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In highly organised plants xylem and phloem are the components of the transport system.

Xylem and phloem.

Pedicel: The stalk of the flower which is for the support is called pedicel.

(b) mitochondria.

Correct option  (D) Z

Explanation: 

 The path followed by nerve impulse in a reflex action is called reflex arc. The given figure shows reflex arc, where 'W' is effector (muscle in arm), 'X' is sensory neuron, 'Y' is motor neuron and 'Z' is interneuron (relay neuron). When our hand accidently touches a hot object, it is sensed by the receptors present in the skin of hand. This triggers nerve impulse in sensory neuron which is passed on to the intereuron in the spiral cord. The interneuron further passes on this impulse to the motor neuron. The motor neuron transmits the instruction to the effector in muscles of arm. The arm muscle contracts and pulls our hand away from the hot object.

The part of the diagram labeled as b will have the highest blood pressure in the whole circulatory system. The part labeled as b represents aorta. It is the largest artery which supplies the oxygenated blood from the left ventricle of heart to the body tissues. It has the highest pressure as the left ventricle has to pump the blood to all the body parts.

Small intestine in the Alimentary canal.

The final product produced after digestion of carbohydrates is glucose and of proteins is amino acids.

Carbohydrates: Glucose

Proteins: Amino acid

Fats: Glycerol + Fatty acid

• Photosynthesis is a process by which plants produce their own food by utilizing sunlight, CO₂ and water. 
• CO₂ and water are converted to carbohydrates with the evolution of oxygen.
• Photosynthesis reaction can be given by following reaction.

\(6CO_2+6H_2O\overset{Sunlight energy}\rightarrow C_6H_{12}O_6+6O_2\)

Process of Photosynthesis is divided into 4 processes 

1. Absorption of light energy by chlorophyll 

2. Conversion of light energy into chemical energy 

3. Splitting of water molecules into Hydrogen and Oxygen 

4. Reduction of CO₂ to produce carbohydrates

Carbohydrate Digestion 

• Digestion of cabohydrates starts with buccal cavity where salivary enzymes breaks down the starch into simple sugar molecules. 
• Other sugar molecules are breakdown to glucose in small intestine. 

Protein digestion 

• Proteins are partially digested by pepsin secreted by gastric glands present in the stomach. 
• Then Pancreatic juice secrets trypsin and chymotrypsin enzymes in small intestine where complete digestion of proteins takes place. 

Fat Digestion 

• Fats are digested in small intestine.
• Bile juice present in the liver emulsifies the fat which breaks fats into small globules.
• These small fat globules are converted into glycerol and fatty acids by Lipase enzyme.

Digestion of carbohydrates: Starch is digested in the mouth by salivary amylase. Other forms of carbohydrates are digested in the small intestine. 

Starch + Salivary Amylase → Sucrose 

Maltose + Maltase → Glucose 

Lactose + Lactase → Glucose + Galactose 

Digestion of Proteins: Partial digestion of protein takes place in the stomach by gastric enzyme pepsin. Further digestion of protein happens in the small intestine. 

Protein + Pepsin → Peptone + Proteose 

(Protein + Peptone + Proteose) + (trypsin + chymotrypsin) → Dipeptides 

Digestion of Fat: Fat is at first emulsified by bile and then its digestion happens in the small intestine. 

Fat + Lipase → Fatty acids + Glycerol

HCI of gastric juice disinfects the food and acidifies it for the proper functioning of the proteolytic enzyme pepsin.

(i) Help in mixing the food thoroughly with more digestive juice by peristalsis.

(ii) Creates an acidic medium which facilitates the action of the enzyme pepsin.

(iii) Protects the inner lining of the stomach from the action of the acid.

a) Hydrochloric acid: It makes the medium of gastric juice acidic so that the enzyme pepsin  can digest the proteins properly and also kills any bacteria that might have entered the  stomach with food.  

(b) Enzymes help in the breaking down of complex organic food materials into simpler forms.

Androecium and gynoecium.

(1) The structural unit of sexual reproduction in plants is flower. There are total four floral whorls. Of these, two are accessory floral whorls while two are essential floral whorls.

