Midterm 1 Flashcards
Chemical reactions that occur in the human body proceed quickly due to the activity of specialized….
proteins
Which of the following is an example of a membranous organelle?
A) lysosome, B) glycosome, C) centriole, D) ribosome, E) cytoskeleton
A. lysosome
The beta cells of the pancreas produce insulin, a protein-based hormone. Which of the following organelles would be found at higher levels in the beta cells?
A) motochondria, B) ribosomes, C) mocrovilli, D) lysosomes, E) smooth endoplasmic reticulum
B. ribosomes
If the adrenal cortex produces lipid-based hormones such as aldosterone, which organelle would be more abundant in cells of the adrenal cortex than in the adrenal medulla?
A) golgi apparatus, B) mitochondria, C) ribosome, D) rough endoplasmic reticulum, E) smooth endoplasmic reticulum
E. smooth endoplasmic reticulum
What is the aerobic metabolism of glucose look like?
C6H12O6 + 6O2 –>6CO2 + 6H2O + 30ATP
In the aerobic metabolism of glucose, electrons that were once part of the glucose become part of a molecule of…
water H2O
What proteins extend all the way across the plasma membrane?
transmembrane
Many enzymes can undergo a process called phosphorylation. This allows them to be…
A) produced, B) temporarily activated or inactivated, C) permanently activated or inactivated, D) exported from a cell, E) broken down to produce ATP
B. temporarily activated or inactivated
List the 4 bases found in DNA and indicate which pair with which.
Adenine, Thymine, Guanine, and Cytosine
Adenine pairs with Thymine
Guanine pairs with Cytosine
List the 4 bases in RNA
Adenine, Guanine, Cytosine and Uracil
What is transcription?
The first step of gene expression, in which a particular segment of DNA is copied into RNA (mRNA) by the enzyme RNA polymerase.
Since Thymine is not a base of RNA, what does adenine copy into in transcription?
Uracil
Transcription of the DNA sequence ATC yields what?
UAG
Adenine - Uracil (not thymine)
Thymine - Adenine
Cytosine - Guanine
What is translation?
the process of translating the sequence of a messenger RNA (mRNA) molecule to a sequence of amino acids during protein synthesis. The genetic code describes the relationship between the sequence of base pairs in a gene and the corresponding amino acid sequence that it encodes.
What is the translation starting point?
starting codon: AUG
What is the translation end point?
stop codon: UAA, VAB, UGA
For each NADH molecule that contributes to the electron transport system, the yield of ATP molecules is about what?
2.5
Identify two high energy electron carriers used in metabolism`.
NAD & FADH
NAD -> (+e-) -> NADH
FADH -> (+e-) -> FADH2
ATP synthase transfers the (potential/kinetic) energy of the H+ ions to the high-energy phosphate bond of (NADH/ATP).
- kinetic
2. ATP
There are 2 basic types of reactions in cells. By definition those that release energy are called what? Those that require the input of energy are called what?
exergonic reaction - releases energy
endergonic reaction - require the input of energy
Oxidative phosphorylation occurs where? An end product of it is what?
Occurs in the mitochondria due to the electron transport system;
End product - ATP
Generally speaking, a specific enzyme will be able to catalyze:
A) a single type of reaction, B) a diversity of chemical reactions
A) a single type of reaction
A ribosome will not begin synthesizing a protein (or polypeptide) until it “reads” the codon…
AUG
Define the term catabolism as it applies to metabolism.
Reactions that release energy through the breakdown of large biomolecules.
Define the term anabolism as it applies to metabolism.
Energy-utilizing reactions that result in the synthesis of large biomolecules.
When an ATP molecule is “used” to power a chemical reaction it is converted into: (list the products)
ATP —> ADP + Pi + energy