CHEE 370 2.1

What are the 3 attributes of all living things

1. Catalysis - extract energy form nutrients

2. Mutability - respond to changes in the environment

3. Replication - ability to grow, differentiate, and reproduce

3 Principles of Modern Cell Theory

1. all living things are made from cells

2. the cell is the smallest living unit in all organisms

3. all cells come from other pre-existing cells

Why must cells always be in a state of inbalance with thier environmen?

in order to perform functions such as replication, catalysis, and mutability

Cytoplasmic Membrane

Separates cell content from environment and controls transport in or out, maintains electrochemical imbalance

Main difference between prokaryotes and eukaryotes?

eukaryotes are compartmentalized

Size of virus, prokaryote, vs eukaryotes

virus<prokaryote<eukaryote

what are cells primarly composed of by weight?

water then proteins then nucleic acid

what do proteins do

perform functions like catalysis, structure, and transport

what does nucleic acid do

stores and transmits genetic information needed to make proteins

3 key feature of prokaryotes

1. 70nm thick membrane

2. 30-350 nm thick cell wall of polysaccarides

3. can have flagella for locomotion

How is memory DNA stored in prokaryote?

a single circular chomosome loated in the nucleoid

How do prokaryotes divide

asexual seperation into two (binary fission) or more (multiple fission) cells

What are plasmids

small, DNA molecule separate from the main bacterial chromosome that can carry additional genes and be more easily exchanged between cells

why can plasmids provide an evolutionary advantage?

can carry and tranfer useful genes, like antibiotic resistance between cells

prokaryotes doubling time

20 min - an hour

shapes of prokaryotes

1. spherical (cocci)

2. rod-like (baccilli)

3. spiral (spirilla)

what is the most common bacteria used for studies and why?

e.coli is used to study proteins, amplify recombinant plasmids, and industrially produce proteins

size of eukaryotes

10-100 micrometers

What type of chromosomes do eukaryotic cells have?

A discrete number of linear chromosomes.

How does the amount of genetic information in eukaryotes compare with prokaryotes?

Eukaryotes generally contain much more genetic information.

How do eukaryotic cells divide?

By mitosis or meiosis.

How do eukaryotic and prokaryotic growth rates generally compare?

Eukaryotic cells generally grow and divide more slowly than prokaryotic cells (few hours to years.

What is the plasma membrane?

A delicate double layer of lipids and proteins that separates the inside of the cell from the outside environment and controls what enters and exits.

3 functions of membrane

1. permeability barrier

2. protein anchor

3. energy conservation - site of generation and use of proton motive force

Is the membrane fixed? why or why not

not fixed, held together by hydrophilic and hydrophobic forces

What is the function of the nucleus?

It contains the cell's genetic material (DNA), site of ribosome synthesis, inside nucleus is chomatin stored in nucleoplasm

What is chromatin?

DNA wrapped around proteins inside the nucleus.

What are nuclear pores?

Channels through the nuclear envelope that allow substances to enter and leave the nucleus.

What is the nucleolus?

A region inside the nucleus where new ribosomes are assembled (synthesis of ribosomal RNA)

What are ribosomes made of, and function?

protein factory made of RNA and proteins.

What is the main function of mitochondria?

Aerobic respiration and extraction of energy from organic molecules (O2 used as electron acceptor)

What is the main function of chloroplasts?

Photosynthesis, using solar energy to produce organic molecules and O₂.

Which cells contain chloroplasts?

Plant cells.

What important feature do mitochondria and chloroplasts share?

Both contain inner membranes with enzymes involved in their respective energy-producing processes.

What additional feature of mitochondria and chloroplasts?

They contain their own DNA and replicate by binary fission, supporting the idea that they evolved from prokaryotic organisms.

what is the most extensive membrane in the eukaryotic cell

endoplasmic reticulum

What is the general function of the endoplasmic reticulum (ER)?

involved in protein modification and lipid synthesis.

What is the function of the rough ER?

studded with ribosomes that synthesize secreted proteins

What is the function of the smooth ER?

It is involved in synthesis of carbohydrates, lipids, and steroid hormones and in detoxification of medications and poisons.

What is the function of the Golgi apparatus?

It receives and processes materials from the ER and acts as the cell's final assembly and packaging unit. recieves, processes, and produced variety of vesicles

What is a vesicle?

A small membrane-bound package containing biological molecules.

What happens to many secreted proteins and lipids in the Golgi apparatus?

Shuttled from er to the golgi where they undergo further modification, such as the addition of carbohydrates, before being packaged.

uni/multicellular pro vs eu

pro - mostly uni vs eu - mostly mult

cell wall differences

pro - complex cell wall vs eu - simpler cell wall in yeast and plant cells (none in animal cells)

flagella differences

pro - made from single protein vs eu - made from complex microtubules

Ribosomes

translate RNA to proteins

What structures are found in both prokaryotic and eukaryotic cells?

Both have a cytoplasmic membrane, cytoplasm, genetic material stored as DNA, and ribosomes.

What is the key difference in the location of genetic material in prokaryotes versus eukaryotes?

Prokaryotic DNA is located in the nucleoid without a surrounding nuclear membrane; eukaryotic DNA is enclosed inside a nucleus.

What is an autotroph?

An organism that uses simple inorganic molecules plus an energy source to produce organic molecules.

What is a photoautotroph?

An autotroph that uses solar energy.

What is a chemolithotroph?

An organism that obtains energy through redox reactions involving inorganic compounds.

What is a heterotroph?

An organism that obtains energy from pre-existing organic molecules.

What is an obligate anaerobe?

An organism for which O₂ is toxic.

What is an obligate aerobe?

An organism that must use O₂.

What is a facultative anaerobe?

An organism that can grow either in the presence or absence of O₂.

Why are bacteria useful for biotechnology?

They grow rapidly, foreign DNA can be introduced relatively easily, and strains producing a desired product can be selected, making them useful for applications such as recombinant protein production.

What are recombinant proteins?

Proteins produced by introducing DNA encoding the desired protein into a host cell so that the cell produces the protein.

Why are fungi/yeast useful in biotechnology?

They can produce industrially useful products such as ethanol, organic acids, amino acids, polymers, enzymes, antibiotics, and recombinant proteins.

What is yeast?

A unicellular fungus.

Why are animal cells useful in biotechnology?

Their ER and Golgi provide complex cellular machinery that can modify proteins in ways required for many therapeutic products.

What are examples of products commonly made using animal cells?

Therapeutic proteins such as antibodies and cytokines, as well as vaccines.

What are CHO cells?

Chinese hamster ovary cells, a common animal cell type used to produce complex recombinant therapeutic proteins.

What are the major disadvantages of animal cells for biotechnology?

They grow slowly, are fragile, and are expensive to culture.

If you need to rapidly and cheaply produce a relatively simple recombinant protein, which cell type would generally be preferred?

Bacteria such as E. coli because they grow rapidly and are easy to genetically manipulate.

What is the general size hierarchy of biological systems?

Atoms < small molecules < macromolecules < organelles < prokaryotic cells < eukaryotic cells < tissues.