A2.1 Origin of cells Flashcards
How old is planet Earth
It is 4.5 billion years old
How was Earth believed to be formed?
It was believed that swirling masses of tiny molecules collided with one another and formed larger masses. which in turn had more gravity which attracted other masses eventually forming earth.
What molecule was not present?
free oxygen
What gases were in higher concentrations that allowed ultraviolet light through
Carbon dioxide and methane
What were the compounds in the atmosphere?
Methane, ammonia, carbon dioxide, water vapour, hydrogen sulphide, hydrogen, and nitrogen.
What are the functions of organisms?
Metabolism, Growth, Reproduction, Response, Homeostasis, Nutrition, and Excretion.
What is metabolism?
All chemical reaction that occur inside the organism. Converting one form of energy into another.
What is growth?
Cells accumulating mass. May be limited but always present
What is reproduction?
Involving hereditary molecules that can be passed off to offspring
What is response?
Responding to stimuli in its environment which allows the cell to adapt.
What Is homeostasis
The maintenance of a constant internal environment
What is nutrition?
The process of making sure our body’s cells receive the nutrients they need so they can perform all of their major functions
What is excretion?
Enables chemical compounds that an organism cannot use or that may be toxic or harmful to the cell.
List the components of cell theory.
- All organisms are composed of one or more cells
- Cells are the smallest unit of life
- All cells come from pre existing cells
Who first discovered cells in 1665?
Robert Hooke after looking through a self built microscope.
What did Antonie van Leeuwenhoek discover?
He observed the first living cells and referred to the as “Animalcules”
Are viruses considered living organisms? Why or why not?
They are not considered living organisms because they can not carry out functions of life by themselves. They have to rely on host cells in order to live and reproduce.
What was the chicken broth experiment?
In the 1880’s Louis Pasteur sterilized chicken broth showing that living organisms were not able to spontaneously reappear. Only after exposure to pre existing cells was life able to be formed again.
What did Botanist Matthias Schleiden state?
Plants are made of “Independent, separate beings” called cells.
What is the process for cells to evolve?
- The synthesis of small carbon compounds form abiotic molecules
- Small organic molecules going to form large chains molecules (Polymers)
- Polymers becoming contained by membranes, creating a protective homeostasis environment around the polymers depurating from their suroundings.
- The development of self replicating molecules so that inheritance and control can occur
What helps the process of cell evolution
Enzyme like components
What are enzymes?
- Can help to from polymers if enzymes are present.
- Biological catalysts that acerbate chemical reactions.
- Carbon compounds which means they always contain carbon and hydrogen and other molecules
What are inorganic compounds?
Do not usually contain carbon ( with the exception of CO2)
What are Organic compounds?
Contain carbon and are refers to carbon compounds and are quit complex. They are the key to the element of life.
What is the Miller-Urey experiment?
It was intended to simulate the condones thought to be during Early Earth, to determine if these gasses could interact to produce the first stage of evolution in life.
Explain the Miller-Urey experiment?
- The apparatus is initially charged with simple inorganic compounds CH4, NH3, and H2
- Heat is used to produce water vapour which rises to the container that contains the simple inorganic compounds.
- 2 electrons in a chamber produce 7500 volts at 30 amps of electricity, simulating lightning on early earth.
-Cold water flows into the condenser to allow the condensation of gaseous compounds from the chamber. - A sample from the device is collected for chemical analysis.
What was concluded from the Miller-Urey experiment?
-Several organic molecules known to exist in organisms were identified
- The molecules included long chains of hydrogen and carbon called hydrocarbons.
- The building blocks of protein called amino acids were found.
-The experiment suggested to scientists that life originated in a primordial soup.
