CH1 The Cell
1.Prokaryotes
a. No organelles
b. No distinct nucleus
c. Single circular chromosome instead of double DNA
d. Singles celled
e. Cyanobacteria, rickettsiae, bacteria
f. No nuclear membrane
g. Lack a distinct nucleus (more than one)
h. The nuclei carry genetic info in a single circular chromosome
i. Lack histones
i. Histones allow supercoiling of DNA
2.Eukaryotes
a. Animals and plants, protozoa, fungi, most algae
b. Larger with organelles
c. Nucleus is defined
i. Contains DNA and control genetic and cell divison
d. Cells bind with DNA
e. Ribosomes attach to ER rough
i. Cellular protein synthesis
f.
,3.Cellular Functions
a. Cells go through differentiation or maturation so that some cells perform one kind
of function and other cells perform other functions
b. Cells with highly developed function such as movement lack other functions
c. Movement- muscle cells can move limbs
d. Conductivity- electrical impulse that reaches to other body parts neurons
e. Metabolism- take in and use nutrients ALL CELLS
f. Secretion- such as mucous gland can secrete substance
g. Excretion- rid of waste products ALL CELLS
h. Respiration- absorb oxygen which is used to transform nutrients into energy
i. Reproduction- new cells replace dead cells
i. Heart cells, skeletal cells, and neurons cant reproduce
j. Communication
4.Nucleus
a. LARGEST ORGANELLE
b. Nuclear envelope has pits called nuclear pores which allow chemical messages
to enter and exit the nucleus
c. Nucleolus is a small structure composed of ribonucleic acid
d. DNA is so long it can break so..
e. Histones are DNA binding proteins that make DNA fold into chromosomes which
decrease the risk of breakage
5.Plasma Membranes
a. Membranes allow control the movement of molecules
b. Phospholipid bilayer
i. Head = hydrophilic and polar so negative charge <3
ii. Tail = hydrophobic and nonpolar no charge
c. Cell polarity- the direction of cellular transport maintains normal cell structure
d. Cell to cell recognition and maintain shape
e. Membrane composition
f. Lipid bilayer is the basic structure
g. Lipid and protein are the main constituents of membrane
h. The membrane organization is achieved through NONCOVALENT bonds which
allow different phases (solid gel, liquid crystalline, liquid ordered phase)
i. Phases can change under temp and pressure
j. Lipids
i. Each lipid is amphipathic one part is hydrophobic and hydrophilic
ii. The bilayer serves as a barrier to allow oxygen and carbon to diffuse
through (lipid soluble ONLY)
1. Only small molecules allow to pass thru
, 2. Proteins allow larger molecules to pass
iii. Phospholipids are most abundant
iv. Lipids along with protein assemblies act as “molecular glue”
k. Proteins
i. Made of chains of amino acids called polypeptides
ii. Posttranslational modifications (PTMS) methods used to diversify the
limited numbers of proteins generated
1. Alter the activity and functions of proteins
2. Important in understanding disease
iii. Proteome are the entire set of proteins expressed by a genome
iv. Integral membrane proteins detergents that remove bilayer by DISSOLVE
v. Peripheral membrane proteins gentler method that remove protein but DO
NOT DISSOLVE
vi. Protein functions
1. Recognition and binding units
2. Transport channel Acts as pores for transport of ions
3. Acts as enzymes that drive pumps
4. Cell surface markers for glycoproteins : proteins attached to carb
5. Cell adhesion molecules allow ells to hook together to maintain
shape
6. Catalysts of chemical reaction
vii. Proteostasis protein homeostasis comprised of
1. ribosomes (makers)
2. Chaperones (helpers)
3. Two protein breakdown systems proteolytic systems
l. Carbohydrates
i. Short chain of sugar oligosaccharides
ii. Proteoglycans long polysaccharide chains attached to membrane proteins
iii. All carbs are located OUTSIDE of membrane
iv. Glycocalyx helps protect and coat the cell from damage
v. Carbs play a role in recognition
6.Cellular receptors
a. Protein in cytoplasm or nucleus that can bind with smaller molecules called
ligands (ex. hormones)
b. Binding depends on chemical configuration (noncovalent interactions,
hydrophobic forces)
c. Ligands job is to signal by binding to receptor cell
i. If ligand binds to white blood cell it will signal to fight
7.Cell to Cell Adhesion
a. How can cells be connected strongly???
