BM1110 Lectures 2 - 8

Scientific Method

A systematic approach used to conduct scientific research, ensuring rigor and reproducibility through controlled experimentation.

Positive Controls

Experiments designed to ensure that the experimental conditions and reagents are functioning correctly, thus eliminating false negatives.

Negative Controls

Experiments that give a baseline effect to ensure observed effects are only due to the parameter being tested, eliminating false positives.

Cell Theory

A fundamental principle stating that all living things are made of cells, cells are basic units of life, and cells can only arise from other cells.

Microscopy

The use of microscopes to observe small objects, with important terms including magnification and resolution.

Magnification

The increase in the specimen's apparent size when viewed under a microscope.

Resolution

The ability of an instrument to show two distinct objects as separate.

Eukaryotic Cells

Cells that possess membrane-bound organelles and a nucleus, such as those found in humans, plants, and fungi.

Prokaryotic Cells

Cells that lack a nucleus and organelles, such as bacteria.

Phospholipid Bilayer

A double layer of phospholipids that forms the core structure of cell membranes.

Nucleus

The largest organelle, containing the DNA and the nucleolus, involved in gene expression and ribosome synthesis.

Mitochondria

Organelles known as the 'powerhouses' of the cell, responsible for ATP production through cellular respiration.

Chloroplasts

Organelles in plant cells that carry out photosynthesis, converting light energy into chemical energy.

Fluid Mosaic Model

A model describing the membrane structure as a mosaic of various components that move freely.

Active Transport

The movement of substances across a membrane against their concentration gradient, requiring energy input.

Facilitated Diffusion

Passive transport of molecules across a membrane via membrane proteins.

Endocytosis

The process by which cells transport substances into the cell by enveloping them in membrane.

DNA Structure

The double helix structure of DNA composed of two strands that run antiparallel and are held together by base pairing.

Chargaff’s Rule

The principle that states in DNA, the amount of adenine equals thymine and the amount of guanine equals cytosine.

DNA Replication

The process by which DNA is copied, resulting in two identical DNA molecules.

Gene Regulation

The mechanisms that control the expression of genes and how much of a given protein is produced.

Transcription Initiation

The process by which transcription factors and enhancers help form the initiation complex to begin mRNA synthesis.

Post-Translational Modifications

Chemical modifications made to proteins after translation, influencing their activity and function.

Cell Membrane

A selectively permeable barrier that regulates the entry and exit of substances in and out of the cell.

Cytoplasm

The gel-like substance within the cell membrane where organelles are suspended, facilitating cellular processes.

Ribosomes

Molecular machines within the cell that synthesize proteins by translating messenger RNA.

Lysosomes

Organelles that contain digestive enzymes to break down waste materials and cellular debris.

Endoplasmic Reticulum (ER)

An organelle involved in the synthesis of proteins (rough ER) and lipids (smooth ER), and transport within the cell.

Golgi Apparatus

An organelle that modifies, sorts, and packages proteins and lipids for secretion or delivery to other organelles.

Cytoskeleton

A network of fibers that provides structural support, maintains cell shape, and facilitates cell movement.

Apoptosis

The process of programmed cell death that is a normal part of growth and development.

Stem Cells

Undifferentiated cells with the potential to develop into various cell types and self-renew.

Biotechnology

The use of living systems and organisms to develop or create products, often involving genetic manipulation.

Cellular Respiration

The metabolic process by which cells convert glucose and oxygen into energy, carbon dioxide, and water.

Photosynthesis

The process in which plants convert light energy into chemical energy, producing glucose and oxygen from carbon dioxide and water.

Homeostasis

The ability of an organism to maintain a stable internal environment despite external changes.

Mutations

Changes in the DNA sequence that can lead to alterations in protein function and may result in genetic diversity or disease.

Protein Synthesis

The process by which cells use mRNA, tRNA, and ribosomes to produce proteins based on genetic instructions.

Genome

The complete set of genetic material within an organism, encompassing all of its genes.

Chromosomes

Structures made of DNA and protein that contain genetic information, found in the nucleus of eukaryotic cells.

Transcription

The process of copying a segment of DNA into messenger RNA (mRNA) prior to translation.

Translation

The process by which ribosomes synthesize proteins using the encoded information in mRNA.

Antibodies

Proteins produced by the immune system to identify and neutralize foreign objects like bacteria and viruses.