(2) Calyx and corolla are accessory whorls. They are protective in nature.

(3) Members of calyx are known as sepals. They are usually green in colour. They protect the inner whorls.

(4) The members of corolla are called petals. They can be of different colours.

(5) Androecium and gynoecium are essential whorls as they participate in sexual reproduction.

(6) The male whorl androecium is made up of stamens. Each stamen has a filament with anther located at the upper end. In the anther there are four locules. Inside the locules the meiosis takes place forming pollen grains. During suitable time, the pollen grains are released from anther lobes.

(7) Gynoecium is made up of carpels, either in separate form or are united. Each carpel is formed of ovary at the basal end hollow ‘style’ and the stigma at the tip of style. There are one or many ovules inside the ovary.

(8) In bisexual flowers both androecium and gynoecium are located in the same flower, e.g. Hibiscus.

(9) In unisexual flowers, androecium is present in male flowers and gynoecium is present in the female flowers, e.g. Papaya.

In fission, the parent cell divides into two. This nucleus and cytoplasm, both are divided. Thus, parent cell does not exist any longer, it is converted into new cells.

Seminal vesicles, Prostate gland, Cowper’s or bulbourethral glands.

i. Follicle stimulating hormone and ICSH or Luteinizing hormone secreted by pituitary gland, testosterone secreted by testis.

ii. Estrogen and progesterone.

iii. Monozygotic twins, Siamese twins and Dizygotic twins.

iv. Gonorrhea and Syphilis.

v. Copper T, condoms, oral contraceptive pills.

(a) True.

(b) False.

(a) False.

(b) True.

(c) False

(a) Oxygen.

(b) Carbon dioxide.

• Mucus prevent inner lining of stomach from HCl.
• Mucus prevents drying of inner lining of the stomach. Mucus helps in easy movement of food particles through digestive system.
• If mucus is not secreted food will not easily moved through digestive system. 
• HCl will damage the stomach lining and the digestion process will not take place.

Lungs is attached to the two bronchi. 

The urea is formed by the urea-cycle in the liver, and not in the kidneys. The blood vessel coming out from the kidney will contain the lowest concentration of urea (although kidneys contain only a small amount of urea to maintain osmolarity). And the blood vessel coming out from the liver will contain the highest concentration of urea.

The deoxygenated blood is collected from the body tissues through the veins which further combine to form vena cava. This vena cava pours deoxygenated blood collected from the body tissues into the right auricle of heart. From right auricle it goes to right ventricle and from here the blood is pumped into the pulmonary artery which takes the deoxygenated blood from heart to the lungs. In the alveoli of lungs the blood is oxygenated. This oxygenated blood is pumped into the pulmonary veins which pours the blood into the left auricle. From here the oxygenated blood is poured into the left ventricle. The left ventricle pushes the blood into the aorta which pumps the oxygenated blood into the body tissues and supply oxygen through the tissues for various body functions.

i. (b) testis

ii. (b) Y

iii. There is no similar gland in male and female reproductive system. There may be some homologies but there is no similarity.

iv. (c) uterus

v. (a) Asexual

vi. (b) fragmentation

vii. (a) meiosis

(B) (i) and (iii) only 

Correct option  (D) Bowman's capsule, Glomerulus

Explanation: 

The upper cup shaped end of a nephron is called Bowman's capsule. lt contains glomerulus which is a group of blood capillaries.

Correct option is: (b) Testosterone

NAD → Nicotinamide Adenine Dinucleotide and FAD Flavin Adenine Dinucleotide.

Correct option  (C) Y receives blood from lungs. 

Explanation: 

 ln the given figure, X is right atrium that receives deoxygenated blood from body, P is right ventricle that passes deoxygenated blood to lung for oxygenation. Yis left atrium that receives oxygenated blood from lungs. Q is left ventricle that supplies oxygenated blood to body.

