Ans 1. The xylem transports water and mineral salts. The phloem transports sugars away from the leaf.

 

Ans 2. - Long and narrow

            - Water and minerals obtained through diffusion

            - Found in only plants

            - Doesn’t contain chlorophyll. 

 

Ans 3. - Not dead

            - Hollow

            - Attached with a companion cell (which contains nucleus)

            - Doesn’t contain lignin

            - Diffusion and active transport

            - Glucose and minerals transported. 

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Ans 4. - Contains haemoglobin

            - No nucleus,

            - Increased surface area to volume ratio (SA:V)

            - Bi-concave shape

            - Made in bone marrow

            - Cannot divide/replicate once specialized

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Ans 5. Nutrition, respiration, excretion, movement, reproduction, growth, sensitivity, adaptability

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Ans 6. Smallest unit of life capable of living in an environment free of life. 

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Ans 7. A catalyst is a substance which can alter or speed up a chemical reaction without being used up in the reaction itself. Catalysts help speed up the reaction at a lower temperature. 

 

Ans 8. It is the combined effect of respiration, evaporation, and photosynthesis because of which plants lose water vapor from their leaves. The bigger the plant, the more effect of transpiration. 

 

Ans 9.  Factors: Wind, temperature, light, humidity 

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Ans 10. Movement of food substances in the phloem 

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Ans 11. 

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Ans 12. 

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Ans 13. Systole - contraction of ventricle 

              Diastole - relaxation of ventricle 

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Ans 14. It is the energy required to start a chemical reaction 

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Ans 15. Carbohydrases, proteases and lipases 

 

Ans 16. A substrate is the substance on which an enzyme acts.

             Active sites are depressions on the surface of the enzymes where substrates fit. 

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Ans 17. Amylase acts on starch 

              Maltase acts on maltose 

              Protease acts on protein 

              Lipase acts on fats 

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Ans 18. When wounded, thrombokinase works on prothrombin in the presence of calcium ions to form thrombin. Thrombin (another enzyme) then turns fibrinogen into fibrin. Fibrin then entangles blood cells, makes a clot, and seals the wound.

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Ans 19. Monocots: 

- Floral organs in multiples of 3s 

- Parallel veins in leaves 

- Random distribution of vascular tissue 

- One cotyledon 

- Adventitious roots 

    Dicots: 

- Floral organs in multiples of 4s and 5s,

- Branched veins

- Fixed ring pattern of vascular tissue

- Two cotyledons

- Branched roots

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Ans 20. Auxin: Plant growth 

              Absisic acid: Transpiration rate

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Ans 21. Directional external stimuli that plants respond to. E.g. negative tropism is opposite of gravity, whereas positive tropism is towards the light.

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Ans 22.  - A solvent for chemical reactions

               - Key component of tissues

               - Controls body temperature

               - Transport dissolved substances

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Ans 23. Hormones are biological chemicals which are synthesized inside your body that regulate biological systems. 

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Ans 24. Weight gain, lack of energy, depression, appetite loss, feeling cold and goitre

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Ans 25. - Sugar called deoxyribose

              - Phosphate group

              - Bases (Adenine, Cytosine, Guanine, Thymine) 

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Ans 26. Endocrine System: Ductless glands, direct into bloodstream

              Exocrine System: With ducts

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Ans 27. Insulin – glucose to glycogen

              Glucagon – glycogen to glucose

              Thyroxin – regulates metabolic rate and body temperature

              Leptin – feel hungry or full

              Melatonin – circadian cycles

              Testosterone-  male sex hormone

              Estrogen/Progesterone – female sex hormone.  

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Ans 28. Ovary, filament, anther, stigma, style, sepal, petal

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Ans 29. 1) Fragmentation/regeneration

              2) Binary and multiple fission

              3) Parthenogenesis

              4) Budding

              5) Sporulation

              6) Cloning

              7) Vegetative propagation

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Ans 30. Gamete – Reproductive cells that contain half the number of chromosomes as the normal body cells.

