Biology: Life Processes - Class 10th

Life Processes - Biology - Class 10th topics

• Nutrition, Respiration, Transportation, and Excretion are essential for life.
• Life processes are basic functions performed by living organisms to maintain life on earth.

Nutrition

• Nutrition involves obtaining and utilizing food.
• Nutrition supplies energy, as well as growth and development and for repair of damaged tissue.

Types of Nutrition

• Autotrophic Nutrition: Organisms prepare their own food.
  • Photosynthetic Autotrophic Nutrition includes green plants using chlorophyll and Blue-green algae.
    • Process involves photosynthesis, creating food in the form of glucose.
  • Chemosynthetic Autotrophic Nutrition: Purple - Sulfur Bacteria uses NH4, NO2, NO3 and chemical energy to produce food.
• Heterotrophic Nutrition: Organisms rely on others for food.
  • Holozoic Nutrition: Organisms ingest solid organic matter.
    • Organisms classified as Herbivores, Carnivores and Omnivores.
  • Saprotrophic Nutrition: Organisms feed on dead and decaying matter, such as Yeast, Bread mould, and Mushroom.
  • Parasite Nutrition: Organisms obtain nutrients from living organisms through external or internal parasites.
  • "Cuscuta" lacks chlorophyll, making it a parasitic plant.

Autotrophic Nutrition in Plants

• Plants need carbon dioxide (air), water (soil), light (sunlight), and chlorophyll (chloroplast) for autotrophic nutrition.
• Photosynthesis Reaction: 6CO2 + 12H2O + light energy -> C6H12O6 + 6H2O + 6O2.
• Chlorophyll aids in photosynthesis.
• Plants store glucose as Starch, while humans store it as Glycogen.

Photosynthesis

• Absorption of light energy by chlorophyll.
• Conversion of light energy to chemical energy, splitting water molecules into hydrogen and oxygen.
• Reduction of carbon dioxide into carbohydrates.

Stomatal Pore

• Stomata are tiny pores on the surface of leaves.
• Functions include transpiration and gas exchange for photosynthesis and respiration.
• Stomata opens on swelling when H2O enters guard cells.
• Stomata closes when shrinking caused by H2O moving out of guard cells.
• Night-time photosynthesis: Stomata open to absorb CO2.
• Day-time photosynthesis: Stomata close.

Food Processing

• Food travels through Ingestion, Digestion, Absorption, Assimilation, and Egestion.
• Ingestion is the process of taking in food.
• Digestion involves break down of food into smaller components for absorption within the bloodstream.
• Absorption is the process of absorbing digested food.
• Assimilation: Utilization of digested food for energy leading to growth and repair.
• Egestion refers to removing undigested food from the body.

Nutrition in humans

• Alimentary Canal: A long hollow alimentary canal containing (Oesophagus, and small and large intestines) to pass food through.
• Accessory Organs : Organs that aids but no food passes through them (liver, pancreas, and salivary glands)
• Food is ingested in the mouth.
• Food is crushed and chewed by teeth.
• Food is wetted to be smooth by creating saliva.
• Food is mixed by the muscular tongue.
• Amylase then converts complex sugar to simple sugars.

Esophagus Function

• Food moves downward through rhythmic muscle contractions and relaxation called peristaltic movements.

Stomach Function

• Stomach is a J-shaped organ being the widest part of alimentary canal
• Gastric juice comprises water, electrolytes, hydrochloric acid, pepsin, and mucus.
• Hydrochloric acid aids in conversion of pepsinogen to pepsin and kills bacteria
• Pepsin aids in protein digestion.
• Mucus provides a protective lining against hydrochloric acid & pepsin.
• Imbalance between hydrochloric acid and mucus causes hyperacidity and gastric issues.

Liver Function

• Secretes bile juice which is stored in the gallbladder
• Bile juice in the gallbladder
• Bile juice makes food alkaline and aids emulsification of fats.
• Emulsification is the breakdown of fats into smaller droplets via bile salts.

Pancreas Function

• Secretes pancreatic juice which contains enzymes.
• Trypsin aids in digestion of proteins.
• Lipase helps in emulsified fat break down.
• Pancreatic aids digestion of carbohydrates.

