Unit I (1-3)- Cell and General Physiology Flashcards
Sodium ions move out of the cell and potassium ions moves into the cell using the Na+K+ ATPase pump via __________.
A. Simple diffusion B. Facilitated diffusion C. Primary active transport D. Secondary active transport E. Osmosis
C Primary Active Transport
Ref: Guyton and Hall, 13th ed. pg. 55
________ carries the genetic code (codons complementary to that of DNA genes) from the nucleus to the cytoplasm for controlling the type of protein formed.
A. Precursor messenger RNA B. Small nuclear RNA C. Messenger RNA D. Transfer RNA E. Ribosomal RNA
C Messenger RNA
Ref: Guyton and Hall, 13th ed. pg. 31
Which of the following directs splicing of pre-mRNA to form mRNA?
A. snRNA
B. mRNA
C. rRNA
D. siRNA
A. snRNA
Guyton pg 31
The nucleolus is composed of:
A. clumps of heterochromatin
B. accumulations of histone proteins
C. aggregates of ribosomal RNA
D. damaged nuclear material
C aggregates of ribosomal RNA
Reference: Guyton and Hall, p. 32
The specificity of the potassium ion channel is attributable to:
A. pore loops containing carbonyl groups
B. diameter of the channel
C. amino acids with a strong negative charge lining the interior of the channel
D. the arrangement of hydroxyl groups within the channel
A pore loops containing carbonyl groups
Reference: Guyton and Hall, pp. 49-50
DNA is made up of nucleotides that have a complex relationship. What aspects of the compounds allows for DNA to maintain its characteristic structure and function?
A. The pliable structure allows a varying number of nucleic acids in each structural turn.
B. There are strong bonds between the two strands, making it sturdy.
C. Specific amino acids pair with one another, including adenine with thymine and guanine with cytosine.
D. The subunits of the DNA back bone are all made of deoxyribose, giving it stability.
C Specific amino acids pair with one another, including adenine with thymine and guanine with cytosine.
Reference: Guyton 2016 Ch. 3, Nucleotides (used online version of book, no page number)
The term autophagy refers to what cellular process?
A. The process by which newly formed organelles are transported within the cytosol.
B. The process by which the cell membrane lipid bilayer is repaired after a breach in integrity.
C. The process by which cellular organelles are repaired and restored after a chemical insult.
D. The process by which obsolete organelles and large protein aggregates are degraded & recycled by autophagosomes.
D. The process by which obsolete organelles and large protein aggregates are degraded & recycled by autophagosomes.
Pg. 20 Guyton
In the lower respiratory airways, ciliary movement is capable of moving the layer of mucus at a speed of ______ cm/minute.
1
2
4
6
1
Pg. 25
Guyton
The majority of ATP in the body is generated from:
A. Glycolysis
B. Citric acid cycle
C. Pentose phostphate pathway
D. Fatty acid beta-oxidation
B Citric acid cycle
Ref: Guyton and Hall P 23
The basic components of DNA include:
A. Phosphoric acid, a sugar (ribose), 4 nitrogen bases (A,T,G,C) which form nucleotides; these are bound together to form 2 strands of DNA bonded through weak cross-linkages
B. Phosphoric acid, a sugar (deoxyribose), 4 nitrogen bases (A,U,G,C) which form nucleotides; these are bound together to form 2 strands of DNA bonded through weak cross-linkages
C. Phosphoric acid, a sugar (deoxyribose), 4 nitrogen bases (A,T,G,C) which form nucleotides; these are bound together to form 2 strands of DNA bonded through strong cross-linkages
D. Phosphoric acid, a sugar (deoxyribose), 4 nitrogen bases (A,T,G,C) which form nucleotides; these are bound together to form 2 strands of DNA bonded through weak cross-linkages
D Phosphoric acid, a sugar (deoxyribose), 4 nitrogen bases (A,T,G,C) which form nucleotides; these are bound together to form 2 strands of DNA bonded through weak cross-linkages
Ref: Guyton and hall Figure 3.3 P27
Which of the following is found in higher concentrations in the intracellular fluid compared to the extracellular fluid?
A. Sodium
B. Potassium
C. Chloride
D. Bicarbonate
Answer: B. Potassium
Reference: Guyton 13th ed. Ch. 1 pg. 3-4; Ch. 4 pg. 48
Which type of RNA is a short single stranded fragment of RNA that plays a role in regulating gene transcription and translation?
A. Small nuclear RNA (snRNA)
B. Messenger RNA (mRNA)
C. MicroRNA (miRNA)
D. Transfer RNA (tRNA)
Answer: C. MiRNA
Reference: Guyton 13 ed. Ch. 3 pg. 31-33
What is the function of transfer RNA?
