3. The figure below compares a part of our eye with a part of a photographic camera. (a) Name the corresponding parts of the eye and the camera shown here that are comparable in function. (b)...
E. STRUCTURED/APPLICATION/SKILL TYPE
read more
Class 10
E. STRUCTURED/APPLICATION/SKILL TYPE
2. With reference to the human ear, answer the questions that follow: a. Given the technical term for the structure found in the inner ear. b. Name the three small bones present in the...
E. STRUCTURED/APPLICATION/SKILL TYPE
1. With reference to the functioning of the eye, answer the questions that follow: a. What is meant by power of accommodation of the eye? b. What is the shape of the lens during (1) near...
D. LONG ANSWER TYPE
8. What is meant by power of accommodation of the eye? Name the muscles of the eye responsible for the same…………………. Solution:- The image of an object should be in sharp focus in each eye to view it...
D. LONG ANSWER TYPE
7. Name the three ear ossicles. How do they contribute to the mechanism of hearing? Solution:- Malleus (hammer), Incus (anvil), and Stapes (staples) are three Greek gods (stirrup). The ear ossicles...
D. LONG ANSWER TYPE
6. Enumerate the common defects of vision, their causes and the possible methods of correcting them. Solution:- Defect of visionCauseCorrective measure1. MyopiaThe eyeball is lengthened from front...
D. LONG ANSWER TYPE
5. You do not enjoy watching a movie from a very short distance from the screen in a cinema hall. Why? Solution:- A blurred image is generated when watching a movie from a very close distance....
D. LONG ANSWER TYPE
4. Explain the terms ‘adaptation’ and ‘accommodation’ with reference to the eye. Solution:- Adaptation: For a brief period of time, when you move from a highly lit area to a dark environment (such...
D. LONG ANSWER TYPE
3. By closing the eyes and gently pressing them by your palms, you may see some specks of brilliant light. How do you get this sensation while there is no light entering your eyes? Solution:- We can...
D. LONG ANSWER TYPE
2. Sometimes you remember a vivid picture of a dream you saw. What is the role of your eyes in this experience? Solution:- Through the eyes, the brain perceives a detailed picture of the dream. Our...
D. LONG ANSWER TYPE
1. Describe the mechanism of focusing the image of a distant object in your eye when you raise your head after reading a book. Solution:- The image of an object should be in sharp focus in each eye...
C. SHORT ANSWER TYPE
10. Complete the following table by filling in the blank spaces. Structure Function 1. Yellow spot (i) …………….. 2. ………………… (ii) Transfers impulse from inner ear to brain 3. ………………… (iii) Helps to...
C. SHORT ANSWER TYPE
9. Where are the following located? Briefly mention the function of each: (a) Oval window (b) Cochlea (c) Semicircular canals (d) Utriculus Solution:- (a) Oval window is a membrane-covered opening...
C. SHORT ANSWER TYPE
8. What is meant by optical illusion? Give one example. Pictures are shown on a screen at a rate of around 24 frames per second in a movie, but due to after-images in our eyes, we cannot perceive...
C. SHORT ANSWER TYPE
7. Answer the following: (a) What is the function of the lacrimal gland and where is it situated in the body? (b) In what two ways is the yellow spot different from the blind spot? (c) Name an...
C. SHORT ANSWER TYPE
6. Given below are certain structures. Write against each their special functional activity. (a) Organ of Corti and …………… (b) Olfactory nerve and ………….. (c) Retina and ………… Solution:- (a) The organ...
C. SHORT ANSWER TYPE
5. Given below are two sets (a) and (b) of five parts in each. Rewrite them in correct sequence. (a) Cochlea, tympanum, auditory canal, ear ossicles, oval window. (b) Conjunctiva, retina, cornea,...
C. SHORT ANSWER TYPE
4. Mention if the following statements are true (T) or false (F). Give reason. (a) Sometimes medicines dropped into the eyes come into the nose and even throat. (b) Ciliary muscles regulate the size...
C. SHORT ANSWER TYPE
3. Mention, where in living organisms are the following located and state their main functions: (a) Fovea centralis (b) Organ of corti Solution:- (a) The fovea centralis, or yellow spot, is located...
C. SHORT ANSWER TYPE
2. State whether the following statements are true (T) or false (F). If false, correct them by changing any one single word in each.(a) Deafness is caused due to rupturing of the pinna. (b)...
C. SHORT ANSWER TYPE
1. Differentiate between members of each of the following pairs with reference to what is asked in brackets. (a) Myopia and hyperopia (cause of the defect) (b) Rods and cones (sensitivity) (c)...
