Biology 21st Century (OCR)

Chromosomes

Thread-like structures in the nucleus of cells made of DNA and protein that package genetic information.

DNA (Deoxyribonucleic Acid)

The molecule that carries genetic information, structured as a double helix.

Genes

Segments of DNA that contain instructions for building specific proteins that determine traits.

Heredity

The process of passing genetic information from parents to offspring.

Variation

Differences among offspring, caused by genetic inheritance and environmental factors.

Nucleus

Control center of the cell where genetic information is stored and protected.

Watson and Crick

Scientists known for creating the first accurate model of DNA's double helix structure.

Rosalind Franklin

Scientist whose X-ray diffraction images provided critical evidence for the structure of DNA.

Gametes

Specialized sex cells involved in reproduction (sperm and egg cells in animals).

Fertilization

Process where a sperm cell and an egg cell fuse to form a zygote.

Zygote

The first cell of a new organism formed from the fusion of gametes.

Embryo

Developmental stage following the zygote stage in sexual reproduction.

Petals

Colorful flower parts that attract pollinators in sexual reproduction of plants.

Pollination

Transfer of pollen from the male part of a flower to the female part for fertilization.

Asexual Reproduction

Reproduction that does not involve the fusion of gametes, producing genetically identical offspring.

Carbohydrates

Main source of energy for the body, found in foods like bread, rice, and fruits.

Lipids

Fats and oils that provide energy, insulate the body, and are needed for cell function.

Proteins

Essential compounds made of amino acids necessary for growth, repair, and tissue building.

Vitamins

Organic compounds needed in small amounts for various body functions.

Minerals

Inorganic elements needed in small amounts for various physiological processes.

Dietary Fibre

Indigestible part of plant foods important for digestive health.

Obesity

Condition resulting from excessive food intake and low physical activity leading to health risks.

Starvation

Condition resulting from insufficient food intake leading to energy and nutrient deficiency.

Scurvy

Disease caused by Vitamin C deficiency, characterized by bleeding gums and bruising.

Rickets

Disease caused by Vitamin D deficiency resulting in weak and soft bones.

Iron Deficiency Anemia

Condition caused by insufficient iron necessary for red blood cell production.

Heart

Muscular organ that pumps blood throughout the circulatory system.

Blood Vessels

Tubes in the circulatory system that carry blood; includes arteries, veins, and capillaries.

Arteries

Blood vessels that carry oxygenated blood away from the heart.

Veins

Blood vessels that carry deoxygenated blood back to the heart.

Capillaries

Tiny blood vessels where the exchange of substances between blood and body cells occurs.

Red Blood Cells

Cells that transport oxygen to body tissues.

White Blood Cells

Cells that are part of the immune system, helping to fight infections.

Platelets

Cell fragments that aid in blood clotting.

Plasma

Liquid component of blood that carries nutrients, hormones, and waste products.

Gut Bacteria

Beneficial bacteria in the digestive system that help with digestion and vitamin production.

Aerobic Respiration

Type of respiration that requires oxygen to produce energy from glucose.

Anaerobic Respiration

Type of respiration that occurs without oxygen, yielding less energy and producing lactic acid.

Fermentation

Anaerobic process in microorganisms that produces alcohol and carbon dioxide.

Digestive System

Organ system responsible for breaking down food into absorbable nutrients.

Mouth

Entry point for food; involved in mechanical and chemical digestion.

Esophagus

Tube that transports food from the mouth to the stomach.

Stomach

Organ where food is mixed with acid and enzymes for digestion.

Small Intestine

Main site of chemical digestion and nutrient absorption.

Large Intestine

Absorbs water from undigested food and forms feces.

Salivary Glands

Glands that produce saliva to aid in digestion.

Pancreas

Organ that produces digestive enzymes and regulates blood sugar.

Liver

Organ that produces bile for fat digestion.

Classification

The scientific process of grouping and naming organisms based on shared characteristics.

Fossils

Preserved remains or traces of organisms from the past.

Evolution

Process by which species change over time due to genetic variation and natural selection.

Habitat

Natural environment where an organism lives and thrives.

Adaptation

A trait that enhances survival and reproduction in a specific environment.

Competition

Struggle between organisms for resources such as food, water, and space.

Biodiversity

The variety of life in the world or in a particular habitat.

Extinction

The permanent loss of a species from the planet.

Pollution

Contamination of the environment that can harm organisms and ecosystems.

Conservation

Efforts to protect and preserve biodiversity and natural resources.

Natural Selection

The process where organisms better adapted to their environment tend to survive and produce more offspring.

Nutrient Absorption

The process by which nutrients from digested food are taken up into the blood.

Villi

Small, finger-like projections in the small intestine that increase surface area for absorption.

Osmosis

Movement of water through a semipermeable membrane from an area of low solute concentration to high solute concentration.

Diffusion

Movement of particles from an area of high concentration to an area of low concentration.

Gas Exchange

The process of taking in oxygen and expelling carbon dioxide.

Alveoli

Tiny air sacs in the lungs where gas exchange occurs.

Inhalation

Breathing in, increasing the volume in the lungs and decreasing pressure.

Exhalation

Breathing out, decreasing the volume in the lungs and increasing pressure.

Scientific Enquiry

An investigation process used by scientists to explore questions and gather evidence.

Hypothesis

An educated guess made prior to conducting a scientific experiment.

Data Analysis

The process of examining, cleaning, transforming, and modeling data to discover useful information.

Conclusion

A summary of findings that answers the original scientific question based on evidence.

Ecosystem

A community of living organisms interacting with one another and their non-living environment.

Trophic Level

Each level in a food chain or food web representing a step in energy transfer.

Autotrophs

Organisms that produce their own food using sunlight or chemical energy.

Heterotrophs

Organisms that obtain energy by consuming other living things.

Predators

Animals that hunt and consume other animals for food.

Prey

Animals that are hunted and consumed by predators.

Pollination

The transfer of pollen from the male to female parts of flowers for fertilization.

Symbiosis

A close and long-term interaction between two different species.

Mutualism

A type of symbiosis where both species benefit from the interaction.

Commensalism

A type of symbiosis where one species benefits and the other is neither helped nor harmed.

Parasitism

A type of symbiosis where one species benefits at the expense of the other.

Genetic Code

Sequence of nucleotides in DNA that determines the genetic instructions.

Cellular Respiration

Process by which cells convert glucose and oxygen into energy.

Element

A pure substance that cannot be broken down into simpler substances.

Compound

A substance formed when two or more elements bond together.

Chemical Reaction

A process that involves rearrangement of the molecular or ionic structure of a substance.

Organic Matter

Material that comes from living organisms.

Inorganic Matter

Substances that do not contain carbon-hydrogen bonds.