Question

which type of substances serves as a catalyst for reactions that break large food molecules into smaller useful molecules?
a. enzymes
b. vitamins
c. lipids
d. nucleotides
this is an mrna codon
chart. which amino acid
chain is formed from the
sequence tac tta cgc
gag?
a. tyrosine – histidine –
glycine – aspartic
acid
b. tyrosine – leucine –
arginine – glutamic
acid
c. methionine –
asparagine –
glycine– isoleucine
d. methionine – asparagine – alanine – leucine
natural selection cannot occur without
a. competition for unlimited resources.
b. gradual warming of earth.
c. genetic variation in species.
d. asexual reproduction in species.
which of the following best explains why different proteins contain a differen
number and a different sequence of amino acids?
a. proteins are produced by different ribosomes.
b. proteins are coded by genes with different nucleotide sequences.
c. proteins are different because each codon codes for more than one
amino acid.
d. proteins combine in different ways based on the cellular need.
response: a female lizard develops a mutation in a gene. she has an offspri
itary trait. based on these events, give two pieces of information about the ne

Explanation:

1. Question 1: Enzymes are biological catalysts that speed up the hydrolysis of large food macromolecules into smaller absorbable molecules, while vitamins are cofactors, lipids are energy storage molecules, and nucleotides are building blocks of nucleic acids.
2. Question 2: First convert the DNA sequence TAC TTA CGC GAG to mRNA (AUG AAU GCU CUC). AUG codes for Methionine, AAU codes for Asparagine, GCU codes for Alanine, CUC codes for Leucine.
3. Question3: Natural selection requires genetic variation in a population to select for favorable traits; unlimited resources remove selection pressure, warming is not required, and asexual reproduction limits variation.
4. Question4: Genes hold the nucleotide sequence that dictates the amino acid sequence and length of the resulting protein via the genetic code. Ribosomes only assemble proteins, codons are unambiguous, and cellular need does not define core protein structure.

Answer:

1. a. enzymes
2. d. Methionine - Asparagine - Alanine - Leucine
3. c. genetic variation in species.
4. b. Proteins are coded by genes with different nucleotide sequences.