Levels of Biological Organization and Domains of Life

Flashcards created from the lecture notes covering elemental composition, levels of biological organization, cell structures, domains, and kingdoms of life.

What is an atom?

An atom is the smallest unit of an element.

What percentage of living organisms do CHON elements make up combined?

CHON makes up 96% out of every other element.

What are the exact percentage compositions of Carbon, Hydrogen, Oxygen, and Nitrogen in living organisms?

Carbon makes up 18.5%, Hydrogen makes up 9.5%, Oxygen makes up 65%, and Nitrogen makes up 3.3%.

What are the percentage compositions of Phosphorous, Sulphur, Sodium, Magnesium, Chlorine, Potassium, and Calcium in living organisms?

Phosphorous is 1%, Sulphur is 0.3%, Calcium is 1.5%, Potassium is 0.4%, Sodium is 0.2%, Chlorine is 0.2%, and Magnesium is 0.1%.

What is the complete sequence of biological organization from simplest to most complex?

molecule → organelle → cell → tissue → organ → organ system → organism → population → community → ecosystem → biosphere.

How is the Molecular Level defined, and what are some examples?

Chemical structures made of two or more atoms bonded together representing the smallest units of matter that can carry out specific chemical functions in living systems, such as DNA, proteins, and carbohydrates.

How is the Cellular Level defined, and what vital processes can it perform?

The smallest independently functioning unit of life where organelles first appear and group together to carry out specific functions capable of performing processes such as metabolism, growth, and reproduction.

What is the Tissue Level in biological organization?

Groups of similar cells that work together to perform a specific function, such as muscle or nervous tissue.

How is the Organ Level defined?

Structures normally composed of several tissue types that form a functional unit, such as the heart, liver, or lungs.

What defines the Organ System Level?

Combinations of organs that perform complex functions, such as the circulatory system.

What defines the Multicellular Organism Level?

Individual living entities composed of many cells, such as a dog, tree, or human.

What is the Population Level in biological organization?

Groups of the same species, such as a herd of elephants.

How is the Community Level defined?

Different populations interacting in a specific area, including plants, animals, fungi, and bacteria, such as in a forest.

What defines the Ecosystem Level, and what are its biotic and abiotic factors?

Interactions between organisms and their environment, including biotic factors (plants and animals) and abiotic factors (soil, water, air, climate), with coral reefs as an example.

What is the Biosphere Level?

The global sum of all ecosystems, representing life on Earth, including deserts, forests, wetlands, etc.

What are the primary differences between prokaryotic cells and eukaryotic cells?

Prokaryotic cells are simple, small, have no nucleus, and have few organelles (e.g., bacteria and archaea). Eukaryotic cells are larger and more complex, have a nucleus and many organelles, and make up all other types of organisms (e.g., mushrooms and plants).

What are the 3 broad categories or domains of life?

Domain Bacteria, Domain Archaea, and Domain Eukarya.

What are the characteristics of Domain Bacteria?

Contains only bacteria with prokaryotic cells that may be pathogenic or beneficial (good or bad), such as E Coli.

What are the characteristics of Domain Archaea, and what example is given?

Contains only archaea with prokaryotic cells that live in extreme environments; an example is Sulfolobus, which gets its energy from iron and lives in a volcanic vent.

What kingdoms are included within Domain Eukarya?

Domain Eukarya contains Kingdom Protista, Kingdom Plantae, Kingdom Animalia, and Kingdom Fungi.

How is Kingdom Protista defined?

Mostly single-celled pond water organisms, such as green algae and seaweed.

How is Kingdom Fungi defined?

Eukaryotic organisms that absorb nutrients from organic matter and reproduce via spores, such as mushrooms.

How is Kingdom Plantae defined?

Multicellular, eukaryotic, autotrophic organisms that perform photosynthesis, such as trees.

How is Kingdom Animalia defined?

Multicellular, eukaryotic, heterotrophic organisms, such as lions.