Biology Pathway | Te Huarahi Student Lecture Book Review

Comprehensive vocabulary cards covering the fundamental concepts of biology, cell structure, metabolism, genetics, biotechnology, and ecology from the FOUN004 lecture series.

Organism

An individual living thing.

Life functions

Characteristics of living things including movement, respiration, sensitivity, growth, reproduction, excretion, and nutrition.

Cell theory

The idea summarized in four points: all living things are composed of cells, new cells form from pre-existing cells, cells contain inherited information ($genes$), and the cell is the functioning unit of life.

Autotrophic

Organisms, such as plants, that can make their own food through photosynthesis.

Heterotrophs

Organisms, such as animals, that cannot make their own food and must feed on other organisms.

Organelle

A membrane-bound, structural and functional part of the cell distinguished from the cytosol, such as the nucleus or chloroplast.

Plasma membrane

Controls what moves in and out of the cell and serves as the cell’s external surface.

Cytoplasm

The granular, watery medium between the outer plasma membrane and the nuclear envelope, containing all cellular structures.

Cell wall

A structure in plant cells made of cellulose that provides structural support.

Prokaryotic cells

Very small cells ($0.1 - 10\text{ μm}$) with no true nucleus and no membrane-bound organelles; examples include those in the Bacteria and Archaea domains.

Peptidoglycan

A polymer of protein and modified sugars found in most bacterial cell walls.

Gram-positive

Bacteria with a thick outer layer of peptidoglycan in their cell walls that affects how they stain with dyes.

Eukaryotic cells

Cells ranging from $10 - 100\text{ μm}$ that contain a nucleus separated from the cytoplasm by a nuclear membrane and have linear $DNA$.

Chitin

The material that makes up the cell wall of fungi cells.

Viruses

Acellular structures made of a core of either $DNA$ or $RNA$ and a protein coat ($capsid$); they only reproduce within the living cells of a host.

Binary Fission

The process by which prokaryotic cells reproduce by splitting in half after replicating their single circular chromosome.

Somatic cells

Body cells, such as human cells containing $46$ chromosomes.

Interphase

The period of the cell cycle consisting of $G1$, $S$, and $G2$ stages where the cell is active and replicates its $DNA$.

Mitosis

Division of the nucleus followed by cytokinesis, resulting in two identical daughter cells; stages include prophase, metaphase, anaphase, and telophase.

Cell differentiation

The process by which a single cell provides all the different tissues and organs of a multicellular organism by 'switching on' or 'off' specific genes.

Diffusion

The net movement of molecules from an area of high concentration to an area of low concentration.

Osmosis

The net movement of water from an area of high water concentration to an area of low water concentration through a semi-permeable membrane.

Hypotonic

A very weak solution of solute relative to another solution.

Hypertonic

A very strong solution of solute relative to another solution.

Active transport

The movement of substances from low concentration to high concentration across a cell membrane, requiring $ATP$; example includes the sodium-potassium pump.

Monosaccharides

Simple sugars like glucose and fructose that serve as the basic building blocks of complex carbohydrates.

Polypeptide

A molecule formed when many amino acids are linked together by peptide bonds.

Enzymes

Specialized proteins that act as organic catalysts to speed up chemical reactions by lowering the activation energy barrier.

Active site

The part of an enzyme to which a substrate is attracted and binds.

Resolution

A measure of the clarity of an image, defined as the minimum distance two points can be separated and still be distinguished.

Transmission electron microscope (TEM)

A microscope used to study internal cell structures by transmitting a beam of electrons through a very thin slice of the sample.

Nucleolus

The site within the nucleus for the transcription of ribosomal $RNA$ genes and the assembly of ribosomal subunits.

Mitochondria

Energy factories of the cell that breakdown glucose to produce $ATP$ during cellular respiration.

Endoplasmic reticulum (ER)

An extensive network of inter-connected membranes and sacs ($cisternae$); can be smooth or rough.

Photosynthesis

The process by which green plants convert light energy into chemical bond energy; expressed as $6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6 + 6O_2$.

Aerobic respiration

The process of releasing energy to support cell life using oxygen; yields up to $32\text{ ATP}$ per glucose molecule.

Glycolysis

The first anaerobic stage of respiration occurring in the cytosol where glucose is broken down into two molecules of pyruvic acid.

Complementary base pairing

The specific pairing in $DNA$ where Adenine ($A$) pairs with Thymine ($T$) and Cytosine ($C$) pairs with Guanine ($G$).

Transcription

The $DNA$-directed synthesis of $RNA$ catalyzed by the enzyme $RNA\text{ polymerase}$.

Codon

A triplet sequence of nucleotides on $mRNA$ that codes for a specific amino acid.

Translation

The process where $mRNA$ binds to a ribosome and its message is converted into an amino acid sequence via $tRNA$.

Homologous pairs

Pairs of chromosomes of the same size with genes for the same characteristics arranged in the same order, one from each parent.

Meiosis

Cell division that halves the chromosome number ($diploid$ to $haploid$) and produces genetically unique gametes.

Non-disjunction

The failure of a homologous pair to separate during gamete formation, which can lead to conditions like Down’s Syndrome ($trisomy\text{ }21$).

Genetic engineering

The manipulation of an organism’s genome using biotechnology, including artificial synthesis or modification of $DNA$.

CRISPR

A genome editing technology using palindromic repeats and the $Cas9$ protein to make precise breaks in $DNA$.

Stem cells

Undifferentiated cells that can divide to produce functional tissue, sourced from embryos, adult tissue, umbilical cords, or induced pluripotent cells.

Eco-system

A set of interacting organisms in an area together with their non-living ($abiotic$) surroundings.

Ecological niche

The specific role of a species within a community based on its adaptations.

Symbiosis

A close physical relationship between organisms in which at least one benefits, including mutualism and commensalism.