B. VERY SHORT ANSWER TYPE
3. Which one or more of the expressions in column II are appropriate for the items listed in column I? Match the correct pairs – Column I Column II (i) The blind spot (a) colour of the eye (ii) The...
B. VERY SHORT ANSWER TYPE
2. Note the relationship between the first two words and suggest the suitable word/words for the fourth place. (a) Cones: Iodopsim:: Rods: ________. (b) Sound: ear drum:: dynamic balance:...
B. VERY SHORT ANSWER TYPE
1. Name the following:(a) The photosensitive pigment present in the rods of the retina. (b) The part which equalizes the air pressure in the middle and external ear. (c) The ear ossicle attached to...
A. MULTIPLE CHOICE TYPE
(Select the most appropriate option in each case) 4. The region in the eye where the rods and cones are located is the(a) retina (b) cornea (c) choroid (d) sclera Solution:- (a)...
A. MULTIPLE CHOICE TYPE
(Select the most appropriate option in each case) 3. The three parts of human ear contributing in hearing are –(a) cochlea, ear ossicles and tympanum(b) semicircular canals, utriculus and...
A. MULTIPLE CHOICE TYPE
(Select the most appropriate option in each case) 2. Which part of our ear is shaped like a snail shell?(a) Semi-circular canals (b) Cochlea (c) Stapes (d) Eustachian tube Solution:- (b)...
A. MULTIPLE CHOICE TYPE
(Select the most appropriate option in each case). 1. Which part of the eye is grafted in a needy patient from a donated eye? (a) Conjunctiva (b) Cornea (c) Choroid (d) Ciliary muscles Solution:-...
Determine P (E|F) in: A coin is tossed three times, where (i) $E$ : head on third toss, $F$ : heads on first two tosses (ii) $E$ : at least two heads, $\mathrm{F}$ : at most two heads (iii) $\mathrm{E}$ : at most two tails, $\mathrm{F}:$ at least one tail
Solution: The sample space of the given experiment will be: S={HHH, HHT, HTH, THH, HTT, THT, TTH, TTT} (i) Given that, E: head-on third toss And F: heads on first two tossesSo writing the sample...
Two pairs (A and B) of rabbits were crossed as given below:
(a) Can you tell which coat colour (black or white) is dominant? (b) Is the coat colour sex-linked? Answers: (a) The black colour is dominant. (b) No
Make a Punnett square for finding out the proportion of different genotypes in the progeny of a genetic cross between:
(a) A pure tall (TT) pea plant with a pure dwarf (tt) pea plant. (b) Red flower variety of pea (RR) with white flower variety of pea (rr). (a) A pure tall (TT) pea plant with a pure dwarf (tt) pea...
A family consists of two parents and their five children and the pedigree chart shown below shows the inheritance of the trait colour blindness in them.
(a) Who is colour blind in the parents – the Father or the Mother? (b) How many daughters and how many sons have been born in the family? (c) What does the child 1 indicate about this trait? (d) On...
In a certain species of animals, black fur (B) is dominant over brown fur (b). Predict the genotype and phenotype of the offspring, when both parents are ‘Bb’ or have heterozygous black fur.
Given, B refers to black fur; b refers to brown fur. Genotypic ratio = 1BB: 2Bb: 1bb Phenotypic ratio = 3B: 1b
Does the sex of the child depend on the father or is it just a matter of chance? Discuss.
The sex of the baby depends on the type of sperm that fertilizes the egg. The egg contains only one X chromosome, but half of the sperm released into the vagina during coitus carries X and the...
State the three Mendel’s laws of inheritance.
Mendel’s laws of inheritance: 1. Law of Dominance: Of the two comparative characters present, only one is able to express his opinion while the other is still oppressed. Sounds too low. A recurring...
Explain the following terms:
(a) Heterozygous (b) Homozygous (c) Pedigree chart (a) Heterozygous The Heterozygous dominant with different pair is termed as heterozygous. For Example – Many tongue rollers are heterozygous with...
In a certain species of animals, black fur (B) is dominant over brown fur (b). Show the possible ratio of genotypes and phenotypes of the offspring of pure breeding different coloured parents.
Given, B refers to black fur; b refers to brown fur. Then, the genotypic and phenotypic ratio would be: Genotypic ratio = 1BB: 2Bb: 1bb Phenotypic ratio = 3B: 1b
Explain why generally only the male child suffers from colour blindness and not the female?
Color blindness is a disease inherited because the affected people cannot distinguish between certain colors, mostly red and green. Color blindness is more common in men than women. Such defects are...
