Photosynthesis and Leaf Structure

Photosynthesis

• Plants produce their own food through photosynthesis.
• Photosynthesis involves the reaction between carbon dioxide from the air and water absorbed by the roots.
• This reaction produces glucose (food for plants and other organisms) and oxygen.
• The chemical equation for photosynthesis is 6CO2 + 6H2O -> C6H12O6 + 6O2.
• Carbon dioxide enters the leaves through stomata.
• Water is absorbed by root hair cells.
• Chlorophyll, a green pigment in leaves, traps light energy (sunlight) for photosynthesis.

Leaf Structure

• Leaves are considered organs because they contain different layers.
• The cuticle is the waxy layer on top that prevents water loss.
• The upper epidermis is a transparent layer that allows sunlight to pass through.
• Palisade cells beneath the upper epidermis contain many chloroplasts for photosynthesis.
• Chloroplasts contain chlorophyll, which traps light energy.
• Stomata are tiny holes in the lower epidermis for gas exchange, allowing carbon dioxide to enter and oxygen to be released.
• Mesophyll consists of palisade and spongy layers, the latter facilitating gas diffusion.

Roots

• Roots anchor plants in the soil and absorb nutrients and water.
• Root hair cells are specialized to absorb water, having a large surface area.
• Water is transported from the root hair cells up to the leaves for photosynthesis.

Transport Systems in Plants

• Plants use vascular bundles (xylem and phloem) for transport, similar to blood vessels in humans.
• Xylem in the root has an "X" structure.
• Xylem transports water and mineral ions from the roots to the leaves.
• Phloem transports nutrients (sugars, amino acids) from the leaves to the rest of the plant.

Sexual Reproduction in Flowering Plants

• Flowering plants undergo sexual reproduction involving pollination and fertilization.
• The female part of the flower (pistil) consists of the stigma, style, ovary, and ovule.
• The male part of the flower (stamen) consists of the anther (produces pollen) and filament.
• Pollination occurs when pollen grains from the anther land on the stigma.
• A tube grows out of the pollen grain, creating a path for the male gamete to reach the ovule.
• The male gamete fuses with the female gamete inside the ovule, resulting in fertilization.
• After fertilization, the ovary becomes the fruit, and the ovule becomes the seed.
• Seeds are dispersed and, under the right conditions, grow into new plants.

Circulatory System

• The circulatory system is made up of the heart, blood, and blood vessels.

Heart Structure

• Humans have a four-chambered heart: two atria and two ventricles.
• The right atrium and ventricle are on the left side of diagrams, and vice versa.
• The atria are located on the top part of the heart.
• Blood flows from the atria down to the ventricles.
• The aorta is the main artery that carries oxygenated blood from the heart to the body.
• The pulmonary artery carries deoxygenated blood from the heart to the lungs for gas exchange.
• The vena cava is the main vein that carries deoxygenated blood from the body to the right atrium.
• Pulmonary veins carry oxygenated blood from the lungs to the left atrium.
• The diagram's left side (left atrium, left ventricle) carries blood high in oxygen.
• The diagram's right side (right atrium, right ventricle) carries blood low in oxygen.

Oxygenated vs. Deoxygenated Blood Flow

• The left side of the heart (diagram) always carries oxygenated blood.
• The right side of the heart (right atrium and right ventricle) always carries deoxygenated blood.
• "LORD" (Left is Oxygenated, Right is Deoxygenated) is a mnemonic to remember the sides of the heart.

Path of Deoxygenated Blood

• Deoxygenated blood from the body enters the right atrium through the vena cava.
• Blood flows from the right atrium to the right ventricle.
• The pulmonary artery carries blood from the right ventricle to the lungs for gas exchange.

Path of Oxygenated Blood

• Oxygenated blood from the lungs enters the left atrium through the pulmonary vein.
• Blood passes through a valve from the left atrium to the left ventricle.
• The aorta carries blood from the left ventricle to distribute to the whole body.