A. To carry the codons through the ribosome for translation
B. To attach to the gene promoter for initiation of transcription
C. To cause attachment of a specific amino acid to a forming protein chain
D. To regulate gene expression by binding to the complementary region of the RNA
Answer: C To cause attachment of a specific amino acid to a forming protein chain
Guyton and Hall Textbook of Medical Physiology, 12th ed., p. 32
Regarding transport of substances through the cell membrane, what characterizes active transport ?
A. It is mediated by a carrier protein.
B. It is selective of specific substances.
C. It relies on a concentration gradient.
D. It requires an additional source of energy.
Answer: d It requires an additional source of energy
Guyton and Hall Textbook of Medical Physiology, 12th ed., p. 46
Which of the following is true regarding miRNAs role in RNA processing?
I.They direct the splicing of non-coding interons from pre-mRNA to form mRNA
II. When complexed with RISC, they act to degrade mRNA before it can undergo translation
III.They require activation by DICER to be functional within the cytoplasm
A. I and II
B. I and III
C. II and III
D. I, II, and III
Answer C II and III
II. When complexed with RISC, they act to degrade mRNA before it can undergo translation
III. They require activation by DICER to be functional within the cytoplasm
Guyton Chapter 3 fig. 3-10
Which of the following are normal functions of the Na/K ATPase?
I. Maintenance of normal cell volume
II. Production of ATP
III. Production of an electrical gradient
A. I and II
B. I and III
C. II and III
D. I, II and III
Answer D I, II, III
I. Maintenance of normal cell volume
II. Production of ATP
III. Production of an electrical gradient
Guyton Chapter 4 section on active transport (near fig. 4-12)
This organelle functions to be the intracellular digestive system containing hydrolase enzyme granules…
A. Agranular endoplasmic reticulum
B. Lysosomes
C. Peroxisomes
D. Ribosomes
Answer: B Lysosomes
Chapter 2. Guyton and Hall 13th Edition
In which phase of the cell life cycle is the nuclear envelope broken as microtubules attach to the chromatids, pulling them apart?
A. Prophase
B. Prometaphase
C. Metaphase
D. Anaphase
Answer: B Prometaphase
Chapter 3. Guyton and Hall 13th Edition
Translation is the process by which:
A. RNA is formed using DNA as a pattern within the cell nucleus
B. Water soluble substances are transported across a phospholipid membrane
C. Chromosomes are condensed during mitosis
D. Proteins are synthesized using RNA as a template
Ch 3, pg 30 Guyton
Correct answer: D Proteins are synthesized using RNA as a template
What is the primary function of the Na-K-ATPase pump?
A. Move 3 Sodium Ions into the cell and 2 Potassium ions out of the cell
B. Move 2 Sodium ions into the cell and 3 Potassium ions out of the cell
C. Move 2 Sodium ions out of the cell and 3 Potassium ions into the cell
D. Move 3 Sodium ions out of the cell and 2 Potassium ions into the cell
Guyton Ch 4, pg 55
Correct answer D 3 Na out and 2 K in
Which of the following is a single-stranded RNA important for regulating gene expression? A. Ribosomal RNA B. microRNA (miRNA) C. Transfer RNA (tRNA) D. Messenger RNA (mRNA)
B. miRNA
Guyton, Chapter 3
The process of glycolysis takes place in which of the following cell components?
a) Mitochondria
b) Golgi apparatus
c) Cytoplasm
d) Endoplasmic reticulum
Correct Answer: c
Guyton Chapter 2, The Mitochondria Extract Energy from Nutrients: Chemical Processes in the formation of ATP- Role of Mitochondria
Each purine base adenine of one DNA strand always bonds with which of the following?
a) Thymine
b) Guanine
c) Cytosine
d) Uracil
Correct Answer: a
Guyton Chapter 3, Genes in the Cell Nucleus Control Protein Synthesis: Nucleotides Are Organized to Form Two Strands of DNA Loosely Bound to Each Other
During which phase of mitosis are the two chromatids of each chromosome pulled apart yielding two separate sets of daughter chromosomes? A. Prophase B. Metaphase C. Anaphase D. Telophase
B. Metaphase
Guyton Chapter 3, Cell Mitosis
% body fluid in intracellular/extracellular space
1/3 extracellular| 2/3 intracellular
Higher in extracellular or intracellular fluid:| Amino acids, bicarbonate, chloride, fatty acids, glucose, magnesium, oxygen, phosphate, potassium, sodium
Intracellular - potassium, magnesium, phosphateExtracellular - sodium, chloride, bicarbonate, oxygen, glucose, fatty acids, amino acids
Formula for gain
Gain = Correction/Error
Where are sphingolipids most numerous
Nerve cells
Sphingolipid functions (3)
Protection from harmful environmental factorsSignal transmissionAdhesion site for extracellular proteins
Functions of glycocalyx (4)
Negative charge - repels other negatively charged objectsSite of attachmentReceptorsImmune reactions
Function of SER
Lipid synthesis
Golgi function
Processing substances from ER| Forming lysosomes, secretory vesicles and cytoplasmic components
Lysosome function
Intracellular digestive system - digest damaged cellular structures, food particles and bacteria
Enzyme in lysosomes
Hydrolase
Differences between peroxisomes and lysosomes
Formed by self replication or budding off SER (vs Golgi)Contain oxidases (vs hydrolases)Oxidases form hydrogen peroxide, acts in combination with catalase to oxidise otherwise poisonous substancesMajor function to catabolise long chain fatty acids
Mitochondria structure
2 lipid bilayer protein membranes - outer and innerInner folded - cristae - oxidative enzymes attachedInner cavity filled with matrix - contains dissolved enzymes
Where are mitochondria formed
Self replicative
What is the nucleolus
An accumulation of large amounts of RNA and proteins
How are lysosomes adapted to kill phagocytksed bacteria?