              Diploid – 46 chromatids (2n)

              Haploid – 23 chromatids (n)

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Ans 31. The net movement of free water particles from an area of higher water potential to an area of lower water potential across a concentration gradient / selectively permeable membrane. 

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Ans 32. Cortex, phloem, cambium, pith, xylem and epidermis

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Ans 33. Surface are is how much material the cell can take in. The volume is the amount of material a cell needs to survive. 

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Ans 34. Molecules/atoms are unpredictable; particles have no path; they keep moving randomly after equilibrium

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Ans 35. Crenation – cell shrinks and spikes appear on cell surface membrane (hypertonic solution)

              Plasmolysis – cell shrinks as surrounding cell takes in water (hypertonic solution)

              Cellysis – cell bursts as it accepts water from solution (hypotonic solution)

              Turgidity – water accepted by cell, vacuole pushes on cell wall, does no burst due to cell wall (hypotonic solution)

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Ans 36. Isotonic – solute and water potential are equal

              Hypotonic – solute is less than water potential (less concentrated)

              Hypertonic – solute is more than water potential (more concentrated)

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Ans 37.  - One parent required

               - Fusion of gametes not required

               - Beneficial qualities of plant passed down to offspring

               - Faster method

               - Colonize areas rapidly

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Ans 38. When fertilization occurs, and the nucleus of the male gamete fuses with the nucleus of the female gamete

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Ans 39. Allele – Different versions of the same gene

              Homozygous – two identical alleles for a particular characteristic in each cell (BB/bb)

              Heterozygous – two different alleles for a particular characteristic in each cell (Bb)

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Ans 40. Substitution, insertion, deletion, inversion

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Ans 41. Genes – basic units of inheritance in a living organism (sequence of bases that control the formation of a single polypeptide).

              Transcription – process by which the genetic code is copied from DNA by mRNA.

              Translation – mRNA travels from nucleus to cytoplasm where it is ‘decoded’ and read by ribosomes to synthesize protein.

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Ans 42. 1) Substance for respiration

              2) Form supporting structures

              3) Converted into other organic compounds

              4) Formation of nucleic acids

              5) Synthesize lubricants

              6) Synthesize nectar in some flowers

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Ans 43.  Stomata opens – sunlight/high photosynthesis rate and reduced carbon dioxide concentration

               Stomata closes – water shortage, absisic acid produced, darkness

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Ans 44. It is the temperature at which a specific cell functions. Cells would be permanently damaged if there is more heat than the optimum temperature.

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Ans 45. Proteins that function as biological catalysts. They lower activation energy. 

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Ans 46. - Makes chemical energy available to animals and other organisms in the food web

              - Removes CO2 and provides O2

              - Energy stored in fossil fuels

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Ans 47. Peristalsis is the rhythmic muscular contractions in the wall of the alimentary canal.

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Ans 48. - Surface area through villi and micro villi

              - Thin membrane

              - Concentration gradient through blood

              - Very long so ample time given

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Ans 49. Process in which light energy is absorbed by chlorophyll is transformed into chemical energy, which is then used to synthesize carbohydrates from water and carbon dioxide. Oxygen is released during the process.

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Ans 50. Light energy is used to split water molecules into oxygen and hydrogen atoms

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Ans 51. 6CO2 + 6H2O            C6H12O6 + 6O2 

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Ans 52. - Larger than red blood cells

              - Colorless

              - Don’t contain haemoglobin

              - Irregular shape,

              - Has a nucleus

              - Can move and change shape

              - Two types – lymphocytes and phagocytes

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Ans 53. Eythrocytes 

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Ans 54. 1) Long hollow tubes from root to leaves

              2) Narrow and no cross walls in lumen

              3) No protoplasm

              4) Walls thickened with lignin for support

              5) Substance travel in one direction only

              6) Filters

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Ans 55. Catabolism – rate of breaking down material

              Anabolism – rate of utilizing broken down material.