Small Intestine Function

• The small intestine measures 5-7 metres long.
• It is the site of final food digestion and secretes intestinal juice.
• The digestion walls secrete digestive enzymes to digest food.
• Peptidases split small peptides into amino acids.
• Maltase converts maltose into glucose.
• Sucrase converts sucrose into glucose and fructose.
• Lactase converts lactose into glucose and galactose.
• Lipases converts lipids into fatty acid and glycerol.

Absorption in Small Intestine

• Villi are finger-like projections that increase the surface area for absorption.
• Villi are richly supplied with blood vessels, which supply food to all body cells.
• Food is used for energy, building tissues, as well as old tissue repair.

Large Intestine (Colon)

• Large intestine absorbs water.

Anus

• Anus removes undigested and unabsorbed food.
• Herbivores have a longer intestine to digest cellulose, unlike carnivores.

Life process acronym

• MRS GREN: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, and Nutrition

Respiration

• Respiration occurs as a living organism obtains energy (ATP) by breaking down food in cells.
• Aerobic Respiration requires oxygen, occurring in the cytoplasm and mitochondria.
• Anaerobic Respiration happens without oxygen, occurring only in the cytoplasm.

Key equations.

• Note - ATP is the energy currency of the cell.
• C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP
• Aerobic respiration breaks down glucose into carbon dioxide and water.
• Anaerobic respiration converts glucose into ethanol (ethyl alcohol).

Exchange of gases in plants.

• Plants exchange gas via stomata in the leaves
• Plants exchange gas via lenticels.
• Photosynthesis consumes atmospheric CO2 but produces oxygen.
• Respiration consumes atmospheric oxygen but produces CO2.
• Gases are exchanged through stomata and lenticels, with intercellular spaces ensuring cell contact with air.
• CO2 and oxygen exchange through diffusion, depending on environmental conditions and plant requirements.

Respiration in Humans

• Inhalation brings air through the oral and nasal cavities, the pharynx, the larynx, the trachea, the bronchi and the lungs through alveoli
• Gas exchanges between oxygen rich and carbon dioxide rich at the alveoli level.

Gases in humans.

• Oxygen binds with hemoglobin in red blood cells for transport.
• Hemoglobin (containing iron) binds with O2 and helps in transporting O2
• CO2 is transported in dissolved form.
• Hemoglobin's affinity is higher for carbon monoxide than CO2.
• Volume of air remaining inside lungs after forceful exhalation is the residual volume (1100-1200 ml).
• Diaphragm muscles contract and flatten during inhalation and diaphragm arches upwards during exhalation.
• Air pressure surrounding lungs decreases during Inhalation.
• Air pressure surrounding lungs increases during exhalation.
• Inhalation brings air flow into the lungs.
• Exhalation is air forced out of the lungs

Alveoli

• Balloon-like structures one cell layer thick allow gas exchange.
• Balloon-like structures contain an extensive network of blood-vessels which helps in exchange of gases.

Gills

• Gills are respiratory organs for fishes to take oxygen from being dissolved in water.
• Aquatic organism breathing rate is faster because less oxygen can be disolved in water.
• Insects use spiracles and tracheae to take in oxygen.

Transportation

• Transportation enables synthesized or absorbed substances to be carried to all body parts.
• Blood transports food, CO2, O2, metabolic waste, and hormones.
• Transportation consist of blood, blood vessels and the heart (Blood - Fluid Connective tissue. and blood vessels)
• The blood is circulated into the body due it's fluids.

Blood

• Blood consists of blood plasma, serum and fibrinogen as well as blood corpuscles, RBC(Erythocytes), WBC(Leucocytes) and platelets(Thrombocytes)
  • Red Blood Cells: Circular, biconcave, disc-shaped, red due to Hemoglobin.
  • White Blood Cells: Large, nucleated, colourless.
  • Platelets: Cell fragments functioning in blood clotting
  • blood Delivers O2 and nutrients, hormones and pH and carries Buffers.
  • Transports wastes.
  • maintains body temperature as well fluid levels Prevents blood loss, and infections.

Types of blood vessels consist of

• arteries, veins and capillaries, where the body uses transportation between locations in the body.

Arteries

• Carries blood away from the heart as pure oxygenated blood passed except pulmonary artery
• Is a pressure is high.
• Rapid blood flow.
• Outer coat is thin with a middle coat being thick.
• Lumen is small, semi lunar valves are absent.

Veins

• Carries blood towards heart, with pressure being low (impure deoxygenated).
• Semi lunar valves are present to prevent back flow of Blood.
• The outer coat is thick and middle coat is thin with slow blood flow.
• Lumen is large.

