Cellular and Molecular Basis Flashcards
What are the the two fluids that make up your body composition?
Intracellular Fluid (ICF) Extracellular (ECF)
What fraction of total body fluid does ICF make up? What fraction does does ECF make up?
ICF - 2/3
ECF - 1/3
fluid found inside of cells
ICF
fluid found outside of cells (fluid between cells ex: edema and fluid of blood predominantly plasma)
ECF
What % of body weight does ECF and ICF make up?
55-65%
What is the primary cation of ECF?
sodium
What is the primary cation of ICF?
potassium
when giving fluids, would you get NaCl or KCl? and why?
We must give sodium chloride when giving fluids bc sodium is the primary EC cation. Don’t give KCL bc could cause arrhythmia bc not use to having high K in ECF
What is the primary anion of of ICF?
phosphate
What is the primary anion of ECF?
chloride
What is critical to maintain the ph of the body?
bicarbonate
Which fluid contains the most protein? Are these proteins positively or negatively charged? Why?
ICF
Protein in ppl are negative charge and many drugs are positively charged so can match with protein to inactivate
What are the electrolytes found in body fluid?
Anions(-) and cations(+)
What is osmolar concentration?
Osmolar Concentration-# of particles found within a solution
What is the osmolality formula made up of?
sodium, glucose and blood urea nitrogen(BUN)
The osmolality of fluids affects ______ across cell and other semi-permeable membranes. However, biological membranes restrict _____.
water movement ;
particles like Na and K
If you stick a cell in a hypertonic solution what will happen?
shrink
If you stick a cell in a hypotonic solution what will happen?
swell/burst
If you stick a cell in a isotonic solution what will happen?
nothing. stay the same
Energy is transferred to coenzyme acceptors such as _____ for use in _______ to generate compounds with high-energy phosphate bonds (ATP, GTP, CoA)
NAD, NADP, FAD;
oxidative phosphorylation
What is the ultimate source of energy for biological reactions?
high energy phosphate bonds like ATP, GTP, CoA
Where does glycolysis occur and what does it produce? Is oxygen needed?
Glycolysis makes 2 ATP per glucose and occurs in the cytoplasm; doesn’t need mitochondria or oxygen for this process
Where does the krebs citric acid cycle occur and what does it produce? Is oxygen needed?
in the mitochondria;
36 ATP/glucose;
yes oxygen is needed
What is glycogenolysis?
the breakdown of the molecule glycogen into glucose, a simple sugar that the body uses to produce energy
what is gluconeogenesis?
formation of glucose within the body from precursors other than carbohydrates especially by the liver and kidney using amino acids from proteins, glycerol from fats, or lactate produced by muscle during anaerobic glycolysis
Where does B-oxidation occur and what happens?
Beta-oxidation is the catabolic process by which fatty acid molecules are broken down in the mitochondria to generate acetyl-CoA, which enters the citric acid cycle, and NADH and FADH2, which are co-enzymes used in the electron transport chain.
Fatty acids are carried from cytosol into mitochondria by _____ where they are metabolized
fatty acyl carnitine
______ in the blood or urine suggests that fat is being metabolized at a high rate. What does this mean?
ketones; too much acetyl-CoA is being produced so instead of entering krebs cycle it enters ketogenesis
side note: A person may be trying to by diet or they may not have enough insulin (diabetes patient).
when ketones are released–> 1. we are oxidizing lipids at a high rate 2. we don’t have sufficient carbs to use all those lipids for energy generation
What are two liver function tests? What are these?
AST (Aspartate Aminotransferase) and ALT (Alanine Aminotransferase)
Transaminases
Getting energy from protein would be involved in what process?
gluconeogenesis
What process cuts off that NH2 group that can later form ammonia(highly toxic) and can dissolve membranes?
deamination
Where does the urea cycle occur? What happens?
Liver;
ammonia is created from deamination. NH4+ enters the urea cycle and turns into urea which is excreted through the urine
DNA is formed from 2 chains of nucleotides which bind together in a helical form by H bonds. What are the 2 chains of nucleotides?