Double Circulation

• The human circulatory system has double circulation.
• First circulation route: heart to lungs, back to heart (blood oxygenation).
• Second circulation route: heart to body, back to heart (nutrient/waste transport).
• Blood gets oxygen during circulation through the lungs.
• Carbon dioxide is released and oxygen is absorbed in the lungs.

Pulmonary Vein Function

• Pulmonary vein carries oxygen-rich blood from the lungs back to the heart.
• Veins carry blood into the heart ("veIN").
• Vena cava is the main vein.

Artery Function

• Arteries carry blood away from the heart (opposite of veins).
• Aorta is the main artery.
• Pulmonary artery carries blood from the heart to the lungs.

Circulation from Heart to Body

• The heart pumps oxygen-rich blood to the body through the aorta.
• Blood picks up nutrients from digestive system during this circulation.
• Blood picks up carbon dioxide and cell waste.
• Vena cava carries blood back to the heart.

Three Types of Blood Vessels

• Humans have veins, arteries, and capillaries.
• The aorta distributes blood throughout the body via arteries, then capillaries.

Veins

• Veins carry blood to the heart; generally deoxygenated.
• Pulmonary vein is an exception; carries oxygenated blood.
• Veins have thin walls and larger passageways for blood flow.
• Veins contain blood under low pressure.
• Valves in veins prevent backflow due to gravity, especially from lower body.

Arteries

• Arteries carry blood away from the heart; generally oxygenated.
• Pulmonary artery is an exception; carries deoxygenated blood.
• Arteries have thick, muscular walls and small passageways.
• Arteries contain blood under high pressure due to heart's pumping action.

Capillaries

• Capillaries facilitate exchange between blood and tissues.
• Substances exchanged: oxygen, carbon dioxide, water, food, and waste.
• Capillaries are only one cell thick.
• Capillaries have very low blood pressure.

Blood Components

• Blood contains different kinds of blood cells floating in plasma (liquid).
• Red blood cells transport oxygen.
• Red blood cells shape maximizes surface area for oxygen absorption.
• White blood cells destroy invading microorganisms.
• White blood cells have a large nucleus.
• Platelets help blood to clot.
• Plasma transports dissolved substances such as sugar.

Balanced Diet

• A balanced diet contains the correct amount of seven nutrients: carbohydrates, fats, proteins, vitamins, minerals, dietary fiber, and water.

Digestion

• In digestion, food is broken down into tiny particles for absorption into the blood.
• Provides energy + enables growth, repair and overall health

Digestion Process

• Digestion begins in mouth with teeth and tongue breaking food into smaller pieces (mechanical digestion)
• Salivary glands secrete amylase which breaks down starch to maltose (chemical digestion)

Esophagus

• Peristalsis and gravity move food down esophagus to stomach

Stomach

• Stomach produces HCl to help kill germs and prepares gastric area for enzyme action

Enzymes in Stomach

• Pepsin: breaks down proteins
• Rennin: breaks down milk proteins (children)
• Lipase: breaks down emulsified fats

Liver

• Liver produces bile

Gallbladder

• Gallbladder: Stores bile produced by the liver and releases it into small intestine to emulsify fats

Pancreas

• Pancreas secretes enzymes released into small intestine
• Pancreatic amylase: breaks down starch
• Pancreatic lipase: breaks down fats
• Pancreatic proteases: break down proteins

Small intestine

• Converts lactose to simple sugars.
• Converts maltose to glucose.
• Converts sucrose to simple sugars.
• Peptidases break down proteins to amino acids
• Produces enzyme; prepares foods for absorption

Large Intestine

• Large intestine absorbs water and some nutrients.
• Large intestine collects food residue for excretion.

Enzymes as Biological Catalysts

• Chemical digestion involves many enzymes, which are proteins that function as biological catalysts.

