A&P TEST 3 Flashcards
What does cellular respiration do?
it’s how cells make ATP
Overall is cellular respiration endergonic or exergonic?
exergonic
How is energy released during cellular respiration?
through potential energy in chemical bonds, when broken energy is released
The energy released is used to synthesize ATP which is what type of reaction? exergonic or endergonic?
- endergonic, energy requiring process
Is oxygen required for cellular respiration?
yes
What is the formula for glucose oxidation?
C6H12O2 + 6 O2 —> 6 CO2 + 6 H2O
In words, what is the formula for glucose oxidation?
glucose + oxygen yields carbon dioxide and water
Some of the energy of broken bonds captured to
attach what group to ADP
phosphate group
What are two ways that phosphorylation occurs?
substrate-level phosphorylation and oxidative phosphorylation
What is substrate-level phosphorylation ?
direct synthesis of ATP
What is oxidative phosphorylation?
energy first released to coenzymes (e.g., NAD+, FAD)
• that energy then transferred to form ATP
What type of phosphorylation is more common?
oxidative phosphorylation
What type of enzyme does substrate- level phosphorylation use?
KINASE enzyme
Enzymes for glucose oxidation are found in both:
The cytosol, semifluid cell contents
– The mitochondria, small organelles within the cell
Stages of glucose oxidation:
Glycolysis, Citric acid cycle and electron transport system
Where do each of the stages of cellular respiration occur?
- glycolysis - cytosol
- Citric acid cycle in the matrix of the mitochondria
- ETS in the cristae of the mitochondria
Which stages are anaerobic vs aerobic?
anaerobic = glycolysis aerobic = CAC and ETS
What’s needed for glycolysis to occur?
1 glucose molecule
2 NAD + molecules
2 ATPs
What does glycolysis yield?
NET 2 ATps
2 NADHs
2 Pyruvate molecules
The pathway of glycolysis consists of how many enzymes?
10
If there is no oxygen available once pyruvate is made what happens? What if there is oxygen available?
If sufficient O2 available, pyruvate enters mitochondria
– If insufficient O2 available, pyruvate converted to lactate
What is lactate?
the thing that makes our muslces sore and that our heart likes
What is the second step of cellular respiration?
the citric acid cycle (also called the Kreb’s cycle)
What is required for the citric acid cycle to occur?
Acetyl CoA
How is Acetyl CoA made?
from oxidizing pyruvate
What does the citric acid cycle yield?
2 ATP
8 NADHs
2 FADH
What is important to remember during the citric acid cycle and the ETC?
that because glycolysis made TWO pyruvates they each go through the steps (yielding twice as many molecules)
….for example each citric acid cycle only yields 1 ATP but bc it happens twice is why it yields 2
Where do NADH and FADH go?
to the ETC
How many enzymes are used during the CAC?
9
What is acetyl CoA converted to within the cycles?
2 carbon dioxide molecules
What does the electron transport chain do?
Involves the transfer of electrons from NADH and FADH2 • energy released used to make ATP
What’s the simplified steps of the ETC?
electron carriers, H+
pumps, ATP
synthetase enzymes
Whats the final electron acceptor of the ETC? and why is this significant?
Oxygen, if O is not available the etc will back up
What does cyanide do to the ETC?
blocks oxygen form accepting electron which means cell depends on glycolysis and cannot make enough energy from glycolysis alone
What are the other two fuel molecules that can be oxidized to generate ATP?
Fatty acids and proteins
When do the other fuel molecules increase?
during conditions of starvation
Fatty acids are the prefered molecules for what? What type of energy does it provide and where in cellular respiration does it come in at?
- preferred molecules for muscle tissue at rest
- long term energy storage as triglycerides
- comes in the at citric acid cycle as acetyl CoA
Where do proteins enter the cellular respiration? And what happens to the amine group if it’s used as a fuel molecule?
different amino acids enter pathway at different points, the amine group is removed and waste converted to urea and excreted
When is proteins used as fuel?
only in emergencies as a last resort
What are cells known as?
the functional units of the body
What is the study of cells?
cytology
Who was Galileo, Robert Hook and Antonie Van Leeuenhoek ?
Galileo was involved with ballistics and optics invented the telescope
- Hook made the first microscope and coined the term CELL
- Leeuenhoek was the first t see bacteria under microscope
What are the two categories of microscopes?
Light microscope, electron microscope
How does a light microscope work?
produces a TWO DIMENSIONAL image, light passed through lens, staining is used for contrast
Whats an electron microscope?
It’s similar to the light microscope but uses beam of electrons instead of light
Why is an electron microscope more advanced?
it produces better image
- greater magnification
- greater ability to see detail
What are the two types of electron microscopes?
Transmission electron microscope and scanning electron microscope
Whats a TEM?
– Directs an electron beam through thin cut sections
– Produces two-dimensional images
Whats an SEM?
– Directs an electron beam across the surface of a specimen
– Generates a three-dimensional study
What is the plasma membrane?
Forms the outer limiting barrier
What does the plasma membrane separate?