Capillaries

• Link-artery to Vein
• The first part of the capillary with oxygenated blood that last part contains deoxygenated blood.
• Outer and middle coats are absent.
• Lumen is small with slow is slow blood flow.
• pressure is falling as it goes through.
• Valves in veins that prevent back-flow given low pressure.
• Arteries carry oxygenated blood away from the heart, veins carry deoxygenated blood to the heart, and capillaries facilitate exchange.

The Heart

• Largest Artery: Aorta
• Only artery that carries deoxygenated blood: Pulmonary Artery
• Largest Vein: Vena Cava
• Only Vein that carries oxygenated blood: Pulmonary Vein

The Heart Chambers and Circulation

• Pulmonary artery (Deoxygenated with the right and atrium.
• Lungs, the right ventricle.
• Body Organs with the left atrium
• Aorta in the left ventricle.
• Double Circulation
• Pulmonary vein (Oxygenated flows into the heart)
• Lung capillaries are Pulmonary to allow circulation
• Double Circulation enables blood to pass through the heart twice in each cycle.
• Pisces: 2-chambered heart, Single circulation, Cold blooded
• Amphibians: 3-chambered heart, Incomplete double circulation, Cold blooded.
• Reptiles: 4-chambered heart, Incomplete double circulation, Cold blooded.
• Aves: 4-chambered heart, Complete double circulation, Warm blooded.
• Mammals: 4-chambered heart, Complete double circulation, Warm blooded.
• Chambers in the heart is needed more respiration occurs when more energy is produced.

Double Circulation

• To prevent the mixing of oxygenated and deoxygenated blood supply needs to be increased to body organs
• Leads to an oxygen efficient supply to the body

Blood Pressure

• Blood pressure is the pressure exerted by blood in blood vessel walls.
  • Systolic Pressure measures pressure during ventricular contraction.
  • Diastolic Pressure measures pressure during ventricular relaxation.
  • Hypertension is when someone has high blood pressure because because arterioles begin to contract.

Lymphatic system

• Lymph is fluid that drains from extracellular space back into blood vessels.
• Lymph vessels carry fat from intestine to the bloodstream.
• Lymph nodes of the Lymph transports foreign material to fight pathogens.

Transportation in Plants

• Transporation of water, and the water and minerals is vital for the survival of all plant life.
• Xylem and Pholem is what allows the transportation of water and sustain the survival of the plant..

Xylem

• Water and minerals from roots to leaves for dead elements that transports unidirectional
• It has four types of cells: Tracheids, Vessels, Xylem parenchyma and Xylem fibres.

Pholem

• Pholem conducts food from leafs to all plant parts.
• Mainyl live elements of both transports.
• Has four types of cells: Phloem fibres, Sieve tubes, Companion cells and Phloem.
• Transports bidirectional and utilises ATP. Ascent of Sap is what allows the transport of water against graavity via the use of xylem tissue.

Transpiration (Evaporation.)

• Helps upward mobility, heat regulation and eliminates excess water.
• It has four types of cells: Tracheids, Vessels, Xylem parenchyma and Xylem fibres.
• Sieve Tubes (living) Phloem Fibre
• Companion Cells Pholoem contains Phloem Parenchyma:

Excretion

• Excretion expels metabolic waste and toxic substances.
• Metabolic waste:
  • • Carbon dioxide.
  • Excess mineral salts. • Excess water and Nitrogenous waste - nitrogen containing:
• Ammonia -Urea -Uric Acid

Excretory System

• Functions include removing waste, regulating blood, Producing hormones, managing blood and Maintenance if osmolairitiy in glucose.
• The human excretory system maintains blood pH, blood pressure, and blood glucose levels.
• It further regulates the ionic and gaseous composition.

Nephron

• Nephron main task is Glomerular Filtration: Nitrogenous wastes, glucose, water, amino acids, salts get filtered to initial filtrate which enters Bowman Capsule.
  • The, Nephron then uses selective reabsorption to filter anything left with high levels. -That final process, tubular Secretion will filter out urea and water to create urine which open into the collecting ducts.
• Hemodialysis (artificial kidney) filters blood for patients with kidney failure.
• Plants manage waste by diffusing gases through stomata, removing excess water via transpiration, and storing waste in cellular vacuoles or old xylem cells.