Exam 1 Study Guide
Needed in order to look at cells that are smaller than can be detected by human senses (super tiny or super large).
Can limit the progress of science (We must know its limitations.)
Fluorescence microscopy is a form of light microscopy
Transmission electron microscopy (TEM) provides a thin, twodimensional section of the object being studied.
Cell Culture Technique Limitations:
o Not all cells will grow in culture.
o Cells lose their histotype (in vivo shape) and 3D structure of tissue is changed. o Metabolism likely changes.
AnchorageDependent for Growth (stops growing when there is no more space)
AnchorageIndependent for Growth (continues to grow whether there is space or not)
Even if they are crowded by surrounding cells, the will become spherical and can still go through cell division.
Paramecium (a singlecelled eukaryotic cell) We also discuss several other topics like What was the modern synthesis in biology and who played a role in it?
Don't forget about the age old question of anthropology exam
swims by way of cilia
has a very limited number of biomolecular machines in it.
o Cannot do more complex functions because it can only do one thing at a time has to do everything for itself: find food, find shelter, find a mate, and reproduce o also must escape from predators Don't forget about the age old question of ensonhs
contractile vacuole: possibly a precursor to the kidney
Division of Labor:
in multicellular organisms only (not singlecelled)
every cell doesn’t have to do everything
cells with different functions have the same DNA
Lymphocytes, Macrophages, and Fibroblasts are not responsible for finding food.
Loss of the Cell Wall:
The presumed step of the transition from primitive protoprokaryotic cell to primitive protoeukaryotic cell.
Required for both the endosymbiotic theory and the endomembrane theory. DNA in extant prokaryotic cells is circular.
The outer boundary of life in an extant prokaryotic cell is the capsule.
The cytoskeleton enabled the primitive cell to become motile.
Flexible surface (loss of cell wall) allowed cell to exchange materials with environment. Ribosomes are bound to some of the membrane invaginations in the endomembrane theory.
Gave rise to the endoplasmic reticulum and Golgi apparatus.
Origin of the mitochondria (makes ATP) and chloroplasts
Mitochondria was likely sitting somewhere doing its thing when the eukaryotic cell came up and was likely low on ATP. The mitochondria was then likely enveloped and started using some of the ATP it was producing.
After a cell is pancake shaped in a cell culture dish, the order of events that occurs as a cell walks is: filapodia, lamellipodia, cell muscle, retraction fiber.
The end of the retraction fiber touching the cell culture plate still contains the cell equivalent of super glue. We also discuss several other topics like looking at movies chapter 1
It is presumed that the peroxisomes evolved in these primitive, protoeukaryotes to remove oxygen, which was toxic to these primitive cells. (The ancient earth did not contain much oxygen.)
The surface area to volume ration limits how big a cell can be.
The ER is contiguous with the nuclear envelope & the Golgi apparatus. If you want to learn more check out mis exam 1
The vesicles are carried from the Golgi apparatus to the plasma membrane on the microtubule system. The microtubule system never touches the outer membrane. Then, it is transferred to the actin filament network to help the vesicle to be pushed out of the cell.
Cholesterol is good to have in biological membranes.
Active Transport: uses ATP to move components against their concentration gradient. We are made up of 5070% water.
Facilitated Diffusion: uses a channel protein to let components move down their concentration gradient.
KNOW HOW TO DRAW A PHOSPHOLIPID
Functions of a Membrane:
1) To partition water (and things soluble in water)
2) To compartmentalize enzymes to increase the efficiency of chemical reactions (enzymes will be in order in the cell. If you want to learn more check out llcc blackboard
Two kinds: essential amino acids (your body cannot make them) and nonessential amino acids (your body can make them).
It is not a simple matter for a vesicle to form from the endoplasmic reticulum.
For a protein to enter the endoplasmic reticulum as part of the endoplasmic reticulum’s lumen or part of the endoplasmic reticulum’s membrane, a ribosome binds to the mRNA and a short stretch of protein is synthesized that contains a signal sequence.
The plasma membrane gets new lipids from the lumen of the ER.
Triglyceride vs. Phospholipid:
A triglyceride has 3 fatty acids vs. a phospholipid that has 2 fatty acids. A phospholipid also has a hydrophilic head.
Only multipass TMPs can make a channel (not singlepass)
Geography of Systems in a Cell:
Actin filaments: cell cortex (edge of cell)
Microtubules: cell interior (reaching all across the cell)
o Two H2A
o Two H2B
o Two H3
o Two H4
One H1 staples the wrapped DNA to the nucleosomal cores after the DNA wraps around each core 1 and 3/4th times
Actin Filament System:
Does not extend outside the cell.
Not present in the nucleus.
Intermediate Filament System:
Lines the inside of the nucleus to protect it and add strength.
Run on the actin filament system and the microtubule system (not on the intermediate filament system)
Use ATP as the energy source to power the molecular motors.
Naked DNA does not exist in nature, but scientists can make naked DNA in a test tube. Chromosomes are made of heterochromatin (enzymes can’t get in)
Heterochromatin DOES exist during interphase (the resting state that a nucleus is usually in.
Diameters of Filaments:
Actin Filaments: 7 nm
Microtubules: 25 nm
Intermediate Filaments: 10 nm
Cilia and microvilli do not contain a similar number of parallel actin filaments. (Cilia are made with microtubules)
To get into the nucleus, a component has to have the correct signal sequence and pass through a nuclear pore.