Cell Structure & Function

Cell Structure and Function

• The cell is the smallest basic structural unit of an organism
• Protoplasm is considered the physical basis of life

Unicellular Organisms

• Amoeba is a unicellular organism
• Mycoplasma is the smallest unicellular organism
• Ant is NOT a unicellular organism

Nucleus and Cell Components

• Cytoplasm is found in the nucleus
• The cell wall is absent in animal cells
• The cell wall allows certain substances to move in and out of the cell

Chloroplasts and Their Role

• Chloroplasts are found in plant cells, not animal cells
• Chloroplasts are responsible for the green color in plant cells
• Digestion is a function performed by the single cell of Amoeba

Staining Techniques

• Safranine stains the nucleus
• Cotton Blue stains fungus

Cell Structures and Their Functions

• Lysosomes are not typically found in plant cells
• Plastids are not found in animal cells
• Cell membranes have a semi-permeable tendency
• The nerve cell is the largest cell found in the body

Cell Discovery

• Cells were discovered in 1660
• The nerve cell is the largest cell in the human body
• The nucleus is where chromosomes are present in a cell

Cell Biology Basics

• Robert Hooke named the chambers he observed "cells"
• Bacteria lack a clear nucleus
• Fungus is a multicellular organism
• A living body’s structural and functional unit is the cell

Cellular Processes and Structures

• Protein synthesis occurs in the ribosome
• Mitochondria are the power house of the cell
• The outer covering of a plant cell is called the cell wall

Stomata and Leaf Structure

• Stomata are usually found in the lower layer of leaves
• Lysosomes are referred to as suicidal bags

Plant Cell Components

• Chloroplasts are the kitchen of the plant cell
• Vacuoles are empty structures within a cell
• Cellular respiration takes place in the mitochondria
• Cytoplasm is the jelly-like substance within cells

Genetics and Heredity

• Genes are carriers of genetic properties
• The cytoplasm contains organelles

Metals and Non-Metals: Key Differences

• Iodine is a non-metal that shines
• Sodium is stored in kerosene because it reacts readily with oxygen

Metals: Properties and Uses

• Sodium is a soft metal that can be cut with a knife
• Aluminum is used in packing food items due to its high malleability
• Metals are conductors of heat
• Non-metals are insulators of heat and electricity
• Metals typically have high melting and boiling points
• Metals commonly appear brown
• Brittleness is NOT a property of metals

Chemical Properties and Reactions

• White phosphorus reacts with air at room temperature
• Graphite is a non-metal that conducts electricity

Metallic and Non-Metallic Oxides

• Metallic oxides are often alkaline
• Non-metallic oxides are often acidic

Metals vs Non-Metals

• Sodium is among the most reactive metals
• Mercury is a metal found in liquid state
• Bromine is a non-metal that exists in liquid state at room temperature

Hardness and Ductility

• Diamond is a very hard non-metal
• Wood is a non-metal found in solid state
• Hydrogen is not a metal

Reactivity and Conduction

• Sulphur is not a metal
• Phosphorus is the most active non-metal
• Silver is a good conductor of electricity

Applications and Elements

• Magnesium finds use in fireworks
• Chlorine is used to purify water
• Graphite is used to make pencil lead
• Chlorine is used to prepare bleaching powder

Material Properties

• Metals that can be beaten into sheets have malleability
• Gold is the most ductile metal

Metal Characteristics

• Metals are ductile, allowing them to be stretched into wires
• Zinc can be beaten into thin sheets
• Mercury is a metal in liquid state at room temperature
• Sodium reacts quickly with cold water
• School bells are typically made of copper

Microorganisms: Ubiquitous Presence

• Microorganisms are found in water, air, and soil

Penicillin and Antibiotics

• Penicillin was the first antibiotic discovered
• Streptomycin is an antibiotic

Yeast and Alcohol Production

• Yeast is used in alcohol production

Antibiotics

• Streptomycin is an antibiotic
• Fermentation converts sugar into alcohol

Disease Transmission

• House flies are key in transmitting communicable diseases
• Mosquitoes are vectors of dengue parasites

Penicillin and Discoveries

• Alexander Fleming discovered penicillin
• Penicillin inhibits bacterial growth, thus preventing several diseases

Milk and Microorganisms

• Lactobacillus is the microorganism that converts milk into curd

Diseases and Pathogens

• Polio is caused by a virus
• Tuberculosis is caused by a bacteria
• Chlamydomonas is a unicellular algae

