Cell and Molecular Biology

Cell Biology

Study of cell structure and function, focusing on the cell as the basic unit of life.

Cell Theory

All living organisms are composed of cells, which constitute the living unit of all organisms.

Prokaryotes

Single-celled organisms without a nucleus, including bacteria and archaea.

Eukaryotes

Organisms with a true nucleus, including plants, animals, and fungi.

George Palade

Father of Modern Cell Biology, known for using electron microscopy and discovering ribosomes.

Molecular Biology

Study of biology at a molecular level, focusing on the processes of the central dogma.

Central Dogma

The process of DNA being transcribed to RNA, which is then translated into proteins.

Natural Selection

Charles Darwin's theory explaining how traits that aid survival are passed on through generations.

Ribosome

Cellular structure responsible for protein synthesis, discovered by George Palade.

Mitosis

Process by which cells divide, leading to the formation of new cells from pre-existing ones.

Viruses

Nonliving pathogens that require a host to replicate and can contain either DNA or RNA.

Prions

Abnormal proteins that can cause neurological disorders, considered nonliving.

Morphology

Study of the form and structure of cells using various microscopy techniques.

Biochemical Techniques

Methods such as homogenization, centrifugation, and enzyme assays used to study cell components.

Unicellular

Unicellular organisms consist of a single cell, while multicellular organisms are made up of multiple specialized cells.

Chromosome Theory of Heredity

Concept that chromosomes carry genetic information and are involved in heredity.

Transgenic Organisms

Organisms that have been genetically modified to contain genes from other species.

Evolution

The process by which populations change over time through mechanisms like mutation and natural selection.

Energy Utilization

Cells acquire and utilize energy for maintenance and reproduction through processes like photosynthesis.

Functional Features of Cells

Characteristics that allow cells to acquire energy, reproduce, respond to stimuli, and self-regulate.

Zacharias Janssen

Made the 1st Compound Microscope in 1595

Robert Hooke

Coined the term “cellula” in 1655

Anton van Leeuwenhoek

coined the term “animacules” and discovered bacteria in 1674

Robert Brown

discovered the nucleus in 1833

Rudolf Virchow

stated “omnis cellula e cellula” or “every cell stems from another cell”

Rudolf Albert von Kolliker

described a powerhouse of the cell

Walther Flemming

chromosome behavior during mitosis

Richard Altman

named the powerhouse of the cell as “bioblast'“

Camilo Golgi

discovered the golgi apparatus

Carl Benda

renamed bioblast to mitochondria

Siemens

 1st commercial transmission electron microscope (TEM)

Cambridge

1st commercial scanning electron microscope (SEM)

Frederick Griffith

Transforming Principle

Phoebus Levene

identified the sugar, four nitrogenous bases and phosphate chain in a DNA

Warren Weaver

coined the name Molecular Biology

George Beadle and Edward Tatum

defined relationship between genes and proteins

Oswald Avery, Colin MacLeod, and Maclyn McCarty

DNA is the transforming principle

Alfred Hershey and Martha Chase

discovered that the genetic material is made up of DNA

James Watson and Francis Crick

discovered the double helical structure of DNA

Francis Crick

coined the term Central Dogma

Matthew Meselson and Franklin Stahl

semi-conservative DNA replication

Francois Jacob and Jacques Monod

discovered mRNA

Francis Crick, Sydney Brenner, Lesley Barnett, and R.J. Watts-Tobin

discovered the triplet codon

Marshall Nirenberg and Heinrich Matthaei

cracked 54 codes out of the 64 codons

Domain Archaea

Methanogens, Halophiles, Acidophiles, and Thermophiles

Domain Bacteria

smallest known cells - mycoplasma; eubacteria (true bacteria) and cyanobacteria (blue-green algae)

Cell Wall

A non-living and rigid coat that surrounds plant cells.

PLasmalemma

Also called cell membrane; made up of phospholipid bilayer, with protein molecules scattered all over.

Mitochondria

was first seen by Kollicker in 1850 in muscles and called then ‘sarcosomes’

Cristae

is the folding of the inner mitochondrial membrane that allows more surface area, enhancing its ability to produce ATP.

Chloroplast

found only in plant cells and plant-like protists; contains chlorophyll and carry out photosynthesis.

Rough Endoplasmic Reticulum

studded with ribosomes; site of synthesis of many proteins.

Smooth Endoplasmic Reticulum

site for synthesis of steroids and other lipids; Ca++ storage in muscles; detoxification of drugs, toxins, alcohol.

Golgi Complex

consists of 3 to 20 cisternae; modification of proteins and lipids; storage and packaging of molecules; THE POST OFFICE OF THE CELL

Ribosome

Protein synthetic machinery

Lysosome

vesicles filled with digestive enzymes - used for intracellular digestion

Vacuole

Membrane-bound sac; storage container for water, food, enzymes, wastes, pigments, etc.

Centriole

part of specialized region of the cell called centrosome; found in animals and most protists and involved in the production of microtubules.

Cytoskeleton

A network of protein filaments that extends throughout the cytoplasm.

Microtubules

Long, hollow, unbranched, polar cylinders, made up of protein “tubulin”.

Intermediate Filaments

Polymers of long rod-like proteins. These filaments are thicker than microfilaments but thinner than microtubules. Provide mechanical support to the cell, helps in intercellular attachment, provide strength and rigidity to neurons, and major structural role in skin and hair cells.

Microfilaments

Thinnest elements of the cytoskeleton. Composed of the protein actin. Form a meshwork under plasma membrane.

Perixosome

Also known as microbodies; create H2O2 as a byproductt and degrade it with the enzyme catalase. It oxidizes amino acids, oxidizes long chain fatty acids, and protects cells from the toxic effects of H2O2.

Nucleus

Control center of the cell; has the information needed to oversee the chemical reaction of the cells.

Nucleolus

Ribosome factory; large, prominent structures without membrane