Biology Chapter: DNA and Cell Division

DNA Structure and Components

• DNA is a double helix, resembling a twisted ladder.
• The "rungs" of the ladder are made of nitrogenous bases (adenine, thymine, guanine, cytosine).
• Adenine pairs with thymine, and guanine pairs with cytosine.
• The "sides" of the ladder are made of sugar-phosphate backbones.
• DNA carries genetic instructions for all living organisms.

Sex Chromosome Structure

• Sex chromosomes determine an organism's sex.
• Humans have 23 pairs of chromosomes.
• One pair is the sex chromosomes (XX for females, XY for males).
• The Y chromosome carries the gene for maleness.

Mitosis, Meiosis, Mutation, Non-Disjunction

• Mitosis is cell division resulting in two identical daughter cells.
• Meiosis is cell division resulting in four genetically different daughter cells (used in sexual reproduction).
• A mutation is a change in the DNA sequence.
• Non-disjunction is the failure of chromosomes to separate properly during cell division, potentially leading to genetic disorders.

Atomic Structure and Electron Movement

• Atoms have a nucleus containing protons and neutrons.
• Electrons orbit the nucleus in specific energy levels.
• Electrons can move between energy levels by absorbing or releasing energy.

Types of Bonding

• Ionic bonding: Atoms transfer electrons to form ions, which attract each other.
• Covalent bonding: Atoms share electrons to achieve stability.
• Metallic bonding: Electrons are shared among many atoms, allowing for properties like electrical conductivity.

Element Definition

• An element is a substance composed of only one type of atom.

Science Definition

• Science is a systematic approach to understanding the natural world.

Biology Definition

• Biology is the study of living organisms.

Hypothesis Definition

• A hypothesis is a testable explanation for a phenomenon.

Types of Chemistry

• Organic chemistry: Study of carbon-based compounds.
• Inorganic chemistry: Study of non-carbon-based compounds and their reactions.
• Physical chemistry: Study of the physical and thermodynamic aspects of chemical systems.
• Analytical chemistry: Study of the composition of matter.

Acidity and Basicity

• Acidity refers to the concentration of hydrogen ions (H+) in a solution.
• Basicity refers to the concentration of hydroxide ions (OH-) in a solution.

Eukaryotic and Prokaryotic Cells

• Eukaryotic cells contain a nucleus and other membrane-bound organelles.
• Prokaryotic cells lack a nucleus and other membrane-bound organelles.

ATP Function

• ATP (adenosine triphosphate) is the primary energy currency of cells.
• It releases energy when a phosphate bond is broken.

Filtration, Diffusion, Osmosis, Active Transport

• Filtration separates substances based on size.
• Diffusion is the movement of molecules from high to low concentration.
• Osmosis is the diffusion of water across a selectively permeable membrane.
• Active transport moves molecules against their concentration gradient, requiring energy.

Reactant, Solution, Precipitate, Product, Compound, Chemical Reaction

• Reactants are substances involved in a chemical reaction.
• A solution is a homogeneous mixture of two or more substances.
• A precipitate is a solid that forms from a solution.
• Products are substances formed in a chemical reaction.
• A compound is a substance formed by the chemical combination of two or more different elements.
• A chemical reaction is a process that transforms one or more substances into different ones.

Homogeneous and Heterogeneous Mixtures

• Homogenous mixtures have uniform composition; examples include saltwater and air.
• Heterogeneous mixtures have non-uniform composition, varying throughout the mixture; examples are sand and water, vegetable soup.

Evolution

• Evolution is the change in heritable characteristics of biological populations over successive generations.

Hydrogen Bonding in Water, Carbon Dioxide, Carbon Monoxide

• Hydrogen bonding in water: The polar nature of water molecules creates hydrogen bonds that give water its unique properties.
• Carbon Dioxide: A linear molecule, not involved in hydrogen bonding.
• Carbon Monoxide: A linear molecule, not involved in hydrogen bonding.

Mass, Weight, Density, Solid, Liquid, Gas, Matter, Mixture

• Mass: Measure of the amount of matter in an object.
• Weight: Measure of the force of gravity on an object.
• Density: Mass per unit volume.
• Solid: Definite shape and volume.
• Liquid: Definite volume, takes the shape of its container.
• Gas: No definite shape or volume, fills its container.
• Matter: Anything that has mass and occupies space.
• Mixture: Combination of two or more substances that are not chemically bonded.

Bacteria and Viruses

• Bacteria: Prokaryotic single-celled organisms.
• Viruses: Non-cellular entities that require a host cell to replicate.

Animal Cell Anatomy

• Animal cells have a nucleus, cytoplasm, and cell membrane.

Biological Structures (Smallest to Largest)

• Atom → Molecule → Organelle → Cell → Tissue → Organ → Organ System → Organism

Human Body Systems

• Skeletal: Provides support and protection.
• Muscular: Enables movement.
• Respiratory: Facilitates gas exchange.
• Cardiovascular: Transports nutrients and oxygen.
• Immune: Protects against diseases.
• Integumentary: Forms the outer covering of the body.
• Endocrine: Regulates hormone levels.
• Nervous: Controls bodily functions.
• Reproductive: Enables reproduction.
• Digestive: Breaks down food.

Cardiovascular System Anatomy and Blood Flow

• Heart (atria, ventricles), blood vessels (arteries, veins, capillaries).
• Blood flows from the heart to the body and returns to the heart.

Blood Components

• Blood consists of plasma (liquid component) and blood cells (red blood cells, white blood cells, platelets).

Blood Cell Types

• Red blood cells (erythrocytes) carry oxygen.
• White blood cells (leukocytes) fight infection.
• Platelets (thrombocytes) help in blood clotting.

Muscle Types

• Skeletal muscles (voluntary movement), cardiac muscle (heart), smooth muscle (involuntary movement).

Insulin Function

• Insulin regulates blood glucose levels.

Fertilization, Ovulation, Menstruation

• Fertilization: Fusion of sperm and egg.
• Ovulation: Release of egg from ovary.
• Menstruation: Shedding of uterine lining if fertilization does not occur.

Nose, Mouth, Hair, Nails Anatomy and Function

• Nose: Respiration, smell.
• Mouth: Ingestion of food, speech.
• Hair: Protection, insulation.
• Nails: Protection, gripping.

Plant Categories

• The major plant categories include flowering plants, conifers, ferns, mosses etc.

Water Uptake by Plants

• Plants absorb water through their roots via osmosis.

Air Exchange in a Leaf

• Air exchange in leaves occurs through stomata.

Plant Cell Structure and Function

• Plant cells have a cell wall, a nucleus, chloroplasts (for photosynthesis), and a large vacuole.

Cellulose Function

• Cellulose provides structural support to plant cells.

Plant Pollination

• Plants are pollinated by wind, water and animals (such as insects and birds).

Photosynthesis and Respiration

• Photosynthesis: Plants use sunlight to convert carbon dioxide and water into glucose and oxygen.
• Respiration: Plants and animals use glucose and oxygen to produce energy.

This quiz tests your knowledge on DNA structure, sex chromosomes, and the processes of mitosis and meiosis. Understand the fundamental components of genetic material and how cells divide. Perfect for biology students looking to reinforce their learning.