The Nature of Life on Earth Flashcards
What are the 5 Attributes to Life?
Growth:
- changes in size (like a child growing
Energy Utilization:
- eats food
- converts food into energy
Response to the environment:
- Avoid getting killed
- go where they are more likely to survive
Evolutionary Adaption (Evolution):
- adapting and changing to environment to increase chances of surviving in their environment.
Who is Charles Darwin?
Darwin proposed that species evolve over time through a process called natural selection. This means that individuals with traits better suited to their environments are more likely to survive and reproduce, passing those traits on to future generations.
Why is the Order ( organized structure and functioning of living organisms) an attribute to Life?
Cells, tissues, and organs all work in orderly manner, allowing organisms to maintain temperature and perform essential functions like respiration, digestion, and movement.
Why is Reproduction an Attribute to Life?
Reproduction is essential for passing genetic information from one generation to the next. Without it, a species would not be able to sustain its population over time, leading to extinction.
Reproduction also occurs at the cellular level. Cells divide to replace damaged or worn-out cells, allowing organisms to maintain their health and functionality over time.
Why is growth important to the attribute of life?
Growth allows organisms to develop from a simple, often microscopic form (such as a single cell) into a fully functional adult capable of survival and reproduction.
Why is Energy Utilization an attribute life?
Energy utilization is essential because it drives every activity and process that sustains life, from the molecular level to the organism as a whole. Without energy, life wouldn’t be able to function or survive. For example, food.
Why is Life’s Responses an important attribute to life?
Life’s responses, or responsiveness, are crucial because they enable organisms to detect and react to changes in their environment, ensuring survival and well-being. For example, moving to a different biome where life is more suited for them
Why is evolution important to Life’s attribute?
Evolution is an essential attribute of life because it explains how organisms change over time to adapt to their environments, ensuring the survival and development of species.
What is the Natural Selection? (Hint: Charles Darwin)
Natural selection is the process through which organisms better adapted to their environment are more likely to survive and reproduce. Here’s a concise summary:
Individuals in a population have different traits due to genetic differences.
Species often produce more offspring than can survive due to limited resources.
Individuals compete for resources like food and shelter.
Those with advantageous traits are more likely to survive and reproduce, passing those traits to the next generation.
Over time, this process leads to the adaptation of populations to their environments and contributes to the evolution of species.
What is the tree of life?
The Tree of Life is a metaphorical representation that illustrates the evolutionary relationships among various species on Earth. It depicts how different organisms are connected through common ancestry, reflecting the process of evolution over billions of years.
What is bacteria, archaea and eukarya?
Bacteria, Archaea, and Eukarya are the three main domains of life, each representing a distinct group of organisms with unique characteristics.
Do prokaryotic cells have a membrane-bound nucleus?
No, prokaryotic cells, such as bacteria, do not have a membrane-bound nucleus. Their DNA is located in a region called the nucleoid, which is not enclosed by a membrane.
Do eukaryotic cells have a membrane-bound nucleus?
Yes, eukaryotic cells have a membrane-bound nucleus that contains their genetic material (DNA) and regulates gene expression. This is a defining feature of eukaryotes.
What is a cell?
A cell is the basic structural and functional unit of all living organisms. It is the smallest unit of life capable of carrying out processes like metabolism, growth, and reproduction. Cells are classified into two types: prokaryotic (without a nucleus) and eukaryotic (with a nucleus).
What are the primary chemical elements found in a cell?
The primary chemical elements in a cell include:
Carbon (C): Backbone of organic molecules.
Hydrogen (H): Present in water and organic compounds.
Oxygen (O): Essential for cellular respiration and in organic molecules.
Nitrogen (N): Key component of amino acids and nucleotides.
Phosphorus (P): Found in nucleic acids and ATP for energy transfer.
Sulfur (S): Component of some amino acids and vitamins.
What is a covalent bonds?
A bond formed when two atoms share one or more pairs of electrons to achieve stability.
Key Points:
Occurs mostly between nonmetals.
Creates molecules with specific shapes and strong internal bonds.
Example: H₂O (water), where hydrogen and oxygen share electrons.
What are ionic bonds?
A bond formed when one atom donates an electron to another, resulting in oppositely charged ions that attract each other.
Key Points:
Typically forms between metals and nonmetals.
Creates compounds with a lattice structure and high melting points.
Example: NaCl (table salt), where sodium donates an electron to chlorine.
What is hydrogen bond?
A weak bond between a hydrogen atom covalently bonded to an electronegative atom (like oxygen or nitrogen) and another electronegative atom.
hydrogen bonds are weaker attractions between molecules or different parts of a molecule.
Key Points:
Found in water and DNA, holding molecules together.
What are molecules?
The smallest unit of a substance made up of two or more atoms bonded together.
Key Points:
Can be made of the same or different atoms.
Held together by bonds, usually covalent bonds.
Why is silicon life based?
A hypothetical form of life that would use silicon instead of carbon as its basic building block.
Key Points:
Why Silicon? Silicon is similar to carbon and can form complex molecules.
Challenges: Silicon bonds are generally less stable, making it harder for complex life to develop.
Hypothesis: Mostly found in science fiction; no silicon-based life has been observed.
Fun Fact: Carbon is preferred in life on Earth because it forms stable, flexible molecules essential for life functions.
Why Carbon is Life’s Building Block
Carbon is the main element in living organisms because of its unique bonding abilities, allowing complex and stable molecules essential for life.
Key Points:
Versatile Bonds: Carbon can form four strong, stable bonds with other atoms, creating complex structures.
Diversity: It easily forms chains, rings, and large, diverse molecules.
Stability and Flexibility: Carbon-based molecules are both stable and flexible, crucial for biochemical reactions.
What is the water molecule?
A polar molecule made of two hydrogen atoms and one oxygen atom, essential for life.
Key Points:
Polarity: Has slightly negative (oxygen) and slightly positive (hydrogen) ends, allowing it to form hydrogen bonds.
Properties: Hydrogen bonds give water a high boiling and freezing point, high surface tension, and the ability to store heat.
Ice: Water molecules in ice are arranged in a structure with lower density than liquid water, so ice floats.
Heat Storage: Water can absorb a lot of heat without changing temperature quickly, making it important for regulating temperature.
What are the molecular components of a cell that allows to function?
Proteins
Made of amino acids
Function: Catalyze reactions, provide structure, and enable communication
Nucleic Acids
Types: DNA and RNA
Function: Store and transmit genetic information
Lipids
Includes phospholipids and cholesterol
Function: Form cell membranes and store energy
Carbohydrates
Types: Sugars and starches
Function: Provide energy, support structure, and assist in cell recognition
What are enzymes?
Definition: Enzymes are proteins that help speed up chemical reactions in the body.
Function: They act like tools, making reactions happen faster and easier.
Specificity: Each enzyme works on a specific substrate (the molecule it helps change).
Role: Enzymes lower the energy needed for reactions, allowing processes like digestion and metabolism to occur efficiently.
