Cell Biology and Classification

Flashcards from lecture notes on Nucleic Acids, Cell Organelles, Cell Types, Cell Theory, Cell Transport, Homeostasis, Biochemical Reactions, Cell Division, Classification

What is the main function of nucleic acids?

To direct the instruction of proteins and carry genetic information.

Name the two types of nucleic acids.

DNA (deoxyribonucleic acid) and RNA (ribonucleic acid)

What is the function of chloroplasts?

Capture solar energy for photosynthesis.

What is the function of the Golgi Body?

Package and distribute products.

What is the function of lysosomes?

Digests excess products and food particles.

What is the function of mitochondria?

Transform energy through respiration.

What cellular component contains DNA and controls cellular activities?

Nucleus

What is the function of ribosomes?

Produce proteins.

What is the function of vacuoles?

Store substances.

What is the function of the cell (plasma) membrane?

Protects and encloses the cell; controls transport; maintains homeostasis.

What is the function of the cell wall?

Protects and encloses the cells in plant cells and some bacteria.

What is a unicellular organism?

An organism that exists as a singular, independent cell.

What is a multicellular organism?

An organism that exists as specialized groups of cells; cells are organized into tissues that perform the same function; tissues form organs and organs make up an organ system.

What is a prokaryotic cell?

A cell that has nuclear material in the center of the cell, but is not enclosed by a nuclear membrane; no membrane-bound organelles; found in bacteria and blue-green bacteria.

What is a eukaryotic cell?

A cell that contains a clearly defined nucleus enclosed by a nuclear membrane and membrane-bound organelles; found in plants, animals, fungi and protists.

What are the three parts of the cell theory?

The cell is the basic unit of life; all organisms are composed of cells; all cells come from pre-existing cells.

What is passive transport?

Movement of substances across the plasma membrane without the use of the cell's energy (with the concentration gradient).

What is diffusion?

Movement of substances across the plasma membrane from an area of high concentration to an area of low concentration.

What is osmosis?

Diffusion of water across the plasma membrane from areas of high concentration to areas of lower concentration.

What is facilitated transport?

A carrier molecule embedded in the plasma membrane transports a substance across the plasma membrane following the high-to-low concentration gradient.

What is active transport?

Movement of substances across the plasma membrane that requires the use of the cell's energy and carrier molecules; substances are moving from an area of low concentration to an area of higher concentration (against the concentration gradient).

What is endocytosis?

Large particles are brought into the cell.

What is exocytosis?

Large particles leave the cell.

What is homeostasis?

Internal equilibrium; the plasma membrane regulates what enters and leaves the cell; a selectively permeable membrane only allows certain substances to pass through.

What happens to a cell in a hypotonic solution?

Water moves in; cell bursts.

What happens to a cell in a hypertonic solution?

Water moves out; cell shrivels.

What happens to a cell in an isotonic solution?

No net movement; cell maintains equilibrium.

What is the ultimate source of energy for all living things?

The Sun (in Chemosynthesis, organisms use sulfur or nitrogen as the main energy source)

What is ATP?

A molecule that stores and releases the energy in its bonds when the cell needs it.

What two types of fermentation are there?

Lactic Acid Fermentation (muscle cells) and Alcoholic Fermentation (plant cells)

What is cellular respiration?

Food molecules are converted to energy; there are three stages to cellular respiration; the first stage is called glycolysis and is anaerobic (no oxygen is required); the next two stages are called the citric acid cycle and the electron transport chain and are aerobic (oxygen is required).

What is photosynthesis?

Plant cells capture energy from the Sun and convert it into food (carbohydrates); plant cells then convert the carbohydrates into energy during cellular respiration; the ultimate source of energy for all living things is the Sun (in Chemosynthesis, organisms use sulfur or nitrogen as the main energy source)

What are the three types of cell division?

Binary fission (bacteria and fungi), mitosis, and meiosis

What is asexual reproduction?

A single parent produces one or more identical offspring by dividing into two cells - mitosis (protists, arthropods, bacteria by binary fission, fungi, plants); produces large numbers of offspring. Offspring are clones of parents (genetically identical). Common in unicellular organisms, good for stable environments.

What is sexual reproduction?

Pattern of reproduction that involves the production and fusion of haploid sex cells; haploid sperm from father fertilizes haploid egg from mother to make a diploid zygote that develops into a multicellular organism through mitosis. Results in genetic variation (diversity). Common in multicellular organisms (external or internal fertilization); good for changing environments.

What are the phases of mitosis?

Prophase, metaphase, anaphase, telophase

What is taxonomy?

Branch of biology that studies grouping and naming of organisms.

What is binomial nomenclature?

A system of naming organisms with two names, a genus and a species. Genus is always capitalized, and both names should be underlined or italicized.

What are the six kingdoms?

Archaebacteria, Eubacteria, Protista, Fungi, Plantae, and Animalia

What is a dichotomous key?

A tool used to identify organisms by using pairs of contrasting characteristics.

What is the order of levels of classification?

Kingdom, Phylum, Class, Order, Family, Genus, Species