• Carbohydrates are converted to glucose after the process of digestion is completed. The oxidation of glucose for releasing energy is called glycolysis which takes place in cytoplasm.
• Glycolysis can occur in presence of oxygen or without oxygen too. The first type of glycolysis takes place in aerobic respiration and the second type is in anaerobic respiration.
• In aerobic respiration, there is step-wise oxidation of glucose molecule forming two molecules each of pyruvic acid, ATP, NADH and water.
• Later the pyruvic acid formed in this process is converted into molecules of AcetylCoenzyme-A along with two molecules of NADH₂ and two molecules of CO₂.
• During anaerobic respiration along with glycolysis there is fermentation too. This is incomplete oxidation of glucose and thus it results in formation of lesser energy.
• The process of glycolysis was discovered by Gustav Embden, Otto Meyerhof, and Jacob Parnas. Therefore, in their honour, glycolysis is also called as Embden-Meyerhof-Parnas pathway (EMP pathway). For the discovery they had performed experiments on muscles.

The process of glycolysis takes place m the cytoplasm of the cell. One molecule of glucose is gradually oxidized step by step forming two molecules of each pyruvic acid, ATP, NADH and water. Of these, pyruvate or pyruvic acid takes part in the further reactions.

(1) Sexual reproduction occurs due to two different gametes. One male gamete is from father while the other female gamete is from mother.

(2) Both the gametes are produced by meiosis.

(3) When the gametes unite it is called process of fertilization which produces diploid zygote.

(4) Due to the chromosomes of parents, their DNA pass to the next generation through such fertilization. Therefore, the characters of newborn show similarities with parents.

(1) If a piece of bread is kept in moist container we can see growth of fungus on it.

(2) Fungi belonging to species Mucor is seen. It has filamentous body and sporangia. Sporangia burst open to spread spores. It has saprophytic mode of nutrition as it devoid of chlorophyll.

Cellular respiration: Oxidation of glucose and other food components which takes place inside the cell in presence or absence of oxygen, is known as cellular respiration.

Correct option  (B) Ethanol

Explanation: 

The anaerobic respiration is also called fermentation. lt occurs in absence of oxygen and produces ethyl alcohol or ethanol and CO₂.

Molecules of CO₂, H₂O, NADH₂, FADH₂ and ATP.

Mammals and birds are warm-blooded animals. They constantly use energy to maintain their body temperature. They have higher energy needs and so they require more oxygen to produce energy. Thus, it is important that their oxygenated blood does not get mixed up with deoxygenated blood.

The difference between aquatic and terrestrial respiration is as follows:

• After pollination the pollen grains drop on the sticky stigma of the flower.
• They germinate here producing two male gametes and a long pollen tube.
• The male gametes travel through the pollen tube till they reach the embryo sac.
• Here the male gametes are released by bursting the pollen tube. One male gamete unites with the egg cell to form zygote while the second male gamete unites with two polar nuclei forming endosperm.
• In this way because two nuclei participate in the fertilization process, therefore it is called double fertilization.

• Flower produces male and female gametes.
• For this purpose there are essential whorls of androecium and gynoecium.
• The double fertilization also takes place in flower.
• Therefore, flower is called the structural unit of sexual reproduction in plants.

1. When glucose is completely oxidized in aerobic cellular respiration, it produces 38 molecules of ATP.

2. In cellular respiration, three processes take place one after the other, these are glycolysis, Krebs cycle and electron transport chain reactions.

3. In absence of oxygen only glycolysis can occur but further two reactions will not take place.

4. If glycolysis occurs in absence of oxygen, it produces alcohol.

5. By anaerobic glycolysis only two molecules of ATP are produced.

6. This results in less energy supply to the body. Therefore, oxygen is necessary for complete oxidation of glucose.

Fermentation: Conversion of pyruvic acid produced in the process of glycolysis into other organic acids or alcohol with the help of some enzymes is called fermentation.

Gluconeogenesis: Formation of glucose through non-carbohydrate sources such a protein is called gluconeogenesis.

Glycolysis: The process occurring in the cell where a molecule of glucose is oxidized in step by step process forming two molecules of each of pyruvic acid, ATP, NADH₂ and water, is called glycolysis.

The organism that lives in water such as a fish obtains oxygen for respiration which is dissolved in water. Whereas the terrestrial organisms take in oxygen directly from the air. Since the amount of oxygen dissolved in water is fairly low as compared to the amount of oxygen in the air, breathing rate in aquatic organisms is much faster than terrestrial organisms.