List any three features of garden pea with their dominant and recessive traits.
CharacterDominant TraitRecessive TraitFlower ColourPurpleWhiteFlower PositionAxillaryTerminalPlant heightTellDwarf
Among lion, tiger and domestic cat, all the three have the same number of 38 chromosomes, yet they have different appearances. How do you account for such differences?
Lion. Tiger and domestic cat have 38 chromosomes. However, genetic factors including physical appearance, body function, behavior, etc., are not just the effects of chromosome numbers, but this is...
Differentiate between:
(a) Genotype and Phenotype (b) Character and Trait (c) Monohybrid and dihybrid cross (phenotypic ratio). (a) Genotype and Phenotype GenotypePhenotypeGenotype is defined as the set of genes which are...
Which one of the following genotypes is homozygous dominant and which one homozygous recessive in regard to tongue rolling: Rr, rr, RR?
Homozygous dominant – RR Homozygous recessive – rr
Name any two genetic diseases in humans.
Colour blindness 2. Haemophilia
A plant with green pods and smooth seeds with genotype Ggss will give rise to the following gametes:
(a) Gg and Ss (b) Gs and ss (c) Gs and gs (d) Gg and gs Answer: (c) Gs and gs
Match the terms in column I with their explanations in column II
Column IColumn IIGeneticsChromosomes similar in size and shapeAutosomesThe alternative forms of a geneRecessive geneStudy of laws of inheritance of charactersAlleleA gene that can express when only...
The 9:3:3:1 dihybrid ratio is due to
(a) segregation (b) crossing over (c) independent assortment (d) homologous pairing Answer: (c) independent assortment
If a pure tall plant is crossed with a pure dwarf plant, then offspring will be
(a) all tall (b) all dwarf (c) 3 tall 1 dwarf (d) 50% tall 50% dwarf Answer: (a) all tall
Which one of the following is the phenotypic monohybrid ratio in F2 generation?
(a) 3 : 1 b) 1 : 2 : 1 c) 2 : 2 d) 1 : 3 Answer: (a) 3 : 1
Given below are three diagrammatic sketches (A, B and C) of one and the same particular phase during mitotic type of cell division.
(a) Identify the phase (b) What is the diploid number of chromosomes shown in them? (c) Identify whether A, B & C are animal cells or plant cell? Answers: (a) Metaphase (b) Four (c) A- Animal...
Shown below are four stages (A, B, C, D) (not in sequence) of a certain kind of cell division.
1. Is it a plant cell or an animal cell? Give two reasons 2. Is it undergoing mitosis or meiosis? 3. What should be the correct sequence of these four stages among themselves? 4. Name the stage that...
Given below is a diagram representing a stage during mitotic cell division. Study it carefully and answer the questions that follow:
(a) Is it a plant cell or an animal cell? Give a reason to support your answer. (b) Identify the stage shown. (c) Name the stage that follows the one shown here. How is that stage identified? (d)...
Given below is a diagram representing a stage during mitotic cell division in an animal cell. Examine it carefully and answer the questions which follow.
(a) Identify the stage. Give one reason in support of your answer. (b) Name the cell organelle that forms the ‘aster’. (c) Name the parts labelled 1, 2 and 3. (d) Name the stage that follows the one...
The diagram given below represents a certain phenomenon which occurs during meiosis. Name and explain the phenomenon by using the terms – homologous chromosomes, chromatids, and crossing-over.
The exchange of chromatids between homologous ones is known as Crossing-over. 1. Chromosome number is divided in half of the gametes so that during the fertilization, the normal number (2n) is...
Draw a labelled diagram to show the metaphase stage of mitosis in an animal cell having ‘6’ chromosomes.
The diagram below represents a stage during cell division. Study the same and then answer the questions that follow:
a. Name the parts labelled 1, 2 and 3. b. Identify the above stage and give a reason to support your answer. c. Mention where in the body this type of cell division occurs. d. Name the stage prior...
The three sketches given below (A, B and C) are intended to represent the replication of DNA. What should be their correct sequence starting with the first and ending with the last?
Answer:
Given below is a schematic diagram of a portion of DNA.
(a) How many strands are shown in the diagram? (b) How many nucleotides have been shown in each strand? (c) Name the parts numbered 1,2,3,4 and 5 respectively. (d) Name the DNA unit constituted by...
Why is meiosis referred to as ‘reductional division’?
Meiosis is a type of cell division that produces sex cells or gametes. It occurs in the reproductive organs (testis and ovary) in humans to produce sperm and ova. In flowering plants, it occurs in...