Lysozyme - dissolves cell wallLysoferrin - binds ironAcid - pH 5 => activates hydrolases
What organelle is responsible for glycogen breakdown
Endoplasmic reticulum
What are the 2 main functions of the Golgi apparatus?
1 - additional processing of substances formed in the ER (by adding CHO and compacting)2 - CHO synthesis (hyaluronic acid and chondroitin sulphate)
ATP structure
Adenine - nitrogenous baseRibose - pentose sugar3 x phosphate radicals
Where do the different stages of glucose metabolism occur in the cell and how much do they account for overall glucose metabolism?
Glycolysis - cytoplasm - 5%| CAC/Kreb’s cycle - mitochondria - 95%
DNA components
Phosphoric acidDeoxyriboseNitrogenous base
Purine bases
Adenine and guanine
Pyrimidine bases
Thymine and cytosine
DNA base pairing
A - T| G - C
How many nucleotide pairs are in each full turn of the DNA helix?
10
Define transcription and translation
Transcription - DNA => RNA| Translation - RNA => protein
RNA components
RibosePhosphoric acidNitrogenous base
RNA bases
Guanine, cytosine, adenine, uracil
Describe the process of activation of RNA nucleotides
Activated by RNA polymerase - adds 2 phosphate radicals to each nucleotide to form triphosphatesLast 2 phosphates combined by high energy phosphate bonds => large quantities of ATP energy made available to nucleotides
What enzyme is responsible for RNA assembly
RNA polymerase
What are the different types of RNA?| What are their functions?
1 - precursor messenger RNA - processed in the nucleus to form mature messenger RNA2 - small nuclear RNA - directs splicing of pre-mRNA to form mRNA3 - messenger RNA - carries genetic code to cytoplasm4 - transfer RNA - transports activated amino acids to ribosomes5 - ribosomal RNA - forms ribosomes6 - micro RNAS - regulate gene transcription and translation
Where are ribosomes formed?
Nucleolus
How are miRNAs formed?
Primary precursor RNA - processed in cell nucleus by microprocessor complex to pre-miRNAsPre-miRNA further processed in cytoplasm by dicer enzyme - helps assemble RNA-induced silencing complex and generated miRNA
Where is the microprocessor complex found?
Nucleus
Where is dicer enzyme found?
Cytoplasm
How to miRNA regulate gene expression
Bind to complementary RNA and promote repression of translation or degradation of RNA
What is small interfering/silencing RNA?
Short, double stranded RNA molecules that interfere with gene expressionNormally synthetic
Which enzyme forms peptide bonds during translation
Peptidyl transferase
What are the stages of DNA replication?
1 - DNA helicase unzips DNA2 - DNA primase generates RNA primer - binds at starting point of replication3 - DNA polymerase adds nucleotides4 - DNA ligase bonds nucleotides5 - termination - exonuclease removes primers, replaced with bases. Exonuclease also proofreads
What are Okazaki fragments?
Pieces of DNA between primers not yet bound to remainder of stand
What is the function of topoisomerase?
Acts during DNA replication, prevents DNA in front of replicative fork becoming overwound
What are histones? What is their function?
Small molecules of electropositivity. DNA helix coiled around. Regulate DNA activity, when DNA is tightly packaged cannot function as template for RNA formation or DNA replication
What are the stages of mitosis?
Interphase - interval between mitosis. Towards the end centrioles form in cytoplasm. Before mitosis centrioles move apart and microtubules grow away from centrioles forming asterProphase - chromosomes condensePrometaphase - micro tubular spines of the aster penetrate the nucleus and attach to chromatids at the centromere. Metaphase - asters move further apartAnaphase - chromatids pulled apart at the centromereTelophase - mitotic apparatus dissipates, new nuclear membrane forms and cell pinches in two
What are telomeres?
Region of repetitive nucleotide sequences at the end of a chromatid - serve as protective caps
Where/when is telomerase found?
Stem cells, germ cells, cancer cells
Briefly, what is transcription?
DNA => RNA
Briefly, what is translation?
RNA => Protein
