63 terms

Cell Physiology


Terms in this set (...)

Name one of the ways the body is able to maintain homeostasis?
Through feedback. Negative feedback is most common form.
The "effect" influences the "cause". ie. thermostat.
Name a homeostatic mechanism of the body.
Communication from different organs to different parts of the body to stay in homeostasis is endocrine.
Give and example of Hierarchical communication in regards to homeostasis?
Endocrine system. It triggers the nervous system to keep the body in homeostasis. Hypothalamus, pituitary, any other organ the pituitary helps control is a major homeostatic mechanism in the body.
What is adaptation in regards to homeostasis?
the steady-state is changed to accommodate a new situation. ie - altitude (create new red blood cells)
Name three ways the body is able to maintain homeostasis?
Feedback, Hierarchical communication, Adaptation
Why cellular physiology?
The cell is the smallest unit capable of carrying out the processes associated with life.
Name 7 Classical Properties of Living Organisms.
Reproduction, Nutrition, Respiration, Excretion, Irritability/respond, Movement Growth. (all properties of a cell)
How does a cell fulfill the 7 criteria of Living Organisms
Cell replication, Nutrition, Respiration, Excretion, Respond to environment, Movement within and externally, Grow in number and size.
What does a cell membrane do?
- The plasma membrane encompasses the functional cell unit
- Membranes segregate most other individual components of the cell
• Nucleus • Organelles
What is the cytoplasm/cytosol.
The fluid like matrix within the cell.
Why is mitochondria important?
Its main job is to produce ATP.
Its the only organelle that has its own DNA.
Clinically what is the significance of mitochondria?
Some diseases only effect the mitochondria.
ie- muscle disease.
Where does ones Mitochondrial DNA come from?
Mom. Mitochondria does not follow typical Mendalian genetics.
What are the unique characteristics of mitochondria?
-Contains its own DNA (maternal lineage only)
-Double membrane
•The inner memrane is heavily folded into "cristae"
• The gel-like fluid "matrix" contains enzymes for production of adenosine triphosphate (ATP)
Name an important site for ATP production/electron transport within the Mitochondria?
The Matrix (gelatinous material) which reside inside the cristae (invaginations) of the mitochondria.
What does the matrix inside the mitochondria have that helps make ATP?
Enzymes and coenzymes.
What three steps does a cell go through to make ATP?
1. Glycolysis. 2.Krebs cycle. 3. Electron transport chain.
Most basic. Take 6-Carbon sugar (glucose) and split into two 3 carbon (pyruvate) sugars. You also get a couple ATP out of the process. This is the set-up for the rest of cellular respiration. Gylcolysis does not need oxygen. But if you don't have Oxygen, the Krebs cycle and electron chain gets backed up.
When working out a lot, the body is not going to get enough oxygen. The blood flow going to them won't be able to deliver enough oxygen to the muscles. ie - lactic acid build up.
What is pyruvate?
A 3 carbon sugar that was obtained via glycolysis.
What happens to the 2 pyruvate that are obtained via the glycolysis?
Each pyruvate obtained through glycolysis goes through the Krebs cycle.
From that you get:
- 1GTP 3 NADH 1 FADH (x2)
What does NAD and FAD do?
Carry electrons.
What happens to NAD and FAD durning the Kreb cycle?
Electrons are attached and become: NADH and FADH
What is the importance of having a charged FADH or NADH?
The FADH and NADH are potential energy. The cell needs energy in order to live/function/react.
Where does glycolysis occur?
Where does the kreb cycle occur?
Inside the matrix of the mitochondria.
Where does the electron transport chain occur?
???The inner membrane of the mitochondria.
What happens when NADH and FADH go through the electron transport chain?
NADH and FADH go though electron transport chain. At the end of it, the hydrogens spit off to become a NAD or an FAD again. Oxygen has to be there to receive/cleve off the Hydrogen to become H2O and Co2. But what we get is ATP/energy out of the process!!! (NAD and FAD are recycled.)
How many ATP do you get per glucose?
36 to 38
Which step in cellular respiration is the majority of ATP produced?
Electron transport chain
What happens when there is no oxygen available to receive the NADH and FADH at the end of the Electron Transport Chain?
Cellular respiration back up and reverts back to Glycolysis.
How many ATP is produced from one NADH?
How many ATP is produced from one FADH?
Is NADH or FADH more efficient?
What is the cell membrane made of?
A bi layer of phospholipid. Phosphates, lipid and is in two layers. Lips and phosphats both outside and inside.
Are phospholipids amphipathic?
What are some characteristics of phospholipids.
Phospholipids are polar, having hydrophobic "tails" made of lipids, and hydrophilc "head" groups.

Because of this polar nature, phospholipids self-assemble in aqueous solutions to form bilayers.
Is the cell membrane selectively permeable?
yes. Lets some things into the cells (oxygen, water, ions) but not everything. Important for life.
What part of the cell membrane is the head?
Hydrophilc (water loving and POLAR, draws energy into celll) Head is composed of nitrogen and oxygen to make it polar.
What part of the cell membrane is the tail?
Hydrophobic (water fearing and NON POLAR) Tail is composed of methyl groups. The non polar tail makes it hydrophobic.
What determines whether or not an agent is easily absorbed by a cell?
It depends on the polarity of the agent.
Cell membrane characteristics
-Selectively permeable
-double layer
-has phosphates and lipids
-hydrophilic and hydrophobic part
What purpose does cholesterol serve in the body and cell?
Stiffens the membrane of the cell. Without cholesterol, cell would be very fluid like.
Needed for hormones.
What's the genetic code?
What is DNA?
Deoxyribonucleic acid. It makes up our genetic material.
Genes, chromosomes.
-Sugar phosphate backbone
-Inside of DNA is nucleic acid
- Adenine (A), Thymine (T) - double Hydrogen bonded
- Guanine (G), Cytosine (C) - triple Hydrogen bonded
Which hydrogen bond in DNA is easier to break?
The double bond of AT.
How many strands does RNA have?
What are the three types of RNA?
mRNA (messenger), tRNA (Transfer), rRNA (ribosomal).
What is the processes of making DNA to DNA called?
What is the processes of DNA to RNA called? (going towards making protein)
What is the process of going from RNA to protein called?
Translation or Protein synthesis
What is transcription?
Going from DNA to RNA
-DNA unzips and RNA is made to complement the single strand of DNA. Bonding ->AU (no T in RNA) CG
How do RNA and DNA differ?
-The sugar is different
-RNA is single stranded vs. Double
-RNA does not have thymine (T) It has Urisol.
What is endoplasmic reticulum ER?
A cell organelle. There is smooth and rough ER. It's a major sire of protein synthesis.
What does Rough ER mean?
There are ribosomes attached to the ER.
What does Smooth ER mean?
No ribosomes attached to the ER.
What is the function of ER?
- Protein synthesis (RER)
- Packaging of Protein
- Helps determien where the protein needs to go (say inside or go outside the cell)
Secretory Protein
- translocated freely into interior of the ER.
- Move to "smooth" ER section for encapsulation.
- Vesicle "pinched off" for secretion, or further processing at Golgi complex.
Transmembrane (within the membrane) proteins
- Translated into the ER membrane
- Membrane and protein is later incorporated into plasma membrane or membrane of other organelles
What tells the protein where it's going to go?
A messenger particles
Functions of Smooth ER
- Lipid synthesis
- Detoxifying
-Calcium Storage
What organ has a lot of SER?
The liver. SER helps detoxify.