Sieve Cells	Sieve Tubes
Have no companion cells	Have companion cells always
The sieve areas do not form sieve plates	The sieve areas are confined to sieve plates

The photoperiod required to induce flowering is called critical day length

(i) Nematodes of phylum nematode are triploblastic and bilaterians.
(ii) Coelom of these animals is loosely found with mesenchyme.
(iii) So coelom appears to be false hence it is called as pseudocoelom.
(iv) Eg: Ascaris (Round worm)
Anchylostoma (Hook worm)
Enterobious (Pin/sear worm)
Wucheraria (Filarial worm)

1. When the flower, contains only one of the essential whorls is called Imperfect flower
2. It is of two types:
i) Staminate flowers: Flowers only with androecium alone are called staminate flowers.
ii) Pistillate flowers: Flowers with only gynoecium are called pistillate flowers.

The three odoured plastids are Chloroplast, Phaeoplast, Rhodoplast.

(i) Mineral deficiency of plant A is due to Molybdenum
(ii) Mineral deficiency of plant B is due to Zinc

Peculiarity characters of ducks:
1. The body is fully covered with oily feathers.
2. They have a layer of fat under their skin which prevents it from getting wet.
3. They lay eggs at night or in the morning.
4. The ducks feed on rice bran, kitchen wastes, waste fishes and snails.

Economic importance of prawn:
(i) Prawn is a very tasty proteinaceous food.
(ii) Economic growth can be achieved by prawn at a low cost.
(iii) It is profitable to cultivate prawns in fresh water at a low cost.
(iv) By Exporting prawns can also bring a lot of foreign currency to the country.

Skull bones.

Renal artery supplies (arterial) oxygenated blood and renal vein carries out deoxygenated blood (venous) from kidneys.

Sensory neurons of the parasympathetic autonomic nervous system.

They are a type of WBC (granulocytes).
1. Basophils secrete substances such as heparin, serotonin, and histamines.
2. They are also involved in inflammatory reactions.

(i) The head is small, triangular and lies at right angle to the longitudinal axis of the body.
(ii) The mouth parts are directed downwards so it is hypognathous.

Male frog attracts female frog by amplifying its croaking sound during breeding season.

In pycnoxylic the secondary growth in wood is compact with narrow medullary ray. Eg. Pinus

Leopold (1961) has recognised four types of senescence:
1. Overall senescence
2. Top senescence
3. Deciduous senescence
4. Progressive senescence

(a) Cinnamon - Spice got from the bark of the tree. Eg: Cinnamomum.
(b) Rubber - Got from the latex vessels of the inner bark of Hevea brasiliensis.

Absorbed substances are transported through blood and lymph to the liver through the hepatic portal system. From the liver, nutrients are transported to all other regions of the body for utilization. All the body tissues utilize the absorbed substance for their activities and incorporate into their protoplasm, this process is called assimilation.

Certain substances present in the cells may react with the enzyme and lower the rate of reaction. These substances are called inhibitors. It is of two types competitive and non-competitive

1. Presence of nucleic acid and protein.
2. Capable of mutation
3. Ability to multiply within living cells.
4. Able to infect and cause diseases in living beings.
5. Show irritability.
6. Host -specific

The transmission of impulse involves two main phases; Resting membrane potential and Action membrane potential.
Resting membrane Potential: The electrical potential difference across the plasma membrane of a resting neuron is called the resting potential during which the interior of the cell is negative due to greater efflux of K⁺ outside the cell than Na⁺ influx into the cell. 
Action membrane potential: An action potential occurs when a neuron sends information down an axon, away from the cell body. It includes following phases, depolarization, repolarisation and hypo polarization.

(a) Urine
(b) Glomerular filtrate
(c) Urinary bladder
(d) afferent and efferent arterioles and venules of renel artery and renel vein.
(e) Excretion
(f) Bowman's capsule
(g) Ureters
(h) Micturition
(i) Balance of electrolytes minerals and organics
(j) excretory system
(k) micturition
(l) glucose, amino acid and liquids

S.No.	Aggregate fruit	Multiple fruit
1	Aggregate fruits develop from a single fl ower having an apocarpous pistil. each of the free carpel develops into a simple fruitlet. A collection of simple fruitlets makes an Aggregate fruit. An individual ovary develops into a drupe, achene, follicle or berry	A Multiple or composite fruit develops from the whole infl orescence along with its peduncle on which they are borne
2	Eg: Polyalthia	Eg: Pineapple

Photosynthesis in Plants		Bacterial Photosynthesis
1.	Cyclic and Non-Cyclic phosphorylation takes place	Only Cyclic Phosphorylation takes place
2.	Photosystem I and II involved	Photosystem I only involved
3.	The electron donor is water	The electron donor is H2S
4.	Oxygen is evolved	Oxygen is not evolved
5.	Reaction centers are P700 and P680	The reaction center is P890
6.	The reducing agent is NADPH + H+	The reducing agent is NADH + H+
7.	PAR is 400 to 700 nm	PAR is above 700 nm
8.	Chlorophyll, Carotenoid, and Xanthophyll	Bacteria chlorophyll and Bacteria viridin
9.	Photosynthetic apparatus -  chloroplast	It is chlorophyll and chromatophores.