Malaria and Vectors

• Mosquitos cause malaria
• Female Anopheles mosquitos are the vector of malaria
• Malaria is caused by protozoa

Bacterial Diseases

• Tuberculosis is a bacterial disease
• The leaf extract of Cinchona treats Malaria and Dengue

Bacteria and Infections

• Cholera is caused by bacteria
• Typhoid is a common disease caused by bacteria
• Anthrax is caused by bacteria

Microorganisms

• Rhizobium is an example of a nitrifying microorganism
• A microscope helps to view microorganisms
• Bread puffs up due to the growth of yeast cells

Plant Diseases

• Wheat rust is caused by fungi
• Citrus Canker is caused by bacteria
• Ladyfinger yellow is caused by a virus
• Yeast is used in the wine industry

Disease

• Communicable diseases spread through air, water contact etc.
• Antibiotics destroy microorganisms and stopping their growth

Bread Making

• Carbon dioxide is produced while making bread

Milk Preservation

• Pasteurization preserves milk in packets

The Nitrogen Cycle

• The process of transporting nitrogen from the atmosphere is nitrogen fixation
• Yeast generates carbon dioxide during respiration

Electrical Effects

• Producing electric current results in heating, magnetic, and chemical effects

Electroplating

• Electroplating increases shine
• Electric current causes electroplating

Conductors and Insulators

• Distilled water is a non-conductor of electricity
• Brass is a good electric conductor
• Lemon juice is a good conductor of electricity
• Mercury is a non-conductor of electric current

Battery Components

• An electric cell has two terminals

Electrical Safety

• Electricians wear rubber gloves to prevent electric shock
• Conductors allow electricity to be conducted

Material Properties

• An electric current's heating effect is used in electric bulbs

Electroplating Properties

• To prevent rusting, iron bridges are electroplated with zinc (galvanization)

Conduction of electricity

• Rubber is not conductor of electricity

Electric Circuit and Components

• LED glows when current flows
• Color change indicates electrical current
• Electric current results chemical effects

Animal Reproduction: Fertilization

• Internal fertilization occurs inside the female body
• Hydra reproduces asexually through budding
• Fusion of male and female gametes is fertilization
• Fertilization occurs in the oviduct
• Zygotes contain one nucleus

Metamorphosis

• Metamorphosis occurs when tadpoles develops into adults
• Amoeba reproduces by binary fission

Gametes

• Gametes transfer characters from generation to generation

Reproduction and Species

• Reproduction is what makes the same spieces
• Zygotes form when male and female gametes join
• Animals that give direct birth are known as viviparous animals

Fertilization Placement

• Fertilization that takes place inside the body is called: Internal
• External fertilization takes place outside of the body

Animal Classification

• Frog undergoes external fertilization
• Internal fertilization happens in humans
• A zygote is formed when male and female gametes join

Asexual vs Sexual Reproduction

• In asexual production the original form is maintained

Pressure in Liquids

• Pressure in liquids increases with depth

Force

• Force is responsible for change in direction

Fundamental Physics Concepts

• Force applied by charged body is electrical
• Constant increased speed comes from gravitational force
• A force used to collect iron pins on the ground is magnetic

Contact and Non-Contact Forces

• Force on another object by direct touch is contact
• The attractive pull of the earth to everything is gravity
• When something is falling the gravitational force is on it

Combustion

• Essential components of combustion are a combustible substance, attaining ignition temperature, and presence of air

Fuel Types and Properties

• Hydrogen is most caloric fuel
• Dung cakes have the caloric value
• Kerosene is a combustible substance
• Oxygen assists combustion

Cooking and Fuels

• LPG is the best cooking fuel

Extinguishing Firess

• Extinguishers are not used if caught caught fire
• CO2 controls gases

Inlammable Gases

• Petrol is inflammable substance

Combustion Types

• Controlled/limited gas is used for combustion

Combustible Properties

• Wood indicates slow combustions.
• White phosphorus is used for spontaneous combustion

Properties of Combustion

• Excessive CO2 leads to global warming
• The internal part of flame is least hot

Gases

• CO is toxic

Measuring Heat

• Ignition temperature is the temp needs to start a fire

Adolescent Changes

• Changes don't occur during menopause
• In women mestruation is norm at 28 days
• Best fodd for adolescent are vegetables and fruits

Chromosomes

• A man has the XY chromosome

Types of Forces