaves the cell due to a higher solute concentration outside.

(v) Plant hormones are produced in extremely low concentrations in plants to regulate the physiological processes and tropic movements -
(a) Name one plant hormone responsible for the changes shown in the above picture.
(b) Identify a hormone that has an opposite effect to the one depicted in the picture.
(c) Give an example of a plant that shows Thigmotropism. [3 Marks]
[Figure: Sequential diagram of leaves turning yellow, undergoing senescence, and leaf fall starting from a healthy green plant]

Answer:
(a) Abscisic acid (or Ethylene)
(b) Auxin (or Cytokinin)
(c) Pea plant (or Grapevine / Passion flower / Ivy)

Teacher's Note:
a) Abscisic acid and ethylene promote senescence, aging, and leaf fall in plants.
b) Auxins and cytokinins promote growth and delay leaf aging.

Question 5

(i) What are non-biodegradable wastes? [1 Mark]

Answer:
Materials that cannot be broken down by microorganisms and persist in the environment causing pollution.

Teacher's Note:
a) Plastics and synthetic polymers are common examples of non-biodegradable wastes.
b) Mentioning their persistence in the environment is crucial for full credit.

(ii) Mention any two objectives of the Swachh Bharat Abhiyan. [2 Marks]

Answer:
1. To eliminate open defecation.
2. To clean streets, roads, and infrastructure of cities and towns.

Teacher's Note:
a) The nationwide campaign aims to improve sanitation and waste management.
b) Students can also mention promoting public awareness regarding cleanliness.

(iii) Arrange the following food chain in a proper sequence:
(a) Small fish, Penguin, Algae, Seal, Mosquito larvae
(b) Woodpecker, Caterpillar, Mountain lion, Fox, Cabbage [2 Marks]

Answer:
(a) Algae → Mosquito larvae → Small fish → Seal → Penguin
(b) Cabbage → Caterpillar → Woodpecker → Fox → Mountain lion

Teacher's Note:
a) Food chains always begin with a producer and end with top carnivores.
b) Ensure arrows point in the direction of energy flow (from prey to predator).

(iv) Mention the number of cranial nerves and spinal nerves in a human being. [2 Marks]

Answer:
1. Cranial nerves: 12 pairs
2. Spinal nerves: 31 pairs

Teacher's Note:
a) Cranial nerves emerge directly from the brain, while spinal nerves arise from the spinal cord.
b) Always specify "pairs" when stating the number of peripheral nerves.

(v) Surya used a plant with variegated leaves for an experiment on photosynthesis. He tested a leaf with iodine after keeping the plant in sunlight for a few hours.
(a) Which parts of the leaf will turn blue black after the iodine test?
(b) What does this tell us about the role of chlorophyll in photosynthesis?
(c) Write the overall chemical equation for photosynthesis. [3 Marks]
[Figure: Potted plant with variegated leaves showing green and white patches]

Answer:
(a) Green parts of the leaf.
(b) Chlorophyll is essential for photosynthesis as starch is formed only in chlorophyll-containing regions.
(c) 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂ + 6H₂O
(Carbon dioxide) (Water) (Glucose) (Oxygen) (Water)

Teacher's Note:
a) Variegated leaves have green areas with chlorophyll and white/yellow areas without chlorophyll.
b) The chemical equation must include sunlight and chlorophyll above and below the arrow, and water on both sides for complete accuracy.

Question 6

(i) State Mendel’s Law of Dominance. [1 Mark]

Answer:
Out of a pair of contrasting characters present together, only one is able to express itself while the other remains suppressed.

Teacher's Note:
a) The allele that expresses itself is termed dominant, and the suppressed one is recessive.
b) This law explains the monohybrid cross phenotypic ratio of 3:1 in the F2 generation.

(ii) State the rate of transpiration when the air surrounding a plant has:
(a) more atmospheric humidity.
(b) hot and dry air. [2 Marks]

Answer:
(a) Less transpiration
(b) More transpiration

Teacher's Note:
a) High humidity decreases the diffusion gradient between the leaf interior and surrounding air, reducing transpiration.
b) Hot and dry air increases the evaporation rate, accelerating transpiration.

(iii) Expand the following abbreviations:
(a) ACTH
(b) ADH [2 Marks]

Answer:
(a) Adrenocorticotropic Hormone
(b) Antidiuretic Hormone

Teacher's Note:
a) Spelling of hormonal expansions must be exact to prevent loss of marks.
b) ADH is also known as vasopressin and regulates water reabsorption in the kidneys.

(iv) Which part of the ear equalizes air pressure on either side of the ear drum? Where is this structure located? [2 Marks]

Answer:
1. Eustachian tube.
2. It connects the middle ear to the pharynx (throat).

Teacher's Note:
a) Equalizing pressure prevents damage to the tympanic membrane during altitude changes.
b) Memorize both the name of the structure and its precise anatomical location.

