Passing Package
BIOLOGY
LIFE PROCESSES
→ Autotrophic nutrition
★ organisms prepare their own food
★ Eg :- all green plants and some bacteria.
→ Heterotrophic nutrition
★ organisms get their food directly or indirectly from plants.
★ Eg :- all animals, fungi and some bacteria.
→ Photosynthesis
Food preparation process in plants using CO2, water, sunlight and chlorophyll.
→ Steps of Photosynthesis:
(i) Absorption of light energy by chlorophyll.
(ii) light energy → chemical energy and water molecules → hydrogen and oxygen.
(iii) Reduction of carbon dioxide to carbohydrates.
→Aerobic respiration:
★ Presence of oxygen
★ More energy released
★ Produce CO2 + H2O + Energy
★ Ex: Plants and Animal
→ Anaerobic respiration:
★ Absence of oxygen
★ Less energy released
★ Produce Ethanol + CO2 + Energy
★ Ex: Yeast
→ Glucose breakdown:
→ Alveoli:
Increase the surface area for gaseous exchange.
→ Stomach functions
★ Gastric glands release hydrochloric acid, pepsin and mucus.
★ Hydrochloric acid helps in action of pepsin.
★ Pepsin digests protein.
→Small intestine functions
★ Small intestine is the site of complete digestion of proteins, carbohydrates and fats.
★ Enzymes in the intestinal juice convert
- proteins into amino acids,
- carbohydrates into glucose
- fats into fatty acids and glycerol.
★ Digested food is absorbed by the villi.
→ Villi:
★ Finger-like projections called villi.
★ It absorb digested food.
→ Digestive enzymes
Amylase: Breakdown starch
Trypsin : Breakdown proteins
Lipase : Breakdown fats
Pepsin: Breakdown proteins
→ Double circulation
Blood flow through heart twice.
Advantages:
★ Suply more oxygen to body tissue
★ Produce more energy to maintain constant body temperature.
→Blood vessels:
➤ Arteries :
★ Carry oxygenated blood
★ Thick wall
★ No valve
★ High blood pressure
➤ Veins :
★ Carry deoxygenated blood
★ Thin wall
★ Have valve
★ Low blood pressure
➤ Blood capillaries :
★ Helps in exchange of materials between tissue and blood
→Nephron:
Structure:
Nephron contains glomerulus, Bowman’s capsule, and a long renal tubule.
Functions:
★ Waste materials in the blood are filtered and collected by Bowman’s capsule.
★ Glucose, amino acids, salts and water, re-absorbed and urine flows along the tube.
→Xylem:
★ transport of materials takes place in Xylem tracheids and vessels.
★ Unidirectional movement
★ Transpiration creates suction pressure and creates a column of water.
→ Phloem:
★ Transport food through Sieve tube and companion cells.
★ Bidirectional movement
★ it occur by Osmotic pressure.
Transpiration: process of removing excess of water from plant body.
Translocation: process of transport of food from leaves to other parts of plant.
→ Excretion in plants
★ Excess of water removed by transpiration
★ Remove oxygen and carbon dioxide gases through stomata
★ Resins and gums get store in old xylem
HOW DO ORGANISMS REPRODUCE
→ Reproduction:
★ living organism produce new individuals
★ DNA molecules is responsible for the transfer of characters from the parents to the off springs.
→ Types of Reproduction
★ Asexual reproduction :- new individual are produced from a single parent.
★ Sexual reproduction : - new individual are produced from a two parent.
→ Types of Asexual reproduction:
→ Binary fission:
Single cell divided into two cells
Ex: Amoeba, Leishmania
→ Multiple fission:
Single cell divided into many cells
Ex: Plasmodium
→ Fragmentation:
organism breaks up into smaller pieces on maturation each piece develops into new individuals.
Ex: Spirogyra
→Regeneration:
Broken part develop into new organism.
Ex: Planaria, Star fish, hydra
→ Budding:
bud like projection is formed on th body then it develops into a new individual.
Ex: Hydra
→ Spore Formation:
sporangia produce tiny cells called spores. When the spores come in contact with a surface, it develops into new individuals.
Ex: Rhizopus, mucor, penicillium
→ Advantages of vegetative propagation:
★ Early flowering and fruit formation.
★ To grow many plants like sugarcane, roses, or grapes.
★ Genetically similar plants produce.
→ Sexual Reproduction in Plants
→ Pollination
Transfer of pollen grains from anther to stigma
→ Self pollination:
Transfer of pollen grains from anther to stigma of same flower.
→ Cross pollination:
Transfer of pollen grains from anther to stigma of different flower.
→ Changes in flower after fertilization:
★ Zygote develop into Embryo
★ Ovule develop into Seed
★ Ovary develop into Fruit
★ Sepals and petals fall off
→ Male reproductive parts functions
★ Testis: Produce sperm and Testosterone hormone
★ Vas deferens: Transfer of sperm
★ Prostate and Seminal vesicles: Secrets fluid which helps sperm movement and provide nutrition.
→ Female reproductive parts functions
★ Ovary: Produce egg and estrogen hormone
★ Fallopian tube: transfer egg
★ Uterus: embryo development
→Placenta
★ Transfer oxygen and food from mother to embryo
★ Transfer waste form embryo to mother.
→ Development of an egg into a foetus in human female reproductive system.