Name and explain the various stages of the cell cycle.
A cell cycle is a series of events that take place in a cell that leads to the replication of its DNA and subsequent division of the cell to produce two daughter cells. The cell cycle consists of...
Enumerate the various changes that occur in the nucleus of the cell during (a) prophase (b) anaphase of mitotic division.
Prophase: Centrioles began to separate and reached the opposite poles. 2. Chromosomes vary. 3. Chromosomes are already duplicated as paired chromatids. 4. The chromatids are attached to a small...
What are genes?
Genes are the direct sequence of nucleotides in the chromosome, which include specific proteins that express the state of a particular body part. It is the genes that are passed on from one...
What are chromosomes?
When an unrestricted living cell is seen under a bright microscope, its nucleus may appear to contain nothing inside. But when the same cell has the right spots, several structures are visible in...
Mention whether the following statements are true (T) or false (F). Give reason in support of your answer.
(a) As you grow from childhood to adulthood, your skin cells divide only to replace such cells that are lost from the surface. (b) The unfertilized human egg has half the number of chromosomes of...
“Gametes must be produced by meiosis for sexual reproduction”. Why is it so?
When male and female gametes merge during fertilization, a normal number of double chromosomes are rediscovered. This is why gametes should be produced by meiosis for sexual reproduction.
“First meiotic division is the reduction division”. What does the word ‘reduction’ refer to in this statement?
Reduction is the number of chromosomes in the sex cells divided in half such as 23 pairs of chromosomes in humans, only chromosomes are the number one pairs of cells that are passed on to the sex...
State the difference between:
(a) Chromosome and chromatid (b) Centrosome and Centromere (c) Aster and spindle fibres (d) Haploid and diploid (a) Chromosome and chromatid ChromosomeChromatinChromosomes are nucleus that contains...
Correct the following statements if there is any mistake.
1. The four nitrogenous bases in the DNA are Guanine, Thiamine, Adrenaline and Cytosine. 2. Genes are specific sequences of bases on a chromosome. 3. A nucleotide is composed of a sulphate, a sugar...
What are the rungs of the “DNA ladder” made of?
The rungs of the “DNA ladder” is made up of, Adenine (A) 2. Guanine (G) 3. Cytosine (C) 4. Thymine (T).
What is the difference between chromatin fibre and chromosome?
ChromosomeChromatinChromosomes are nucleus that contains cell’s DNA which is arranged into discrete units.Chromatin is a chromosome that contains one single long DNA molecule connected with many...
4. Fill in the blanks
1. DNA replicates in the …………. of the cell cycle. 2. Mitosis occurs in our …………. cells. 3. Mitosis produces two daughter cells, whereas meiosis produces ………… daughter cells. 4. Meiosis occurs only...
Match the events given in column A with the phase in mitotic cell division in column B
COLUMN ACOLUMN BChromosomes become arranged in a horizontal plane at the equatorAnaphaseDaughter chromosomes move to the opposite poles of a spindleProphaseChromosomes become visible as fine long...
Imagine one cell (A) has undergone one mitotic division and another cell (B) has completed its meiotic division. How many cells would the two produce?
Cell A produces 2 cells Cell B produces 4 cells
Name the following:
1. The repeating components of each DNA strand lengthwise. 2. The complex structure consisting of DNA strand and a core of histones. 3. The type of bond which joins the complementary nitrogenous...
Synthesis phase in the cell cycle is called so for the synthesis of more of
(a) RNA (b) RNA and proteins (c) DNA (d) Glucose Answer: (c) DNA
In which one of the following options the stages of mitosis have been given in correct sequence?
(a) Prophase, metaphase, telophase, anaphase (b) Prophase, metaphase, anaphase, telophase (c) Anaphase, telophase, prophase, metaphase (d) Telophase, anaphase, prophase, metaphase Answer: (b)...
3. The number of chromosomes in a certain type of cell division is halved. This kind of cell division occurs in
(a) only testis (b) only ovary (c) both ovary and testis (d) all body cells Answer: (c) both ovary and testis
The term “chromosomes” literally means
(a) Inherited bodies (b) Twisted threads (c) Colored bodies (d) Shining threads Answers: (c) Colored bodies
The chromatin material is formed of
(a) DNA only (b) DNA and Histones (c) Histones only (d) Nucleotides Answer: (b) DNA and Histones
Shown Below are some of the cell organelles.
Can you identify these? The given cells are, 1.Mitochondria which is the power house of the cell. 2.Centrosome which is present in the animal cell alone and contains one or two centrioles. 3.Golgi...