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Ans 56. - Petiole

              - Thin and broad lamina

              - Waxy cuticle on epidermis

              - Stomata present

              - Chloroplast in all mesophyll cells

              - Chloroplast in palisade mesophyll

              - Interconnecting system of air spaces in spongy mesophyll

              - Veins connecting xylem and phloem

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Ans 57. Dependent – thylakoid membrane and stack

              Independent – stomata

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Ans 58. Light intensity, concentration of CO2 & temperature

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Ans 59. 1) Water (70 % of body, 90% of blood volume)   

              2) Body temp between 36 and 38 C

              3) Blood pH between 7.35 and 7.45 pH

              4) CO2 concentration must be less than O2 concentration

              5) Blood glucose between 80 mgdl^-1 and 110 mgdl^-1

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Ans 60. Negative : Temperature, pH, glucose in blood, testosterone, estrogen, progesterone

              Positve: Blood clotting 

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Ans 61. The net movement of particles from an area of higher concentration to an area of lower concentration across a concentration gradient. 

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Ans 62. The net movement of particles from an area of lower concentration to an area of higher concentration against a concentration gradient. 

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Ans 63. - Source/store of energy

              - Insulating material

              - Solvent for fat soluble materials and vitamins

              - Reduce water loss from skin surface

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Ans 64. 1) Insouluble in water

             2) Large molecules, thus cannot diffuse through cell membranes

             3) Can be easily hydrolysed to glucose

             4) Compact shape and occupy less space

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Ans 65. Exhaled air, urine, faeces, and sweating.

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Ans 66. 

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Ans 67. Glycogen. It is the main store of glucose in animals. Animals cannot make or store starch in their bodies.

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Ans 68. Nutrients enter faster, heat is lost faster, and waste leaves faster

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Ans 69. Cell division takes place, producing two smaller and more efficient cells

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Ans 70. A chemical reaction in which two simple molecules are joined together to form a larger molecule with the removal of one molecule of water. 

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Ans 71. Epithelial, connective, muscle, neural

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Ans 72. Voluntary and involuntary muscle systems

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Ans 73. A reaction in which a water molecule is needed to break a complex molecule into simpler smaller molecules.

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Ans 74. In adipose tissues

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Ans 75. 1) Shallow roots – near surface, long branches, collect run off water and nutrients near surface 

              2) Branching roots – increase sa: v, increased nutrient absorption

              3) Dicot tap roots – deeper into soil to absorb water and mineral ions, apical meristems present

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Ans 76. - Growth and repair of worn out body cells

             - Synthesis of enzymes and hormones

             - Formation of antibodies

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Ans 77.  C6H12O6 + 6O2 --> 6CO2 + 6H2O + Energy

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Ans 78. Too much polyunsaturated fats and cholesterol in diet

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Ans 79. Unsaturated fats in the diet

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Ans 80. Glucose: C6H12O6

             Sucrose: C12H22O11

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Ans 81. The hepatic portal vein transports nutrients from the small intestine to the liver

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Ans 82. Plasma is a complex mixture containing:

- 90% water

- Fibrinogen, prothrombin, and antibodies

- Dissolved mineral salts (hydrogencarbonates, chlorides,sulfates of  calcium and phosphate, sodium and potassium)

- Food substances (glucose, amino acids, fats)

- Excretory substances (urea, uric acid, creatinine)

- Hormones.

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Ans 83. - Cuticle

              - Upper epidermis

              - Palisade mesophyll

              - Vascular bundles

             - Spongy mesophyll

             - Lower epidermis

             - Guard cell and stomata

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Ans 84. Monosaccharides – glucose, fructose, galactose

              Disaccharides – maltose, sucrose, lactose

              Polysaccharides – starch ,glycogen, cellulose

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Ans 85. Milk sugars in mammals