Molecules

• Large food molecules (starch/proteins/fats) require enzymes to break them down.
• Starch (carbohydrates): amylase and maltase ->glucose
• Proteins: proteases ->amino acids
• Fats: lipases -> glycerol and fatty acids

Inhalation

• Inhalation is the process of taking of air rich in oxygen.

Exhalation

• Exhalation is giving out the air rich in carbon dioxide.

Breathing

• Breathing is the process of inhalation and exhalation which takes place in lungs

Lungs

• During inhalation, chest expands, ribs move forward, diaphragm contracts (flattens).
• During exhalation, chest contracts, diaphragm relaxes.

Respiration Equation

• Glucose + Oxygen -> Carbon Dioxide + Water + Energy (ATP)

Respiration

• Respiration is a chemical reaction which occurs in all living cells releasing energy from glucose

Respiratory System

• Trachea, bronchi, lungs, diaphragm and the muscles between the ribs are the organs of the respiratory system.

Parts of Respiratory System and Their Function: NOSE/MOUTH

• Entry points

Parts of Respiratory System and Their Function: TRACHEA

• Major Airway to the lungs

Parts of Respiratory System and Their Function: BRONCHI

• Direct air into left and right lungs.
• Bronchi is the plural for bronchus.

Parts of Respiratory System and Their Function: ALVEOLI

• Air moves to the alveoli where there is gas exchange
• Gas exchange occurs by diffusion.
• Surrounded by capillaries

Parts of Respiratory System and Their Function: INTERCOSTAL MUSCLES

• Contract and relax with diaphragm

Parts of Respiratory System and Their Function: DIAPHRAGM

• Dome-shaped muscle that contracts and relaxes with intercostal muscles during breathing

Function of Skeletal System

• Supports the body
• Motion
• Protects organs
• To make blood cells.
• Rib cage protects the heart and lungs.
• Important to give shape to the body.

Skull

• The Skull protects the brain

Backbone

• Protects backbone protects the spinal cord

Joints

• The bone at fix joints cannot move,
• The bone is at hinge joint or ball and socket joint can move
• Cartilage and synovial fluid reduce friction at removable joints

Joint Types

• Fixed joints: Bones cannot move (e.g., joints in the cranium).
• Movable joints: Bones can move (e.g., ball-and-socket joints in the shoulder, hinge joints in the knee).
• Cartilage and synovial fluid reduce friction in movable joints.

Muscle in skeletal System

• Muscles that attach to the skeletal system is called skeletal muscles muscles that can contract or relax

Tendons

• Muscles connect to the skeletal bone via tendons.

Muscles

• Muscles can pull but cannot push.

Antagonist Muscles

• To be able to move both directions, a pair of muscles needs to work together
• Ex. biceps and triceps contract at bending motion/lowering motion

Musclue Interaction: BENDING ELBOW

• Biceps contract to bend the elbow
• Triceps contract to straighten and lower the arm

Sexual Reproduction

• Sexual reproduction in humans require both male and female parents.
• Males produce male gametes (sperms); females produce female gametes (eggs).

Gametes and Chromosomes

• Eggs and Sperm are haploid cells containing 23 chromosomes
• Fertilized egg/zygote has 46 chromosomes (diploid)

Fertilization

• Egg and sperm have the same amount of chromosome to fuse.
• The egg is zygotes because sperm and eggs refuse a single nucleus.

Sperm Origin

• Sperm cells are produced in the testis

Sperm travel to:

• Sperm duct
• Urethra

Eggs Origin

• Egg cells are made in the ovaries then travel along the oviduct

Zygote

• Is when fertilized zoygote divides to create embryo

Implantation

• Embryo travels to uterus to attatch it self in the wall of uterus for development as a "foetus"

Menstration

• If egg is not, thick lining in the uterus breaks due to menstruation

Foetus Protected by these structures: : PRESENTa

• Protects substances that pass between the blood of the mother and the foetus.