★ The zygote divides and becomes an embryo.
★ The embryo is implanted in the lining of the uterus.
★ The embryo continues to grow and develop organs to become foetus.
→ Menstruation cycle
★ ovary produces one egg every month
★ uterus wall becomes thick and spongy.
★ If the egg is not fertilized, it breaks and comes out through the vagina as blood and mucous.
→ Contraceptive methods
★ Barrier method: Condoms, Diaphragm
★ Physical method: Copper T
★ Chemical method: Oral pills, Vaginal Pills
★ Surgical method: Tubectomy(female), Vasectomy(Male)
→ Sexual transmitted disease:
★ Virus: AIDS and Warts
★ Bacteria : Gonorrhoea and Syphilis
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CONTROL AND COORDINATION
→Reflex action:
★ Sudden response to stimulus.
★ Centre of reflex action is spinal cord
→Reflex arc:
★ Path of reflex action
★ Stimulus →Receptor →Spinal card→ Motor neuron→ effector
→ Neuron:
Structural and functional unit of nervous system.
Path of the movement of nerve impulses:
Dendrites → Cell body → Axon → Nerve ending
→ Synapse:
Gap between two neurons
Function: transmit chemical signal
→ Receptors
★ Photoreceptors in the eyes to detect light.
★ Phonoreceptors in the ears to detect sound.
★ Olfactory receptors in the nose to detect smell.
★ Gustatory receptors in the tongue to detect taste.
★ Tangoreceptors in the skin to detect touch.
→Brain parts function
★ Cerebrum: controls touch, smell, hearing, taste
★ Medulla: controls heart beat, blood pressure, coughing, swallowing, vomiting
★ Cerebellum: controls Body movement, balancing
→Plant Hormones
Plant hormones are chemical substance which control and coordinate the plant bady.
★Auxins: Cell elongation
★ Gibberillins: Growth of stem
★ Cytokinin: Cell division
★ Abscisic acid: Inhibits growth
★ Ethylene: Flowering and ripening of fruits
→ Auxins promote the growth of tendrils of climbing plants around a support
★ When tendrils come in contact with any support, auxins diffuse to the part of tendril which is away from the support.
★ Due to this, tendril grow faster than the part of tendril near to the support and causes the tendril to circle around the support.
→Tropic movement:
★ Phototropism: Plant growth response to light.
Ex: Growth of Shoot towards light
★ Geotropism: Plant growth response to gravity.
➤ Positive geotropism
Ex: Growth of root
➤ Negative geotropism
Ex: Growth of shoot
★ Hydrotropism: Plant growth response to water.
Ex: Growth of root towards water
★ Chemotropism: Plant growth response to chemical.
Ex: growth of pollen tube towards ovule
→ Non - Tropic movement in touch me not plant
★ Information of touch is conveyed from cell to cell through electrical chemical means.
★ As a result, plant cells change shape by changing amount of water in them. This causes the movement in plant.
→ Endocrine glands in Human being:
★ Pituitary gland - Growth hormone - controls body growth
★ Thyroid gland - Thyroxin - regulates carbohydrate, protein and fat metabolism
★Pancreas - Insulin - regulates blood sugar level
★ Adrenal gland - Adrenaline - Controls blood pressure and heart beat
★Testis - Testosterone - controls sperm production
★ Ovary - Estrogen - Controls egg production
OUR ENVIRONMENT
→ Food Chain:
Flow of food energy from one organism to the next
Ex:
★ Grass → Deer → Lion
★ Grass → Grasshopper → Frog → Snake → Eagle
★ Algae → Small insects → Large insects → Small fish → Large fish → Human.
→ Food web
Group of several interconnected food chains.
→ Trophic level
Steps of food chain where energy is transfer.
→ 10% law
Energy transfer decrease at every trophic level by 10%.
→ Ozone layer
ozone is a O3 molecules.
Formation:
O2 → O + OFunction:
★ Protect the earth from UV radiation.
★ UV radiation cause skin cancer.
CFC‘s are responsible for the decrease in the amount of ozone layer
→ Biological magnification:
increase of the harmful chemicals at higher trophic levels..
→ Biodegradable substance:
★ Degradable by microbes
★ Less harmful
★ Cause less pollution
★ Ex: peel of fruits and vegetables
If all the wastes we generate are biodegradable, then releases bad smell and causes air pollution. breeding ground for insects, pests and spread the diseases.
→Non- biodegradable substance
★ Cannot be degraded by microbes
★ More harmful
★ Cause more pollution
★ Ex: glass, plastic
Decomposers are microorganisms which decompose dead plants and animals.HEREDITY
The transfer of characters from the parents to their off springs is called heredity.
→ Monohybrid cross
Cross between one pair of character.
Ex: tall pea plant crossed with a short pea plant.
EX: Round seeded plant crossed with Wrinkled seeded plant
→ Dihybrid cross
Cross between two pairs of characters
Ex: Round green colour ( RRyy ) seeds producing pea plant is crossed with wrinkled yellow colour seeds ( rrYY ) producing pea plant.
The ratio of varieties of plants is = 9 : 3 : 3 : 1
Ex: tall pea plant bearing round seeds ( TTRR ) is crossed with dwarf pea plant bearing wrinkled seeds ( ttrr ).
→ Sex determination in human:
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