Cell Biology Exam 1
The foundations of biology were laid in the 1600s by a scientist named __________ __________.
What did Robert Hooke use in his experiment were he discovered cells?
Thin slices of cork
Why did Hooke use the word cell to name what he observed?
The structures reminded him of the cells inhabited by monks living in a monastery. He originally named them cellulae
Antony van Leeuwenhoek was the first person to describe __________ __________.
What did Leeuwenhoek name the specimen he was studying?
Leeuwenhoek was also the first person to see human __________.
What are three reasons why advances in studying cells was limited until the 19th century?
Technology wasn't invented yet for the following:
1. Tissue preparation (stabilizing tissue to preserve it for further study)
2. Sectioning and staining ( Thin sliced tissue to observe cell structures)
(Used to use wax to prepare slides)
3. Better optics (oil immersion)
What two things did Dutrochet discover in 1824?
1. Animals and plants are both aggregates of cells.
2. Growth results from an increase in cell size, cell number, or both
What did Robert brown discover?
Every plant cell he studied contained a round structure which he called a nucleus.
Matthias Schleiden studied plant tissue and Theodor Schwann studied animal cells and together they proposed the first two tenets of the __________ __________.
What are the three tenets of the cell theory?
1. All organisms are composed of one or more cells
2. The cell is the basic unit of structure for all living organisms
3. Cells can arise only by division of preexisting cells
Who derived the last tenet of the cell theory?
What two changes in thinking arose from the progress in the 19th century?
1. Before Virchow cells were considered to be only structural. Virchow defined disease as an aberration in normal cell processes.
2. "Long ago it became evident that the key to every biological problem must be sought in the cell: for every living organism is, or at some time has been a cell." -E.B. Wilson
What three disciplines developed into cell biology?
What is Cytology?
The study of cell structure
Cytology began in the 1600s with __________ and __________.
Hooke and Leeuwenhoek
Advances in __________ __________ and __________ __________ led to progress in cytology.
What is Biochemistry?
The study of chemical processes within and relating to living organisms.
What did Friedrich Wohler do?
He synthesized urea in 1828 which is a major component of urine. Before this, people believed that chemicals made by our bodies could not be synthesized in a lab. Organic chemicals became less of a mystery.
What did Justus Von Liebig believe?
He believed that alcoholic fermentation was catalyzed by non-living enzymes. (Vitalists believed that the enzymes "yeast" had to be alive)
What did Louis Pasteur believe?
He believed that live yeast was needed for fermentation
What did Eduard Buchner find?
He found that yeast can be dead and still ferment alcohol
What is Genetics?
The study of genes, genetic variation, and heredity in living organisms
Genetics began with __________ __________.
what did Friedrich Miescher discover?
Working in a hospital he studied puss.
What did Walther Flemming identify?
What did Wilhelm Roux and August Weissman suggest?
That chromosomes bear genetic information
What did Walter Sutton formulate?
The chromosomal theory of heredity
What is the difference between positive and negative staining?
Positive staining - Stain the things your interested in looking at.
Negative staining - Stain the things your not interested in looking at.
Cells can vary in size from __________ -----> __________
(Marine Algea) (Eggs)
The shape of cells is related to their __________ and __________.
What problems do cells face with their surface area to volume ratio?
- What is one way to fix this?
- As the cell increases in size the surface area can't keep up with the pace of the volume.
- Creating folds in the membrane to increase surface area
Cells have the potential for independent __________.
(they can be grown in the lab)
All cells get energy from what?
Light or food using metabolic machinery that they possess
The energy that cells collect supports what?
Essential life processes
- cell division, movement of stuff around the cell
- Molecular transformations - replace worn out parts
All cells need genes as a __________ for the synthesis of the structures they build.
All cells need a __________ __________.
(A boundary between them and the outside world)
All cells exhibit compartmentalization what does this mean?
Allows cells to maintain locally high concentrations of some substances
Prokaryotes include what cells?
Blue green algae
Eukaryotes includes what cells?
Prokaryotes contain Flagella. What are these?
Protein strands wound like rope and anchored to the cytoplasm that whip for mobility of the cell
Prokaryotes contain Pili. What these?
Fine projections that help with movement and conjugation (exchange DNA between bacteria)
What covers the outside of the cell membrane in prokaryotic cells?
A capsule needed to protection
The cell wall in blue green algea is mainly composed of __________.
The cell wall in bacteria is mainly composed of __________ __________.
The cell wall makes up __________ - __________ % of the cell's dry weight.
__________ is what is left over after you completely remove the cell wall of a cell.
__________ is what is left over after you partially remove the cell wall of a cell.
What is the function of the cell membrane?
It controls what goes in and out of the cell
Prokaryotes contain lamellae. What is this?
Infolded membrane to increase the surface area for photosynthesis
Prokaryotes contain mesosomes which do what?
Help during bacterial fission to separate the two circular chromosomes
Ribosomes come in two parts what are they called?
Small ribosomal subunit
Large ribosomal subunit
What do ribosomes do?
Bacteria contain granular inclusions. What are these?
Storage sites for nutrients and fat
In prokaryotes DNA is located in the __________.
What are the three domains of life?
Which of the three domains is prokaryotic and which is eukaryotic?
Bacteria - Prokaryotes
Archea - Prokaryotes
Eukarya - Eukaryotes
Cell wall is made of __________ or __________
maintains integrity a controls what gets in and out of the cell. made of a lipid bilayer
Nucleus has a __________ membrane
Storage location of genetic information
Chromatin consists of what three things?
Where is most of the cell RNA?
In the cytoplasm
Where ribosomal RNA is synthesized. Not membrane bound