Foetus Protected by these structures: UMBILICAL CORD

• Passes substances between blood center and foetus

Foetus Protected by these structures: AMNION

• A protective set filled with amniotic fluid

Complete Form Foetus:

• When physicist had have finished growing up to the 38-39 weeks after fertilizaiton

Mrs. Gren

• "Mrs. Gren" is an acronym to remember the characteristics of living things.

Movement

• Change in position by the action of muscles in animals
• Slow growth movements in plants

Respiration

• Process by which living cells release energy from organic molecules.

Sensitivity

• Ability to detect and respond to changes inside/outside environment

Growth

• Increase in size and mass

Reproduction

• Creation of new organisms that are the same species as parents.

Excretion

• Removal of waste from the organism's body.

Nutrition

• Supplies an organism nutrients to respire for growth.

###Microorganism

• Living organisms that are too small that they are not visible by the eye :
• bacteria, fungi, virsuses
• protozoa

Beneficial function organism : Bacteria

• Can be good and bacteria : ex, antibiotics

Harmful function organism : Fungi

• Are parasites that can be

Properties of Metals and Non-metals

• Metals typically exhibit a shiny appearance, while non-metals appear dull.
• At room temperature, metals are generally solid, with the exception of mercury, which is a liquid used in thermometers.
• Non-metals at room temperature are present in various states, with roughly half being solid and half being gases; bromine is a notable exception as it exists as a liquid.
• Metals have high density, making them heavy.
• Non-metals have low density, making them light.
• Metals are strong and malleable, meaning they can bend without breaking.
• Non-metals are generally weak and brittle, causing them to break or shatter when hammered.
• Metals are good conductors of heat.
• Non-metals are poor conductors of heat and serve as good insulators.
• Metals are good conductors of electricity.
• Non-metals are insulators, except for graphite.
• Only iron, cobalt, and nickel are magnetic materials among metals.
• Non-metals generally do not exhibit magnetic properties.
• Metals produce a ringing sound when struck, and are thus sonorous.
• Non-metals produce a dull sound upon impact.

Group 1 Elements (Alkali Metals)

• Group 1 elements are known as alkali metals, and include lithium, sodium, potassium, rubidium, cesium, and francium.
• Alkali metals have one electron in their outer shells, which results in high reactivity and similar properties.
• Compared to other metals, alkali metals have low densities and are relatively soft.
• Reactivity increases, atomic mass increases, and melting/boiling points decrease as you move down Group 1.
• Alkali metals react vigorously with water to produce hydrogen gas and metal hydroxide, leading to an alkaline solution.
• Sodium reacts with water to form sodium hydroxide and hydrogen gas (2Na + 2H2O → 2NaOH + H2).
• The reaction between sodium and water produces bubbles of hydrogen gas and causes the sodium metal to melt into a shiny ball that moves rapidly on the surface.
• Sodium hydroxide (NaOH) formed in this reaction creates a highly alkaline solution with a pH around 14.
• Group 1 metals react with oxygen to form metal oxides, like lithium reacting with oxygen to form lithium oxide.

Material Changes - Physical vs Chemical

• Material changes can be categorized as either physical or chemical.
• Physical changes are mostly reversible, do not form new substances, and retain the substance's chemical properties (e.g., dissolving sugar, evaporating water).
• Chemical changes are not reversible, result in the formation of one or more new substances, and the new substances have different properties from the original substance (e.g., burning a match, rusting of iron).

Acids and Alkalis

• Acidity is measured using the pH scale, where values below 7 are acidic, values above 7 are alkaline/basic, and a value of 7 is neutral.
• Examples of pH values and substances: battery acid (0), stomach acid (1), lemon juice (2), wine (3), bananas (4), coffee (5), milk (6), pure water (7), blood (8), egg white (9), household bleach (10), household ammonia (11), hair removal (12), oven cleaner (13), and drain cleaner (14).
• An acid is a substance with a pH lower than 7.
• An alkali is a soluble substance with a pH higher than 7.
• pH can be tested using a pH meter which gives a numerical pH value OR an indicator (litmus paper or universal indicator).
• Universal indicator shows different colors at different pH values. Very red indicates very acidic, getting lighter (orange, yellow) to green then blue, and purple indicates very alkaline.

