Lecture 13 Flashcards
What does it take to make a cell?
Information, chemistry, compartments
What is information within a cell?
DNA
What do all cells posses?
DNA - the hereditary material of genes and RNA - which provides the information necessary to build various proteins (enzymes, channels, receptors)
What occurs during DNA replication?
Information is transferred from one DNA molecule to the other.
What occurs during transcription?
Information is transferred from DNA to an RNA molecule.
What occurs during translation?
Information is transferred from RNA to a protein through a code that specifies the amino acid sequence.
Glia Cells
a non neuronal brain cell type
Red Blood Cells
cell delivering oxygen to body tissues
Osteoblasts
Cells that makes bones
Corneal Keratocytes
Cells that make the transparent front part of the eye.
What cell type lacks a nucleus and therefore has no DNA?
Mature red blood cells do not contain DNA and cannot synthesis any RNA, therefore it cannot divide and repair.
What is Enucleation?
Mechanism by which maturing red blood cells (erythrocytes) eject their nucleus.
Differentiation?
The process during development in which multicellular organisms become specialized
What is an example of differentiation?
A stem cell turning into a sex cell, fat cell, bone cell, etc.
What are the building blocks of life?
Amino acids, lipids and nucleic acids
What is the Miller-Urey Experiment?
Chemical experiment that stimulated the conditions thought to exist on early earth and to test the chemical origin of life under those conditions.
What is Oparin’s and Haldane’s primordial soup hypothesis?
Putative conditions on the primitive earth favoured chemical reactions that synthesized more complex organic compounds from simple organic precursors
What does the chemical origin of life equal?
Abiogenesis (compound - nitrogen, ammonia, methane, water + energy = single organic compound)
What does the first group of intermediate products (ex. formaldehyde hydrogen cyanide) + energy produce?
Second group of intermediate products (urea, formic acid, amino acids)
What can amino acids be generated in?
Conditions that mimic those of the early Earth
What can other chemical reactions generate?
Simple sugars, the bases found in nucleotides and the lipids needed to form primitive membranes
What is a compartment?
A single or double lipid layer membrane
What are examples of cellular compartments?
Mitochondria, chloroplasts, the cell nucleus, vesicles and endoplasmic reticulum.
What are some fundamental roles that compartments play a role in?
Establishing physical boundaries that enable the cell to carry out different metabolic activities.
Generate a microenvironment to spatially and temporally regulate biological processes.
Who was Robert Hooke?
An English scientists who contributed to the improvement of the microscope and explored the structure of snowflakes, fleas, lice and plants.
Who are the two scientists credited for the Cell Theory?
Matthias Jakob Schleiden and Theordor Schwann
What are the three tenets of Cell Theory?
- All living organisms are composed of one or more cells
- The cell is the most basic unit of life.
- All cells arise ONLY from pre existing cells
What are the basic properties of cells?
Highly complex and organized
Activity controlled by a genetic program
Can reproduce
Assimilate and utilize energy
Carry out chemical reactions (enzymes)
Engage in mechanical activities
Respond to stimuli
Capable of self-regulation
They evolve
Prokaryotes
Single cell organisms that lack a defined nucleus
- Divided into Archaea and Bacteria
What is the size of a prokaryote?
1 - 10 microns
What are some characteristics of a Prokaryotic cell?
- No nucleus or organelles
- Ribosomes are present but small
- Reproduce asexually
- Genetic material nucleoid
What are organisms that have eukaryotic cells?
Protoza, Fungi, plants and animals
What is the size of a eukaryotic cell?
Typically around 10 - 100 microns
What are some characteristics of Eukaryotic cells?
Ribosomes are large
Nucleus and organelles
Genetic material found in nuclear compartment and arranged as chromosomes
What is only found in animal cells?
Lysosomes and Microvilli
What is only found in plant cells?
Cell walls, vacuoles, chloroplasts and plasmodesmata