Separates internal contents of cell from external environment
(inside = interstital fluid)
(outside = extracellular fluid)
What are the equal parts of the plasma membrane (by weight)?
Lipids and proteins
What are the two types of models that were based on the structure of the plasma membrane? which is the correct model?
Sandwich model
- Fluid mosaic model
Why was the fluid mosaic model correct?
bc it has the molecules int he membrane moving relative to each other
- strong evidence for fluidity of membrane
Is the plasma membrane polar or non polar?
non polar
What are the different types of lipids the plasma membrane contains?
phospholipids, cholesterol, and glycolipids
Most membrane lipids are what?
phospholipids
What is the sheet like structure of phospholipids called?
phopholipid bilayer
What do the phospholipid bilayer ensure?
Ensures cytosol and fluid surrounding cells remain separate
Where is cholesterol in the bilayer located and what does cholesterol do for membrane?
- Scattered within phospholipid bilayer
– Strengthens the membrane
– Stabilizes the membrane against temperature extremes
What are glycolipids? Where are they located and what do they help form?
- Lipids with attached carbohydrate groups
– Located on outer phospholipid region only
– Helps to form the glycocalyx
What does glycocalyx do?
acts as a name tag allowing our body to see which cells belong to us and which might be invaders
Membrane proteins compose what amount of the plasma membrane by weight?
half
How are membrane proteins presented in the bilayer?
they can float and move aobut the fluid bilayer
Most of a membrane’s functions are determined what?
resident proteins
How membrane proteins classified pertaining to the location on the membrane?
as integral or peripheral proteins
Where are integral proteins?
Embedded within and extend across lipid bilayer
Because integral proteins are within the bilayer what two parts do they consist of ?
hydrophobic and hydrophilic
Integral proteins are often what type of proteins with what attached to it?
glycoproteins with carbohydrate portion`
Where are peripheral proteins located?
– Not embedded in lipid bilayer
– Attach loosely to surfaces of the membrane
What are the functional categories of the membrane proteins?
- transport proteins
- cell surface receptors
- identity markers
- enzymes
Transport proteins do what? list 3 examples..
regulate movement of substances across membrane
• e.g., channels, carriers, and pumps
Cell surface receptors do what? list 2 examples…
bind ligand molecules released from a specific cell
• bind receptors on another cell
• e.g., neurotransmitters and hormones
Identity markers do what? give an example…
communicate to other cells
• e.g., immune system cells distinguishing healthy cells from foreign cells
Enzymes do what?
catalyze chemical reactions
Membrane transport is a process that does what for the plasma membrane?
Regulating movement of materials into and out of a cell
What can go through the bilayer without being transported?
small and nonpolar molecules like CO2 and O
Membrane transport can be what or what?
active or passive
Passive process of membrane transport does not require what and what does this depend on? list two types of passive processes…
- does not require energy
- dependent on substances moving DOWN concentration gradient
- diffusion and osmosis
Active process of membrane transport requires what and what type of movement is this? list two types of active processes…
- requires energy
- movement of substance UP it’s concentration gradient
- active transport and vesicular transport
Diffusion:
- Describes net movement of a substance
– Moves from area of greater concentration to area of lesser
concentration
If unopposed diffusion continues until what?
equilibrium
What are the two environmental conditions that affect diffusion? both of these cause what rate of diffusion
- “Steepness” of concentration gradient
- temperature
*both cause faster rate of diffusion
What are the two types of diffusion?
simple diffusion and facilitated diffusion
Simple diffusion can be compared to what? Is energy required?
ball rolling down the hill
- no energy required
Facilitated diffusion can be compared to what? Is energy required?
ball being pushed up hill
- energy required
What are the two types of facilitated diffusion?
- channel-mediated diffusion
• carrier-mediated diffusion
Channel- mediated diffustion is:
Movement of small ions through water-filled protein channels
– Channels specific for one ion type
What are the two types of channel- mediated diffusion?
leak channels and gated channels
Whats the difference between leak channels and gated channels?
leak channels are continuously open
- gated channels are usually closed and open in response to stimuli
Carrier mediated channels do what?
- moves substance down gradient,
- Binding of substance causing change in carrier protein shape
Osmosis is what?
the passive movement of water through selectively permeable membrane
Water follows what during osmosis?
the solutes
Tonicity is what?
the number of solutes
Does the type of solutes mater with osmosis and tonicity?
no, only the number matters
What are the two types of solutes with the selectively permeable membrane?
- permeable solutes and nonpermeable solutes
Permeable solutes include?
small and non polar
Nonpermeable solutes include?
large, charged and polar
A greater concentration solutes leads to what type of concentration with water?
lesser concnetration of water
Osmotic pressure is what?
Pressure exerted by movement of water across semipermeable membrane
Isotonic is what net movement of water?
no net movement, equal number of solutes and solution
What is the isotonic solution for erythrocytes?
0.9% NaCl
Hypotonic is what number of solutes? because water followers solutes what can this cause?
