Chapter 1
What are the functions of muscle, nervous, epithelial, and connective tissues?
Muscle: contraction and force
Nervous: initiate, integrate, conduct
Epithelial: secretion, absorption, protection
Connective: connect, anchor, support body structures
What is the difference between cations and anions?
Cations: net positive charge
Anions: net negative charge
Where are the codon and anticodon during translation?
Codons are a sequence of 3 nucleotides in the mRNA. The anticodon is on the tRNA.
During translation, they bind together, and the anticodon of the tRNA codes for a specific amino acid.
The inside of a cell is relatively _____ compared to the outside of the cell.
Negative
What is phosphorylation?
Transferring a phosphate group from ATP to a protein to energize and activate or deactivate it.
What physical environment separates connective tissue cells?
What creates this environment?
Extracellular matrix (ECM);
Connective tissue cells make ECM
What are hydrolysis and dehydration synthesis?
Hydrolysis: breaks apart organic molecules
Dehydration synthesis: builds organic molecules
What happens to the primary mRNA transcript before it leaves the nucleus?
It is spliced by spliceosomes, which remove the introns. Then it officially becomes mRNA (where only exons are expressed).
What does moving against a concentration gradient mean?
To go against a concentration gradient is to start from an area with low concentration and move into an area with high concentration.
What is a kinase?
An enzyme that performs phosphorylation. Kinase will hydrolyze ATP, then kinase takes the phosphate to other proteins, and activates or deactivates them.
What is the difference between negative feedback, resetting of set points, and feedforward regulation?
Negative feedback: counteracts changes to physiological variables. Stops once the set point has been reached.
Resetting of set points: normal values for variables are set to a new value
Feedforward regulation: changes to regulated variables are anticipated and prepared for before they occur
What is glycogen and where is it stored?
Excess carbohydrate energy that is stored in skeletal muscles and the liver.
What is the net amount of ATP produces in glycolysis, Krebs cycle, and oxidative phosphorylation per molecule of glucose? In total?
Glycolysis: 2 ATP
Krebs Cycle: 2 ATP
Oxidative Phosphorylation: 32 ATP
Total: About 36 ATP
Why can't polar molecules readily diffuse across a membrane?
Polar molecules are hydrophilic, and the interior of the membrane is hydrophobic.
What activates cAMP dependent protein kinase?
cAMP!
What is the difference between hormones, neurotransmitters, paracrine substances, and autocrine substances?
Hormones travel via blood vessels and target cells in distant parts of the body.
Neurotransmitters target neurons or effectors that are close to the site of release.
Paracrine substances target their neighbors.
Autocrine substances target themselves.
What are the secondary conformations of proteins and how are they held together?
Alpha helix, beta plated sheet
They are held together by hydrogen bonds
How do Pyruvate and Acetyl CoA relate to glycolysis and the Krebs cycle?
Glycolysis produces 2 Pyruvate. The Pyruvate is then converted into 2 Acetyl CoA. Acetyl CoA is the input for the Krebs Cycle.
What do we lose AND gain from the Sodium / Potassium pump?
Lose 3 Na+
Gain 2 K+
What causes the alpha subunit of G-Protein to dissociate from the beta and gamma subunits and gain affinity for GTP?
The binding of the first messenger.
Describe what happens during the reflex arc when you walk outside into the freezing cold.
You walk into the cold (stimulus), and your thermoreceptors detect this. They send the information that you are cold via the afferent pathway towards the integrating venter. The integrating center decides what should be done, and sends the comand vie the efferent pathway to the muscles (effectors). The muscles contract and relax repeatedly, which we know as shivering (response). This releases energy as heat, which warms you up again.
Name all of the building blocks and functions of the organic molecules.
Carbohydrates: Monosaccharides; short term energy storage
Proteins: Amino Acids; many functions
Lipids: Fatty Acids; long term energy storage
Nucleic Acids: Nucleotides; storage of genetic information
Describe the role of NADH, FADH2, and ATP synthase during the electron transport chain and oxidative phosphorylation.
NADH and FADH2 give up their electrons (bound to H+) in the electron transport chain. These electrons are pumped against their concentration gradient into the intermembrane space of the mitochondria by cytochromes (proteins). The electrochemical gradient favors the movement of the protons (H+) back into the matrix. The only way for this to occur is to pass through ATP synthase. As the protons pass through ATP synthase, it generates the energy needed to convert ADP into ATP.
How is ATP used in the Sodium Potassium pump, and how does phosphorylation play a role?
ATP is used to give a phosphate to the ATPase pump, allowing for 3 Na+ to attach to ATPase. On the ATPase pump, there is a phosphorylation site that uses a phosphate from the original ATP. This phosphorylation allows for the pump to release the 3 Na+ into the ECM. The phosphate stays bound until 2 K+ bind to the ATPase pump. When the phosphate is released, the 2 K+ are brought into the intracellular fluid.
What is the cell signaling pathway that causes the cytosolic concentration of Ca2+ to be increased?
G-Protein Coupled Receptors: DAG and IP3. Specifically, IP3 (second messenger) binds to receptors on the ER. These receptors are on ligand-gated Ca2+ channels. When the channels open, Ca2+ diffuses out into the cytosol.
Note: Ca2+ can act as a second messenger for other physiological processes such as muscle contraction.