Reactions Involving Acids

• Acid + Alkali yields a neutral solution to create salt and water.
• Hydrochloric acid (HCl) plus sodium hydroxide (NaOH) yields sodium chloride (NaCl) plus water (H2O).
• Metal + Acid yields salt and hydrogen.
• Calcium metal plus hydrochloric acid produces calcium chloride plus hydrogen.
• Metal Carbonate + Acid yields salt, carbon dioxide, and water.
• Copper carbonate plus sulfuric acid yields copper sulfate, carbon dioxide, and water.
• The copper sulfate will remain in solution, while the carbon dioxide gas produced can be channeled into lime water turning it milky or cloudy.

Detecting Chemical Reactions

• Bubbles form when the chemicals are mixed
• There is a temperature change.
• There is a color change.
• A solid or substance is formed.

Rusting

• Rusting is a type of corrosion specific to iron.
• Iron plus water plus oxygen yields hydrated iron (III) oxide (rust).
• Rusting can be prevented by eliminating either air or water. The presence of both lead to rusting.

Energy Changes in Chemical Reactions

• Endothermic reactions absorb energy and the temperature drops.
• Exothermic reactions release energy and the temperature increases.
• Examples of exothermic reactions include combustion, burning, and neutralization reactions.
• Examples of endothermic reactions include the reaction between ethanoic acid and sodium carbonate, thermal decomposition of calcium carbonate, and photosynthesis.
• Examples of exothermic reactions: heat from water and acid interaction, nuclear fission, campfire, rusting, freezing water.
• Examples of endothermic reactions: evaporating water, baking bread, frying egg, photosynthesis.
• In exothermic heat is released from a reaction.
• In endothermic reaction heat is absorbed by a reaction.

Reactivity Series of Metals

• The reactivity series lists metals in order of their reactivity, from most reactive to least reactive.
• Examples of the reactivity series include the following metals (most to least): potassium, sodium, lithium, calcium, magnesium, aluminum, zinc, iron, tin, lead, copper, mercury, silver, and gold.
• The more reactive a metal is: will react with water (and from the bottom of the list, they all react with acids / oxygen)
• Potassium reacts explosively if reacting with acids.
• Magnesium reacts vigorously (but not as explosively as potassium) with acids
• Zinc reacts slowly with acids
• Mnemonic to remember the order: "Please stop calling me a cute zebra. I like her call, not goat" [Potassium, Sodium, Calcium, Magnesium, Aluminum, Zinc, Iron, Lead, Copper, Silver, Gold].

Reactions of Metals With Other Substances

• Metal + Oxygen yields Metal Oxide
• Metal + Water yields Metal Hydroxide + Hydrogen Gas
• Metal + Acid yields Salt + Hydrogen Gas
• More reactive metal will displace a less reactive metal from a solution.
• A less reactive metal will not displace a more reactive metal from a solution.
• Magnesium will not be able to displace magnesium from its solution.

Rates of Reaction

• The rate of reaction measures how quickly a reactant is used up or a product is formed.
• Reaction prerequisites: reactant particles must collide, sufficient energy must be present to overcome energy barriers, and reactants must form new bonds.
• Factors affecting rate: temperature, concentration, surface area, presence of catalyst.

Factors that increase Reaction Rate

• Increase in temperature - increases the kinetic energy of particles. Particles move faster, collide more frequently.
• Increase in concentration - more particles cause collisions to occur more often.
• Increase in surface area - increases potential contact with other particles.
• Catalyst - lowers the activation energy required for the reaction.
  • Catalyst increases the rate of reaction by lowering the activation energy, making it easier for reactants to form products.