Habit:
Perennial herb with bulb.
Root:
Fibrous adventitious root system
Stem:
Underground bulb
Leaf:
a cluster of radical leaves emerges from the underground bulb, cylindrical and fleshy having sheathy leaf bases with parallel venation.
Inflorescence:
Scapigerousi.e. the inflorescence axis (peduncle) arising from the ground bearing a cluster of flowers at its apex. Pedicels are of equal length, arising from the apex of the peduncle which brings all flowers at the same level.
Flower:
Small, white, bracteate, ebrcteolate, pedicellate, complete, trimerous, actinomorphic and hypogynous. Flowers are protandrous.
Perianth:
Tepals 6, white,arranged in two whorls of three each, syntepalous showing valvate aestivation.
Androecium:
Stamens 6, arranged in two whorls of three each, epitepalous, apostamenous free and opposite to tepals. Anthers dithecous, basifixed, introse, and dehiscing longitudinally.
Gynoecium: Tricarpeltary and syncarpous. Ovary superior, trilocular with two ovules in each locule on axile placentation. Style simple, slender with simple stigma.
Fruit:
A loculicidal capsule.
Seed:
Endospermous
Floral Formula:

Rh factor compatibility is also checked before blood transfusion. When a pregnant women is Rh^- and the foetus is Rh⁺ incompatibility (mismatch) is observed. During the first pregnancy, the Rh^- antigens of the foetus does not get exposed to the mother's blood as both their blood are separated by placenta. However, small amount of the foetal antigen becomes exposed to the mother's blood during the birth of the first child. The mother's blood starts to synthesize D antibodies. But during subsequent pregnancies the Rh antibodies from the mother (Rh^-) enters the foetal circulation and destroys the foetal RBCs. This becomes fatal to the foetus because the child suffers from anaemia and jaundice. This condition is called erythroblastosis foetalis. This condition can be avoided by administration of anti D antibodies (Rhocum) to the mother immediately after the first child birth.

Photoperiodic induction
1) An appropriate photoperiod in 24 hours cycle constitutes one inductive cycle. Plants may require one or more inductive cycles for flowering.
2) The phenomenon of conversion of leaf primordia into flower primordia under the influence of suitable inductive cycles is called photoperiodic induction.
Example: Xanthium (SDP) - 1 inductive cycle and Plantago (LDP)- 25 inductive cycles.
Site of Photoinductive perception
1) Photoperiodic stimulus is perceived by the leaves.
2) Floral hormone is synthesised in leaves and translocated to the apical tip to promote flowering.
3) This can be explained by a simple experiment on Cocklebur (Xanthium pensylvanicum), a short day plant.
4) Usually Xanthium will flower under short day conditions. If the plant is defoliated and kept under short day conditions it will not flower.
5) Flowering will occur even when all the leaves are removed except one leaf.
6) If a cocklebur plant is defoliated and kept under long day conditions, it will not flower.
7) If one of its leaves is exposed to short day condition and rest are in long day condition, flowering will occur.

Structure of thyroid gland:
Thyroid gland is the largest endocrine gland in the body.


1. It is a butterfly shaped, bilobed gland located below the larynx on either side of upper trachea.
2. The two lateral lobes are connected by a median tissue mass called isthmus.
3. Each lobe is made up of many lobules. The lobules consist of follicles called acini.
4. Each acinus is lined with glandular, cuboidal or squamous epithelial cells. The lumen of acinus is filled with colloid, a thick glycoprotein mixture consisting of thyroglobulin molecules.
5. It secretes two hormones namely tri-iodothyronine [T₃] and thyroxine or tetra- iodothyronine [T₄].
6. The parafollicular cells or 'C' cells of thyroid gland secrete a hormone called thyrocalcitonin.
7. Iodine is essential for the normal synthesis of thyroid hormone.
8. Thyroid hormones shows a negative feedback effect on the hypothalamus and pituitary.

(i) The process of elimination of nitrogenous wastes, salt and water balance from the body is called excretion.
(ii) This system consists of a paired kidneys, ureters, urinary bladder and cloaca.
(iii) Kidneys are dark red, long, flat organs situated on either sides of the vertebral column.
(iv) Kidneys are mesonephric type.
(v) The functional excretory units of kidneys are nephrons.
(vi) Nephrons separate nitrogenous wastes from the blood and excrete urea so frogs are ureotelic.
(vii) A paired long ureter emerges from the kidneys and opens into the cloaca.
(viii) A thin walled unpaired urinary bladder is present ventral to the rectum.
(ix) Rectum opens into the cloaca.

1. The fungi belonging to this group lack sexual reproduction and are called imperfect fungi.
2. A large number of species live as saprophytes in soil and many are plant and animal parasites.
3. Asexual reproduction takes place by the production of conidia, chlamydospores, budding, oidia etc.,
4. Conidia are also produced in special structures I called Pycnidium, Acervulus, Sporodochium: and Synnemata.
5. Parasexual cycle operates in this group of fungi. This brings genetic variation among the species.