Biology Regions Exam Studies

What is homeostasis?

What happens if homeostasis fails?

The ability of an organism to maintain a stable balanced environment.

Failure results in sickness or death.

What is metabolism?

The sum of all the chemical reactions that occur within the cells of an organism.

What skeleton structures do organic molecules contain?

Mainly carbon with hydrogen and oxygen.

What is the organization of living things?

Cells —> Tissues —> Organs —> Organ Systems —> Organism

What are organelles?

The small parts that make up a cell, all have at least one specific function.

What are vacuoles?

Organelles that store waste and water. They are large in plant cells, small in animal cells.

What is a ribosome?

Very small organelles where proteins are made in the cell (protein synthesis).

What are mitochondria?

The organelles where energy is made. Site of cellular respiration in both plant and animal cells.

What are chloroplasts?

Organelle where the process of photosynthesis occurs. Only found in plant cells.

What is the formula for photosynthesis?

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂ / sun’s energy + carbon dioxide + water —> glucose + water +oxygen

What is a nucleus?

An organelle that functions as the control center of the cell and contains DNA.

What is cytoplasm?

The liquid media that fills the cell.

What is the cell membrane?

The outside layer of the cell that separates the contents of the cell from the outside environment. It controls the transport of materials into and out of the cell (selective permeability).

What is cellular communication?

How cells recognize and respond to chemical signals by using receptor molecules.

What is passive transport/diffusion?

The movement of molecules from areas of high concentration to low concentration (NO ENERGY USED).

What is active transport?

When molecules move from low concentration to a high concentration (USES ENERGY in the form of ATP).

Where are the chemicals that allow cellular communication to happen produced?

The endocrine glands (hormones) and nerve cells.

What is cellular respiration?

The process used by all organisms to produce energy by using oxygen to burn sugar in order to release energy in the form of ATP. Occurs in the mitochondria.

What is digestion?

Breaking large molecules down into smaller molecules.

1. What do proteins break down into during digestion?

2. What do carbohydrates and starches break down into during digestion?

3. What are fats (lipids) broken down into during digestion?

1. Amino acids

2. Simple sugars

3. Fatty acids & glycerol

What is transport?

The movement of materials inside the cell as well as the movement between parts of a multicellular organism.

What is excretion?

The removal of all waste produced by the cells of the body.

What is synthesis?

The making or building of large molecules from smaller ones.

What is photosynthesis?

The process of storing energy from the sun in the chemical bonds of glucose (sugar). Only occurs in plants.

What the chemical formula for cellular respiration?

C₆H₁₂O₆ + 6O₂ --> 6CO₂ + 6H₂O + Chemical Energy (in ATP)

glucose + oxygen —> carbon dioxide + water + energy (ATP)

What are enzymes?

Special proteins that affect the rate of chemical reactions. They are catalysts used in digestion and synthesis.

What are enzyme reaction rates affected by?

1. Shape

2. Temperature

3. PH

What is dynamic equilibrium?

A steady state balance where the forward and reverse reactions occur at the exact same rate.

What is homeostasis?

The process by which an organism regulates it’s internal environment to maintain stability and function (regardless of external changes).

What is negative feedback?

The process that controls hormone levels to maintain homeostasis.

What are antigens?

The receptor proteins on the membrane of pathogens (germs).

What are antibodies?

Special proteins produced by white blood cells that are used to fight of diseases.

What is immunity?

Our bodies ability to fight disease based on previous contact with the disease.

What are vaccinations?

Weakened or dead virus that triggers our white blood cells to produce antibodies to fight a specific pathogen.

What are diseases caused by?

Pathogens (virus, bacterium, and fungus).

1. What is cell division?

2. What are the two types?

1. When a single parent cell divides to produce two or more daughter cells.

2. Mitosis and meiosis

What is mitosis?

A form of cell division used for growth, repair and asexual reproduction.

What is meiosis?

A form of cell division that occurs only in the male and female gonads and solely produces gametes.

What are gonads?

The reproductive glands (ovaries and testis).

What are gametes?

Reproductive cells that unite in fertilization to form a zygote.

What is a zygote?

A fertilized egg.

What is fertilization?

When a male and female gamete unite.

1. How many chromosomes does a gamete have?

2. How many chromosomes does a zygote have?

1. 23

2. 46

What is differentiation?

The process that transforms developing cells into specialized cells with different structures and functions.

What is cancer caused by?

When certain genetic mutations in a cell results in uncontrolled cell division.

What is heredity?

The passing of genetic information from one generation to the next through reproduction.

What is asexual reproduction?

When one parent cell produces a clone of themself. Little genetic variation.

What is sexual reproduction?

When two parent cells produce a new cell by combining their genetic factors. Much genetic variation.

What is DNA?

A double stranded helix polymer of nucleotides that contains the genetic code of the individual.

What is a nucleotide?

The basic unit of DNA which is made of a phosphate, a sugar and a base.

1. What are DNA bases?

2. How are they paired?

1. A, T, G, C

2. A is paired with T, G is paired with C

What is RNA?

A single stranded polymer that is produced by DNA.

What are the three types of RNA?

1. Messanger RNA

2. Transfer RNA

3. Ribosomal RNA

What are the bases for RNA?

A, U, G, C

How does protein synthesis work?

1. DNA is stuck in the nucleus, so it sends a messenger single- stranded mRNA to the ribosome

2. the ribosme reads the message and directs the tRNA to bring it amino acids

3. the ribosome assembles the amino acids together in the correct order to make a protein

What is mutation?

Any alteration of the DNA sequence which changes the normal message carried by the gene.

What is substitution?

A mutation where one DNA base is put in the place of another.

What is deletion?

A mutation where one DNA base is left out.

What is addition?

A mutation where one extra DNA base is added.

What is inversion?

A mutation where the DNA bases are switched.

What is gene expression?

The process by which the genetic instructions in your DNA are converted into a functional product.

What can affect gene expression?

An organism’s environment.

What is genetic engineering?

A technology used to alter the genetic instructions of organisms.

What is gene splicing?

Cutting DNA and placing it into another organism.

What is a restriction enzyme?

An enzyme that cuts DNA in specific places.

What is selective breeding?

The process of picking parents with favorable traits to produce those traits in the offspring.

What is a species?

A group of closely related organisms that share certain characteristics and can produce offspring capable of reproduction.