Introduction And Cell Biology Flashcards
Smallest form to replicate on its own
Cell
How many cell types in human body?
200+
Has 2 layers of phospholipid molecules
Cell membrane
Is phosphate head in the cell membrane hydrophilic or hydrophobic?
Hydrophilic
What can travel easily through cell membrane?
H20, CO2
What needs protein channels to travel across cell membrane?
Glucose and sugars
Microtubules, microfilaments and intermediate filaments are proteins that form what in the cell?
Cytoskeleton
what is intracellular fluid with Na and K?
Cytosol
Organelles with cytosol
Cytoplasm
Contains genetic material in cell
Nucleus
Like “books” in nucleus
Genes
Like words in the books in the nucleus
DNA
DNA is one long molecule that coils around proteins called
Histones
Tightly folded DNA is called a
Chromosome
Many chromosomes that form a shapeless mass of DNA in the nucleus is called
Chromatin
What does DNA have to be transcribed into to make a particular protein?
RNA
What use MRNA copies to make a protein?
Ribosomes
What structure inside the nucleus makes ribosomes?
Nucleolus
What is the nucleolus made of?
RRNA + proteins
What is called the “workshop” in the nucleus?
Nucleolus
What is made when a ribosome converts a string of MRNA?
Amino acid
The process for making an amino acid is called what?
Translation
A sequence of 3 bases which code for a specific amino acid.
Codon
What does rough endoplasmic reticulum do?
Translates MRNA into a protein
What makes the surface of the rough endoplasmic reticulum rough?
Ribosomes
What in the cell makes lipids, like cholesterol and phospholipids
Smooth endoplasmic reticulum
What takes proteins, lipids and hormones and stores them in a vesicle in the cell?
Golgi apparatus
What type of vesicle moves within the cell?
Transport
What type of vesicle moves molecules out of the cell?
Secretory
Energy source in cell
Mitochondria
When glucose in cytoplasm goes through glycolysis, what is made?
ATP
What is formed during glycolysis when 6-carbon glucose is cleaved into 2 halves?
Pyruvate
During citric acid cycle, one glucose yields how many ATP?
32
What does citric acid cycle need to form ATP?
Oxygen (aerobic)
What is another name for Citric Acid Cycle?
Kreb’s Cycle
When mitochondria use medium-sized fatty acids for fuel in the absence of enough glucose
Beta oxidation
In a phospholipid, the head is made of?
Phosphate
What is the tail of a phospholipid made of?
Fatty acid
Skeleton of a phospholipid is made of?
Glycerol
What cannot freely pass through cell membrane?
Highly polar, charged molecules (Na, K, Cl)
Cholesterol keeps cell membrane from getting what in low temperatures?
Brittle
True/false: Cholesterol keeps the cell membrane together in high temperatures
True
Which cell has high level of cholesterol in its membrane to keep it durable through wear and temp changes?
Red blood cell
Protein that spans across cell membrane
Integral
Holds cells to each other
Adherens junctions
Example of a cell surface receptor
Insulin receptor
H2O molecules travel across a semi permeable membrane that separates 2 solutions
Osmosis
Equal concentrations on both sides of a membrane
Isotonic
Net zero movement across membrane
Equilibrium
More solute than other side
Hypertonic
Less solute than other side
Hypotonic
3 types of Molecules that can cross cell membrane
Small, non-polar (O2)
Small, polar (H2O)
Large non-polar (vitamin A)
2 molecules that can’t cross cell membrane alone
Highly polar, charged ions (N, K)
Large, polar (glucose)
What carrier does Glucose use to cross membrane
Glucose transporter
How does water pass through membrane?
Aquaporins
How does Cl- pass through membrane
Chloride channels
Bulk transport processes that need ATP to move high volume of molecules across membrane
Endo and exocytosis
What is known as “cell drinking”
Pinocytosis
When white blood cells and macrophages look for debris to “eat”
Phagocytosis
What part of the cell starts exocytosis?
Golgi aperatus
True/False: exocytosis requires ATP
True
3 major molecules that make up extracellular matrix
1) adhesive proteins
2) structural proteins
3) proteoglycans
Proteins that anchor cells together and to other molecules in ECM
Adhesive proteins
3 structural proteins
1) collagen
2) elastin
3) keratin
Most common protein in the body
Collagen
Protein that resists tension and stretches
Collagen
3 polypeptide precursor to collagen
Procollagen
3 strands of twisted procollagen form what?
Super helix
When ends of super helix are trimmed by enzyme (collagen peptidase), what is formed?
Tropocollagen
Stacks of tropocollagen form what?
Collagen fibrils
Bunched up collagen fibrils form what?