Measuring Rate of Reaction

• Measure loss in mass of reactants over time.
• Measure volume of gas produced over time.
• Measure time for solution to become opaque or colored.
• Graph shows change in the rate of reaction over time:
  • Low temperature/concentration, and larger pieces of metal have lower gradients, with the reaction less steep over time.
  • Higher temperature/concentration or catalysts will increase the slope / rate of reaction.
  • The sign for the reaction stopping is a horizontal line on the graph.

Forces and Motion

• A force is a push of pull that is able to change the shape of an object, or change the way it moves.
• Example: Batted ball changes direction when hit.
• Example: Spring stretches when forced applied to it.

Resultant Force

• Resultant Force is the net force
• If the resultant force is NOT zero, the forces are unbalanced.
• If the resultant force IS zero - then the forces are balanced.
• IF the forces are balanced - then the object will move at a constant speed.
• Friction force is a force that slows down moving objects.
• Friction can be either helpful OR unhelpful.
  • Helpful Friction: bicycle brakes help slow the bike.
  • Unhelpful Friction: wears down the tires on a car.

Weight and Mass

• Weight is the force of Earth's gravity on an object.
• Mass is the amount of matter in an object.
• Weight = mass * gravitational field strength
  • Weight = Newton
  • Mass = kilogram
  • Gravitational Field Strength = Newton/Kilogram
• Gravitational field strain on earth is 9.8 Newton / Kilogram, rounded to 10 Newton / Kilogram.
• The force of gravity on every planet OR object depends on its mass OR size.

Weight and Gravity

• Weight on Earth differs from weight on the Moon due to varying gravitational values.
• Moon's gravitational value is approximately 1.6 Newton per kilogram.
• Weight (W) is calculated using the formula: W = m * g, where 'm' is mass and 'g' is gravitational field strength.
• Mass remains constant regardless of location, while weight changes with gravitational field strength.
• An object with a mass of 72 kg will have varying weights on different planets due to differing gravitational field strengths.

Air Resistance (Drag)

• Air resistance is a frictional force exerted by air against a moving object.
• As a parachutist jumps, gravity pulls them down, causing acceleration.
• Downward speed increases, so does air resistance.
• Drag force acts against the downward force (gravity).
• Terminal velocity is reached when drag balances the weight due to gravity, resulting in no acceleration.
• Opening the parachute causes deceleration due to a significant increase in drag.
• A new, smaller terminal velocity is reached after the parachute opens, when drag and gravity balance again.

Density

• Density is the mass per unit volume of a substance.
• Formula: density = mass / volume.
• Unit for density: kilogram per cubic meter (kg/m³) or gram per cubic centimeter (g/cm³).
• Solids and liquids are generally more dense than gases because their particles are packed more closely together.
• An object will float on a liquid if it is less dense than the liquid.

Pressure

• Pressure is the measure of force acting on an area.
• Formula: pressure = force / area.
• Unit for pressure: Newton per square meter (N/m²) or Pascal (Pa).
• Smaller area creates greater pressure with the same force acting on it.
• A woman wearing shoes with pointed heels exerts greater pressure due to the small contact area compared to an elephant, despite the elephant's much larger weight.
• Increasing the area reduces the pressure.

Pressure in Liquids and Gases

• Liquids are incompressible, unlike gases that are compressible.
• Compressing a gas into a smaller volume increases its pressure.
• In smaller spaces, gas particles collide more frequently with the container walls, increasing pressure.
• Increasing the temperature of a gas increases its pressure.

Turning Effect (Moment of Force)

• A force can cause an object to turn clockwise or anti-clockwise about a pivot.
• The turning effect of a force is called the moment of the force.
• The principle of moments states that when an object is balanced, the clockwise moment equals the anti-clockwise moment.
• Formula: moment = force * perpendicular distance from the pivot (M = F * d).