Adenine and thymine; cytosine and guanine
The superstructure of chromosomes is held together with ____ and ______
histones and other proteins
_____ are discontinuous sequences of DNA which code for the amino acid sequence of a single peptide chain
genes
What is an example of a regulatory element?
promoter
What is thymine replaced with when DNA changes to RNA?
uracil
____ is formed from a single chain of nucleotides formed from DNA template
RNA
List the three types of RNA. What does they do?
Messenger RNA (mRNA) transcribed from DNA (via pre-mRNA which requires processing)--convey genetic information from DNA to the ribosome, where they specify the amino acid sequence of the protein products of gene expression. Transfer RNA (tRNA) transports specific amino acids to the site of protein synthesis on ribosomes Ribosomal RNA (rRNA) uses mRNA to arrange amino acids in the proper order to form a protein
Cystolic proteins are released directly into what?
cytosol
Where are secreted proteins released?
endoplasmic reticulum
Give a brief description of transcription and translation
Transcription-It is the transfer of genetic instructions in DNA to messenger RNA (mRNA). mRNA formed in transcription is transported out of the nucleus, into the cytoplasm, to the ribosome (the cell’s protein synthesis factory). The process by which mRNA directs protein synthesis with the assistance of tRNA is called translation. Translation is the process of translating the sequence of a messenger RNA (mRNA) molecule to a sequence of amino acids during protein synthesis
The ______ are the base for nucleic acid (DNA, RNA) formation.
nucleosides
The _____ are phosphorylated nucleosides
nucleotides
The waste product of nucleotide degradation is ____ (associated with ____).
uric acid; gout
Cell membranes are _____ with variable amounts of ___ and _____
phospholipid bilayers;
cholesterol and protein
Cell membranes are _____ with variable amounts of ___ and _____. They are very ____ active.
phospholipid bilayers;
cholesterol and protein;
metabolically
What are the two kinds of proteins?
integral (penetrate into membrane) or peripheral (associate with membrane surface)
Many proteins have _______, increases hydrophilicity and affects function
carbohydrates attached (glycoproteins)
lysosomes are formed from what?
the golgi apparatus
lysosomes contain multiple ______ for digestion of organic molecules
lytic enzymes
What do cytoskeletal proteins do?
maintain cell shape, allow movement, facilitate cell polarity and cytosolic transport
what are muscular motors? What do they form?
Proteins/organelles which allow movement made of proteins such as actin, myosin, dyenin, kinesin. They form cilia, flagella, and muscle contractile elements
What are intercellular junctions?
Cell-cell junctions allow organ formation and cell interactions
What are some different types of intercellular junctions?
- Tight junctions (highest strength)
- Desmosome and zona adherens (some strength but less than tight junctions)
- Gap junctions allow small molecule passage
- Hemidesmosome helps adhere to basal lamina
What does the nucleus contain?
chromatin (condensed chromosomes) and nucleolus (RNA rich regions)
The nuclear membrane is continuous with the _____.
Endoplasmic reticulum
Protein secretion occurs via connection of ____ with golgi
Rough endoplasmic reticulum
Which part of the ER is involved with steroid synthesis?
Smooth ER
Which part of the ER is involved with secreted protein synthesis?
Rough ER
Which part of the ER has ribosomes?
rough
Normal somatic cells are _____. How many chromosomes?
diploid;46 chromosomes = 23 chromosome pairs per parent
Which is a non-germ cell? What kind of cell division occurs?
Somatic; mitosis
Briefly describe the phases of mitosis
G0 phase: Quiescent, non-proliferative, normal state for most cells (diploid, 23 chromosome pairs in humans, i.e., 46 total)
G1 phase: Initial cell growth, mostly protein and lipid production
S phase: DNA synthesis occurs to form tetraploid cells (twice as much DNA as normal, enough for 2 cells)
G2 phase: Continued cell growth before division
M phase: Mitosis, with cell division to 2 diploid cells
What cell is a germ cell?
gamete
briefly describe meiosis
Similar to mitosis through G2 phase but paired chromatids separate to form 4 haploid cells (23 chromosomes total)
2 stages – Miosis 1 and miosis 2. In meiosis I, homologous chromosomes separate, while in meiosis II, sister chromatids separate. Meiosis II produces 4 haploid daughter cells, whereas Meiosis I produces 2 diploid daughter cells.
