bio yr 10 exam

Cell

The basic functional unit of all living organisms.

Cell Theory

1. All living things are composed of cells. 2. Cells are the basic unit of structure and function of life. 3. New cells come from pre-existing cells.

Eukaryote Cell

A complex cell type; eu means 'true' and kary means 'nucleus', typically multicellular.

Plant Cell Features

Contains a nucleus, ribosome, chloroplast for photosynthesis, mitochondria for energy, and a cell wall for structure.

Animal Cell Features

Contains a nucleus, ribosome for protein synthesis, and a cell membrane.

Prokaryote

A simple cell type (e.g., bacteria) that is unicellular and lacks a true nucleus.

Cell Membrane

A barrier that controls the movement of substances in and out of the cell.

Diffusion

Movement of particles from areas of high concentration to areas of low concentration.

Surface Area

Total area of the external environment/membrane.

Volume

Total internal space within a cell.

Osmosis

Diffusion of water across a semi-permeable membrane from high water concentration to low water concentration.

Hypotonic Solution

A solution with a lower solute concentration than the cell, causing water to enter the cell and increase volume.

Isotonic Solution

A solution with equal solute concentration to the cell, resulting in no net water movement.

Hypertonic Solution

A solution with a higher solute concentration than the cell, causing water to leave the cell.

DNA

Deoxyribonucleic acid, stores genetic information and provides instructions for proteins.

Nucleotide

Basic building block of DNA, consisting of a phosphate group, deoxyribose sugar, and a nitrogenous base.

Gene

A sequence of DNA that codes for a protein.

Chromosome

Long condensed strands of DNA wrapped around proteins called histones.

Telomere

Protective base sequence at the end of chromosomes.

Centromere

Region that holds sister chromatids together.

Aneuploidy

Condition of having too few or too many chromosomes.

Somatic Cells

Body cells that have two sets of chromosomes (diploid).

Gametes

Sex cells that contain one set of chromosomes (haploid).

Cell Cycle

Series of events that lead to the division and duplication of a cell, producing two genetically identical daughter cells.

Interphase

Phase of the cell cycle where the cell prepares for division.

Synthesis Phase (S Phase)

Stage of interphase where chromosomes duplicate and become double-stranded.

Mitosis

Process of producing two identical daughter cells.

Prophase

First stage of mitosis where chromosomes are duplicated and the nuclear membrane breaks down.

Metaphase

Stage of mitosis where chromosomes align in the center of the cell.

Anaphase

Stage of mitosis where sister chromatids separate at the centromere.

Telophase

Final stage of mitosis where nuclear membranes reform around each set of chromosomes.

Cytokinesis

Process where the cytoplasm divides, resulting in two daughter cells.

Meiosis

Cell division that produces four gamete cells, each with half the number of chromosomes.

Crossing Over

Exchange of genetic material between homologous chromosomes during prophase 1 of meiosis.

Independent Assortment

Random arrangement of chromosomes during metaphase 1 of meiosis leading to genetic diversity.

Dominant Traits

Traits expressed with a capital letter. Can mask recessive traits.

Recessive Traits

Traits expressed with a lowercase letter, overshadowed by dominant traits.

Homozygous

Genotype consisting of two identical alleles.

Heterozygous

Genotype with different alleles.

Phenotype

Physical expression or characteristics of a trait.

Punnett Square

Tool used to predict the genetic outcome of a cross between organisms.

Sex Linked Traits

Traits carried on sex chromosomes.

Natural Selection

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

Gene Pool

Total collection of genes and alleles in a population.

Gene Flow

Movement of alleles among populations.

Genetic Drift

Random changes in allele frequencies in a population.

Founder Effect

Genetic phenomenon where a new population is established by a small number of individuals.

Population Bottleneck

Event that drastically reduces population size and genetic diversity.

Artificial Selection

Process by which humans select for desirable traits in organisms.

Speciation

Formation of new and distinct species in the course of evolution.

Biogeography

Study of the distribution of species and ecosystems in geographic space.

Comparative Morphology

Study of similarities and differences in the anatomy of different species.

Homologous Structures

Similar structures in different species that serve different functions, indicating a common ancestor.

Analogous Structures

Different structures in different species that serve similar functions but do not share a common ancestor.

Vestigial Structures

Remnants of structures that had important functions in ancestors but have lost their original function.

Divergent Evolution

Evolution in which related species become more dissimilar.

Convergent Evolution

Unrelated species develop similar traits due to similar environments.

Fossils

Preserved remains or traces of ancient organisms.

Mold Fossil

Cavity left by a decomposed organism.

Cast Fossil

Mold that has been filled with material.

Trace Fossil

Indirect evidence of an organism, such as footprints or tracks.

Transitional Fossils

Fossils that show traits common to both an ancestor and its descendants.

Pathogen

Microorganism that can cause disease.

Bacteria

Single-celled organisms treated with antibiotics.

Virus

Non-living pathogens that reproduce inside host cells.

Non-infectious Disease

Diseases caused by genetics, environmental factors, or lifestyle, not by pathogens.

First Line of Defense

Non-specific barriers that prevent pathogens from entering the body.

Second Line of Defense

Non-specific immune response that occurs when pathogens penetrate the first line of defense.

Phagocytes

White blood cells that engulf and digest pathogens.

Inflammation

Body's response to injury or infection, increasing blood flow and immune cell activity.

MHC-I Markers

Self markers present on all nucleated cells indicating they are healthy.

Antibody

Y-shaped protein produced by B cells that binds to specific antigens.

Vaccine

Preparation of killed or weakened pathogens used to stimulate antibody production for immunity.

Booster Vaccine

A follow-up vaccine that enhances or boosts immunity against a pathogen.

Herd Immunity

When a large portion of a community becomes immune to a disease, providing some protection for people who are not immune.

Disease Modeling

Using mathematical tools to describe the spread and impact of diseases.