Which of these is the portion of the heartbeat that involves contraction of the heart?
A) cardiac cycle
B) pacemaker
C) diastole
D) systole
D
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During interaction between genes and environment, the phenotype ____
a. changes the genotype b. is expressed as discontinuous variation c. is variable and undergoes continuous change throughout the life of the organism d. can be quantitatively subdivided into genotypic and environmental components e. cannot vary
Which field of ecology analyzes how large-scale ecological factors influence local populations and communities?
a. conservation ecology b. mixed-use conservation c. alpha-diversity
d. landscape ecology e. community ecology
Forests serve to
a. hold water. b. control soil erosion. c. control flooding. d. control sediment buildup in lakes, rivers and reservoirs. e. all of these.
What is the nucleotide sequence on a section of DNA where transcription begins?
A) polymerase B) palindrome C) promoter D) codon