Collagen fiber
Type of collagen that forms skin, bone and tendons
Type 1
Type of collagen that forms cartilage
Type 2
Type of collagen that forms mesh work (reticulin) found in liver, lymph and blood vessels
Type 3
Type of collagen that forms basement membrane that separates different types of cells (eg nerve and muscle)
Type 4
Protein that helps regain shape
Elastin
Tough protein in hair and nails
Keratin
Protein core attached to a sugar chain (GAGs) that cushions and hydrates cells (a lot in cartilage)
Proteoglycans
3 proteins that make up cytoskeleton
Actin
Intermediate filaments
Microtubules
What part of RNA is eliminated after transcription before translation?
Introns
Which molecules can cross plasma membrane by simple diffusion?
Lipid soluble
Non polar
Hydrophobic
The sequence of nucleotides in mRNA is identical to which DNA strand?
Coding strand
Clatherin proteins form a shell around a vesicle in what kind of endocytosis?
Receptor mediated
Two types of adhesive proteins in cells
Intergrins
Cadherins
Thinnest protein in cytoskeleton
Actin
Where are actin filaments in cell located?
Below cell membrane
WBCs use this to “crawl” in and out of blood vessels
Pseudopodia
The process that allows WBCs to crawl in/out of blood vessels
Diapedesis
Thickest structure in cytoskeleton
Microtubules
A single Microtubule is made up of how many protofilaments?
13
Act like railroad tracks in the cell
Microtubules
What is located at base of flagella and cilia that assist movement?
Centrioles
Where in the body are non-motile cilia located?
Rods in eyes
Where in body are motile cilia located?
Lining of fallopian tubes
Part of cytoskeleton that fastens organelles, anchors cells to each other and environment.
Intermediate filaments
What do type 1 & 2 microfilaments make?
Keratins
What chops long fatty acids to medium size and creates hydrogen peroxide?
Peroxisomes
What do peroxisomes do to free radicals that is produced in metabolism?
Neutralizes free radicals
What does amphipathic mean?
One end of molecule is different than other. (Hydrophobic/hydrophilic)
3 types of passive transport
Simple diffusion
Facilitated diffusion
Osmosis
How do small, non-polar travel down a concentration gradient?
Simple diffusion
How do larger molecules travel down a concentration gradient across a membrane?
Facilitated diffusion via channel or protein carrier
2 types of active transport
1) primary
2) secondary
What does primary active transport need?
ATP
Enzymes (ATPase)
Example of primary active transport
ATPase sodium potassium pump
What does secondary active transport use as a source of energy?
Energy stored in concentration gradients
Example of secondary active transport
Sodium glucose transporter (SGLT1)
Most common classification of a intermediate filaments?
Vimentin (smooth muscle, fibroblasts, WBCs)
Which bases in DNA bind to each other?
A-T, C-G
What are the pyrimidines
Cytosine
Uracil
Thymine
How many H in A-T bond in DNA?
2
How many H in C-G bond in DNA
3
What is DNA wrapped 2 times around group of 8 histones called?
Nucleosome
What is a group of Nucleosomes?
Chromatin fibers
Loosely packed chromatin fibers used by genes daily?
Euchromatin
Tightly packed chromatin fibers seldom used by genes
Heterochromatin
How many DNA molecules in chromatids
46
First step of DNA to protein
Transcription
What happens during transcription?
Gene is read and copied on individual mRNA molecule
How many types of nucleotides on a single strand of DNA
4
What is coding strand of DNA also called?
Sense Strand
What is the Template Strand of DNA also called?
Anti-sense strand
Which strand of DNA serves as the master blueprint
Coding strand
Which DNA strand has a sequence of complementary nucleotides to coding strand?
Template
Which direction does coding strand if DNA run?
5’ - 3’
What is 1st step of transcription?
Unpacking of DNA from chromatin
What process uses RNA polymerase enzyme to shear H bonds between DNA strands
Elongation
How many base pairs of are in each “transcription bubble” DNA is unzipped
14
What does RNA polymerase do to template strand after “unzipping” it?
Assembles mRNA molecule
In mRNA, what is T base replaced by?
Uracil
What do ribosomes make proteins out of?
Amino acids
What is mRNA molecule a mirror image of?
Template strand
What is starting point for transcription on DNA where RNA polymerase binds?
The promoter
What do genes code for?
Protein
What is it when ribosomes assemble proteins from amino acids in cytoplasm?
Translation
How many nucleo bases (codons) = 1 amino acid
3
How many combos can 4 nucleotides be combined
64
What is it called when ribosome grabs mRNA
Initiation
What is typically a “start codon”
AUG
what are the stop codons in translation?
UAA
UGA
UAG
What is it called when ribosome encounters stop codon
Termination
What brings amino acids to the ribosome?
Transfer RNA (tRNA)
