Final Biology Exam Spring

Independent variable

manipulated (stands alone)

dependent variable

responding

hypothesis

theory based on limited evidence

Homeostasis

 state of steady internal, physical, chemical, and social conditions maintained by living systems

Equilibrium

When the concentration of molecules on either side of the membrane are equal

Feedback loop

Response to a stimulus to enhance or stop it

Stimulus

Outside influence on an organism or something that can trigger physical or behavioral change

response

physiological mechanism to an outside stimulus

positive feedback

feedback loop that enhances the stimulus

negative feedback

feedback loops that stops the stimulus

levels of organization

cell—>tissue—>organ—>organ system—>organism

DNA replication

process of DNA being copied (occurs during synthesis)

transcription

DNA—>RNA

translation

RNA—>protein

Gene expression

Using a gene to make a protein

cancer/tumor

cells uncontrollably dividing

P53

Protein that can inhibit CDK (Cyclin-dependent kinases) activity in G1 or G2 (plays a key role in controlling cell division and cell death)

mutation

Change in sequences of bases in DNA

gene

Section of DNA that codes for protein

Allele

What the gene actually says (different variations/genetic sequence)

DNA/Cell Damage

change in DNA base pairing that can cause damage to protein structure and functions. Cell cycle checkpoints avoid such damage

RNA

Single stranded, contains, ribose, uracil instead of thymine

Protein

An organic compound made up of small molecules (amino acids)

Cell cycle

Repeating series of event that includes growth, DNA synthesis, and cell division (G1→synthesis→G2→mitosis)

Gap phase

Cell growth and normal functions

synthesis phase

DNA is copied

Mitosis

Chromosomes divide (PMAT)

interphase

G1, synthesis, G2

Meiosis

A process that produces haploid gametes

checkpoint/cell cycle regulators

Protein signal the cell to either start or delay the next phase of the cycle

Apoptosis

the death of cells which occurs as a normal and controlled part of an organism's growth or development.

Genetic variation

The variation is due to independent assortment and crossing over during meiosis and random union of gametes during fertilization.

Crossing over

Exchange of genetic materials between non-sister chromatids or homologous chromosomes

Reduction division

Cell division that reduces the number of chromosomes in the cell

Fitness

The ability to survive and reproduce

adaption

an inherited characteristic that increases organism fitness

Natural selection

The process by which random evolutionary changes are selected for/by nature in a consistent, orderly, non-random way

evolution

Gradual change in species overtime

Phenotype/trait

Actual appearance resulting from the expression from the genes

artificial selection

Process by humans change a species by breeding it for certain traits

Genetic diversity

the range of different inherited traits within a species

conditions for evolution

When selective pressure push for natural selection among membrane of a species

Selective pressure

Populations of a species experience new environmental conditions in which they must survive (new habitat)

isolation

Populations of a species must be reproductively isolated from each other in order to evolve into separate species

variation

Genetic variation is the difference in DNA among individuals or populations

Population

group of organisms living in the same geographical area at the same time