APPLICATIONS ACCESS Biology - Practice Practice

Flashcards based on a comprehensive biology transcript covering cellular structure, metabolic pathways, heredity, ecosystems, human anatomy, and evolutionary biology.

Bioelements

The basic chemical elements of living matter, where carbon, oxygen, hydrogen, nitrogen, phosphorus and sulphur make up about $99\%$ of all living beings.

Virus Visibility

Biological structures that can only be observed with an electron microscope.

Chitin

The main component of the cell wall of fungi (mushrooms).

Peptidoglycans

The main component of the cell wall of bacteria.

Cellulose

The main component of the plant cell wall.

Eukaryotic Cell Diameter

The average size typically ranging between $10-100\,\mu m$.

Prokaryotic Cell Diameter

The average size typically ranging between $0.5-5\,\mu m$.

Nucleoid

The structure in the cytoplasm of a prokaryotic cell where the DNA is located.

Prokaryotic Ribosomes

Composed of two subunits, $50S$ (major) and $30S$ (minor), with a total sedimentation coefficient of $70S$.

Eukaryotic Ribosomes

Composed of two subunits, $60S$ (major) and $40S$ (minor), with a total sedimentation coefficient of $80S$.

Golgi apparatus

The cellular structure responsible for the sorting and modification of neo-synthesised products from the endoplasmic reticulum.

Lysosomes

Vesicles containing hydrolytic enzymes responsible for breaking down, digesting, and recycling molecules and materials hazardous to the cell.

Biological Catalysts

Enzymes that lower the activation energy of a chemical reaction, thereby accelerating the process.

Extrachromosomal Genome

Genome found within specific organelles such as mitochondria and chloroplasts.

Capside

General term for the protein structure/envelope present in 'naked' viruses.

Selective Permeability

The characteristic of the cell membrane that allows it to act as a barrier regulating the traffic of ions and molecules.

Osmosis

A flow of solvent between two solutions of different concentrations separated by a semi-permeable membrane.

Symport

A type of active transport that allows the simultaneous passage of two substances in the same direction.

Antiport

A type of active transport that allows two different substances to pass simultaneously in opposite directions.

Interphase

The phase of the cell cycle that separates two mitotic divisions.

Karyokinesis

The process commonly referred to as the nuclear division of cells (mitosis).

Cytopheresis

The process of division of the cytoplasm that normally follows mitosis.

Prophase

The stage of mitosis in which chromatin condenses into chromosomes.

Metaphase

The stage of mitosis in which chromosomes align along the equatorial plate.

Anaphase

The stage of mitosis in which sister chromatids separate.

Telophase

The stage of mitosis in which the nuclear membrane is reformed.

Crossing-over

The mutual exchange of DNA segments between homologous chromosomes occurring during prophase I of meiosis.

Prometaphase

The stage of mitosis in which the nuclear membrane dissolves completely and chromosomes attach to the spindle.

S Phase

The specific part of the cell cycle where DNA synthesis occurs.

Primary Structure of Proteins

The linear sequence of amino acids linked by peptide bonds.

Secondary Structure of Proteins

Structural levels including Alpha-helices and beta sheets.

Peptide Bonding

Covalent bonding specifically between two amino acids.

Apoptosis

The biological process defined as programmed cell death.

Necrosis

Unplanned cell death caused by cellular trauma.

Glia cells

Cells belonging specifically to the nervous tissue.

Pericardium

The external serous membrane that covers and protects the heart.

Triglycerides

Lipid molecules composed of one molecule of glycerol and 3 of fatty acids.

Endocrine Glands

Glands such as the thyroid or pituitary that produce and release hormones directly into the bloodstream.

Insulin

A hormone produced by the beta cells of the pancreas that functions in reducing blood glucose.

Glucagon

A hormone produced by the alpha cells of the pancreas that functions in increasing blood glucose.

Cortisol

The hormone commonly referred to as the 'stress hormone'.

Nociceptors

Sensory receptors specialized for the perception of pain.

Proprioceptors

Receptors such as Pacini, Meissner, and Merkel corpuscles associated with tactile sensation.

Filtration

The main transport mechanism involved in the formation of renal filtrate in kidney nephrons.

Trophic Level

The position of an organism within a food chain; example: herbivores occupy the primary level.

Genetic Drift

The variation of allele frequencies in a population determined by random events, most frequent in small populations.

Founder Effect

An example of genetic drift resulting in a loss of genetic variability when a new population is established by a few individuals.

Mendel's First Law

The law of segregation, stating that hybrids of two pure lines all show the dominant character.

Mendel's Second Law

The law stating that during gamete formation, alleles of a gene separate so each gamete receives one copy.

Mendel's Third Law

The law of independent assortment, stating that alleles of different genes separate independently during gamete formation.

Periosteum

A connective membrane that adheres to the outer surface of all skeletal segments.

Epiphysis

The end part of long bones, composed mainly of spongy bone tissue.

Diaphysis

The central part of long bones, containing compact bone tissue.

Haemopoietic Bone Marrow

Bone marrow having the function of generating blood cells.

Ubiquitination

The biological mechanism that enables proteasomal degradation of proteins.

Glycolysis

Process occurring in the cytoplasm where one glucose molecule is split into two pyruvate molecules, consuming $2\,ATP$ and producing $4\,ATP$ (net gain: $2\,ATP$).

Systemic Circulation

Circulation originating in the left ventricle that brings oxygenated blood to the tissues.

Pulmonary Circulation

Circulation that pumps carbon dioxide-rich blood from the right ventricle into the pulmonary artery.

Non-overlapping Code

A characteristic of the genetic code where ribosomes proceed from triplet to triplet without shared bases.

Plasmids

Circular extrachromosomal DNA molecules present in bacteria containing genes that often confer characteristics useful for survival.

Transcription

The biological process leading to the formation of an RNA molecule from a DNA template.

Translation

The cellular process by which mRNA is decoded to synthesise specific proteins.

Barr's bodies

Condensed X chromosomes in heterochromatin found in female mammalian individuals.

Stomata

Specialised openings in the leaves and herbaceous stems of plants for gas exchange.

Ptyalin

A digestive enzyme found in the mouth that breaks down starch.

RuBisCo

The enzyme responsible for carbon fixation during the Calvin cycle in photosynthesis.

Calvin Cycle

The light-independent phase of photosynthesis occurring in the stroma of the chloroplasts.

Ginglims

Variants of joint sutures categorized into corner and side types.

Convergent Evolution

Mechanism where different species independently develop similar structures, such as wings in bats and birds.

Totipotente Stem Cells

Stem cells able to differentiate into all cell types and give rise to a complete organism.

Pluripotent Stem Cells

Stem cells able to differentiate into all cell types present in the body but cannot produce a complete organism.