(v) Santosh loved his garden, especially his pea plants. One year, he noticed that all the pea plants he grew from one batch of seeds had round seeds. Curious, he took the seeds from one of those plants and grew a new generation. To his surprise, 75% of the new plants had round seeds, but 25% had wrinkled seeds.
(a) What were the genotypes of the parent plants that Santosh originally planted?
(b) Which trait is dominant - round or wrinkled seeds?
(c) What is the genotypic ratio of the second generation (F2) plants? [3 Marks]
[Figure: Two round seeds and wrinkled seeds representation labelled (1) Seed Shape]

Answer:
(a) Heterozygous dominant - Rr
(b) Round
(c) 1:2:1 (RR : Rr : rr)

Teacher's Note:
a) The 3:1 phenotypic ratio in the F2 generation confirms that the parents were heterozygous.
b) Distinguish clearly between phenotypic ratio (3:1) and genotypic ratio (1:2:1).

Question 7

(i) Explain the term Natality. [1 Mark]

Answer:
It is the number of live births per 1000 people of population per year.

Teacher's Note:
a) Natality is a key demographic factor contributing to population increase.
b) Contrast this with mortality, which is the death rate per 1000 individuals per year.

(ii) Distinguish between Sympathetic system and Parasympathetic system on the basis of heartbeat. [2 Marks]

Teacher's Note:
a) The sympathetic nervous system prepares the body for action (fight or flight).
b) The parasympathetic nervous system conserves energy and calms the body down (rest and digest).

(iii) Meena covered a potted plant as shown below with a transparent plastic bag. She observed water droplets inside the bag after a few hours when kept in sunlight.
(a) Name the process that resulted in the formation of water droplets inside the bag.
(b) Define the process mentioned above. [2 Marks]
[Figure: Potted plant enclosed in a transparent polythene bag tied at the base, showing water droplets condensed on the inside surface]

Answer:
(a) Transpiration
(b) It is the loss of water as water vapour from the aerial parts of a plant.

Teacher's Note:
a) Transpiration creates a suction pull that helps in the ascent of sap.
b) Control setups without plants are often used in laboratories to rule out condensation from the soil.

(iv) Mention the regions of the kidney where we can find glomerulus and Henle’s loop. [2 Marks]

Answer:
1. Glomerulus: Renal cortex
2. Henle's loop: Renal medulla

Teacher's Note:
a) The renal cortex contains the Malpighian corpuscles (Bowman's capsule and glomerulus).
b) The renal medulla contains the loops of Henle and collecting ducts.

(v) Draw a neat, labelled diagram to show the internal structure of a root hair. [3 Marks]

Answer:
[Figure: Diagram of a root hair cell showing epidermal cell, cell wall, cytoplasm, vacuole, cell membrane, nucleus, fully grown root hair, and newly growing root hairs attached to a root section]

Teacher's Note:
a) Root hairs are single-celled extensions of epidermal cells that increase the surface area for water absorption.
b) Ensure proper labeling of the large vacuole, cell wall, cell membrane, and nucleus.

Question 8

(i) How does the ozone layer depletion affect life on earth? [1 Mark]

Answer:
Causes skin cancer, cataracts, reduced crop yields, and harms marine life.

Teacher's Note:
a) Depletion of the ozone layer allows harmful ultraviolet (UV) radiation from the sun to reach the Earth's surface.
b) Chlorofluorocarbons (CFCs) are the primary pollutants responsible for ozone depletion.

(ii) Mention two body features of Australopithecus. [2 Marks]

Answer:
1. Chin absent
2. Prognathus face (or Projecting eyebrow ridges)

Teacher's Note:
a) Australopithecus represents an early hominid ancestor showing ape-like and human-like characters.
b) Mentioning any two distinct skeletal features from the syllabus is sufficient.

(iii) Identical twins are always of the same gender. Explain why. [2 Marks]

Answer:
Because they develop from a single fertilised egg (zygote) that splits into two embryos.

Teacher's Note:
a) Since they originate from the same zygote, they share identical genetic makeup including the same sex chromosomes.
b) Contrast this with fraternal twins, which develop from two separate eggs and can be of different genders.

(iv) We should not insert sharp objects into the ear to remove ear wax. Give a suitable reason. [2 Marks]

Answer:
It may rupture the ear drum (tympanic membrane) leading to deafness.

Teacher's Note:
a) The eardrum is a delicate membrane that vibrates in response to sound waves.
b) Inserting sharp objects can also push ear wax deeper or damage the delicate bones of the middle ear.

(v) In a school experiment, a few students grow plants in pots placed horizontally as shown below. After a few days, the students observed that the roots bent downward, and the shoots curved upward.
(a) Name the tropic movement seen in shoots.
(b) Why do roots always grow downwards?
(c) Which phytohormone regulates the above tropic movements? [3 Marks]
[Figure: Potted plant placed horizontally on its side showing roots bending downward and the shoot curving upward against gravity]

Answer:
(a) Phototropism
(b) Because the roots are positively geotropic and hydrotropic.
(c) Auxins

Teacher's Note:
a) Unequal distribution of auxins in response to gravity and light causes differential growth in roots and shoots.
b) Shoots are negatively geotropic and positively phototropic, whereas roots show the exact opposite behavior.