1.Prokaryotes
a. No organelles
b. No distinct nucleus
c. Single circular chromosome instead of double DNA
d. Singles celled
e. Cyanobacteria, rickettsiae, bacteria
f. No nuclear membrane
g. Lack a distinct nucleus (more than one)
h. The nuclei carry genetic info in a single circular chromosome
i. Lack histones
i. Histones allow supercoiling of DNA
2.Eukaryotes
a. Animals and plants, protozoa, fungi, most algae
b. Larger with organelles
c. Nucleus is defined
i. Contains DNA and control genetic and cell divison
d. Cells bind with DNA
e. Ribosomes attach to ER rough
i. Cellular protein synthesis
f.
,3.Cellular Functions
a. Cells go through differentiation or maturation so that some cells perform one kind
of function and other cells perform other functions
b. Cells with highly developed function such as movement lack other functions
c. Movement- muscle cells can move limbs
d. Conductivity- electrical impulse that reaches to other body parts neurons
e. Metabolism- take in and use nutrients ALL CELLS
f. Secretion- such as mucous gland can secrete substance
g. Excretion- rid of waste products ALL CELLS
h. Respiration- absorb oxygen which is used to transform nutrients into energy
i. Reproduction- new cells replace dead cells
i. Heart cells, skeletal cells, and neurons cant reproduce
j. Communication
4.Nucleus
a. LARGEST ORGANELLE
b. Nuclear envelope has pits called nuclear pores which allow chemical messages
to enter and exit the nucleus
c. Nucleolus is a small structure composed of ribonucleic acid
d. DNA is so long it can break so..
e. Histones are DNA binding proteins that make DNA fold into chromosomes which
decrease the risk of breakage
5.Plasma Membranes
a. Membranes allow control the movement of molecules
b. Phospholipid bilayer
i. Head = hydrophilic and polar so negative charge <3
ii. Tail = hydrophobic and nonpolar no charge
c. Cell polarity- the direction of cellular transport maintains normal cell structure
d. Cell to cell recognition and maintain shape
e. Membrane composition
f. Lipid bilayer is the basic structure
g. Lipid and protein are the main constituents of membrane
h. The membrane organization is achieved through NONCOVALENT bonds which
allow different phases (solid gel, liquid crystalline, liquid ordered phase)
i. Phases can change under temp and pressure
j. Lipids
i. Each lipid is amphipathic one part is hydrophobic and hydrophilic
ii. The bilayer serves as a barrier to allow oxygen and carbon to diffuse
through (lipid soluble ONLY)
1. Only small molecules allow to pass thru
, 2. Proteins allow larger molecules to pass
iii. Phospholipids are most abundant
iv. Lipids along with protein assemblies act as “molecular glue”
k. Proteins
i. Made of chains of amino acids called polypeptides
ii. Posttranslational modifications (PTMS) methods used to diversify the
limited numbers of proteins generated
1. Alter the activity and functions of proteins
2. Important in understanding disease
iii. Proteome are the entire set of proteins expressed by a genome
iv. Integral membrane proteins detergents that remove bilayer by DISSOLVE
v. Peripheral membrane proteins gentler method that remove protein but DO
NOT DISSOLVE
vi. Protein functions
1. Recognition and binding units
2. Transport channel Acts as pores for transport of ions
3. Acts as enzymes that drive pumps
4. Cell surface markers for glycoproteins : proteins attached to carb
5. Cell adhesion molecules allow ells to hook together to maintain
shape
6. Catalysts of chemical reaction
vii. Proteostasis protein homeostasis comprised of
1. ribosomes (makers)
2. Chaperones (helpers)
3. Two protein breakdown systems proteolytic systems
l. Carbohydrates
i. Short chain of sugar oligosaccharides
ii. Proteoglycans long polysaccharide chains attached to membrane proteins
iii. All carbs are located OUTSIDE of membrane
iv. Glycocalyx helps protect and coat the cell from damage
v. Carbs play a role in recognition
6.Cellular receptors
a. Protein in cytoplasm or nucleus that can bind with smaller molecules called
ligands (ex. hormones)
b. Binding depends on chemical configuration (noncovalent interactions,
hydrophobic forces)
c. Ligands job is to signal by binding to receptor cell
i. If ligand binds to white blood cell it will signal to fight
7.Cell to Cell Adhesion
a. How can cells be connected strongly???