- low number of solutes outside the cell
- water followers solutes inside the cell causing the cell to burst (hemolysis)
Hypertonic solution is what number of solutes? Because water followers the number of solutes what can this cause?
high number of solutes outside the cell
- water followers solutes outside the cell causing cell to shrink (crenation)
How does active transport solutes move?
it moves against a concentration gradient
Primary active transport uses energy directly or indirectly to break down ATP?
directly
How does primary active transport work?
- adds phosphate group to transport protein, changes it shape, moves it across the membrane,
Because primary active transport adds phosphates to protein what is it termed?
phosphorylation
How does the sodium potassium pump work?
exchange pump. pushes one ion out of the cell and the other ion in the cell both against the gradient
How many Na+ ions are pumped out and how many K+ ions are pumped in?
3 Na+ pumped out
2 K+ pumped in
Does the sodium potassium pump require energy?
yes 1 ATP per pump
The sodium potassium pump mains what?
an electrochemical gradient which is a electrical charge difference across plasma membrane
Voltage differences in the membrane is called what? what is it called when it’s at rest?
membrane potential
resting membrane potential
Resting membrane potential is what?
-70 mv
Vesicular transport uses vesicles which are what?
membrane-bounded sac filled with materials
Does vesicular transport require energy?
yes
What is exocytosis?
- vesicle fuses with membrane
• releases substances outside the cel
What is endocytosis?
- vesicle encloses material outside cell
• fuses with membrane to release inside cell
Exocytosis is good for what?
to move large substances outside the cell
Endocytosis is used for what three things?
- Used for the uptake of materials for digestion
– Used for retrieval of membrane from exocytosis
– Used for regulating membrane protein composition
What are the three types of endocytosis?
phagocytosis, pinocytosis, and receptor-mediated endocytosis
What is the inward fold of a membrane to form a pocket during endocytosis called?
invagination
What is phagocytosis?
engulfing of large particles
- uses pseudopodia
- lysosome fuse with vesicle and release digestive enzymes
- EX: marcrophage
What are the membrane bound organelles?
ER, Golgi apparatus, lysosome, peroxisomes, mitochondria
Where is the point of insertion for enzymes located?
the ER
The rough ER is for what? how ribosomes transported out?
protein production by ribosomes
- transported out by transport vesicles, shuttles proteins from rough ER to golgi apparatus
What are some functions of the smooth er?
synthesis, transport, and storage of lipids
• carbohydrate metabolism
• detoxification of drugs, alcohols, and poisons
Where is plentiful smooth ER?
cells of the testes to produce testosterone
- cells of the liver
What is the function of golgi apparatus?
packaging and storing
What does lysosomes do?
digestive enzymes
What does mitochondria do?
- digestion of fuel molecules to synthesize ATP
- termed POWERHOUSES
- Increase through fusion
What does ribosomes contain?
- Contain protein and ribonucleic acid
Where are ribosomes made and where are they assembled?
– Made within nucleolus and assembled in cytoplasm
The cytoskeleton plays a role in what 4 things?
- intracellular support
- organization of organelles
- cell division
- movement of materials
The cytoskeleton includes what things?
microfilaments, intermediate filaments, microtubules. actin
Cilia is found where?
lining portions of the respiratory tract
Flagella help with what? where is it found in humans?
movement, found only in sperm cell
Microvilli increases what? what is it supported by?
surface area, supported by microfilaments
The nucleus is the cell’s what?
control center
The nucleolus is made up of what? what does it produce?
proteins and RNA
- produces ribosomes
The nucleus has a double what?
phospholipid membrane
What is gap junction?
allows material to go cell to cell directly
*tunnel
What is tight junction?
Materials cannot move between cells force to move through the cell
What is desmosomes?
stronger bonds for places with stress
- ex: skin
DNA is coiled around what? what do these prduce?
histones they produce nucleosomes
If not coiled DNA is called what?
chromatin
If coiled DNA is called what?
chromosomes
What is the center of chromosomes called?
centromere
What are the funcitonal organization of DNA?
genes
DNA is?
segmental units of nucleotides
What does DNA provide instruction for?
synthesis of specific proteins
DNA has what two regions?
start & stop
What is the enzyme that assembles ribonucleotides?
RNA polymerase
What is the start of the DNA region called?
promoter (AUG, MET)
What is the end of DNA region called?
Terminator region, 3 possible codons
What are the 3 types of RNA used during transcription?
- mRNA
- tRNA
- rRNA
What is mRNA?
mesenger RNA
- brings DNA from template
What’s tRNA?
transfer RNA
- brings amino acids to the ribosome for assembly
What’s rRNA?
ribosomal RNA
- used to build ribosomes
What’s transcription? where does it occur?
mRNA brings recipe to the ribosome, occurs in the nucleus
Whats translation?
the language of DNA is translated into the language of proteins
How does translation work?
the genetic code (nucleotides) are combined into sets of 3 (codons) and translated into chains of amino acids (the building block of proteins) they’re linked by peptide bonds and it COSTS 3 ATP each peptide bond formed
What are codons?
sets of 3 nucleotides used to form the recipe for proteins
How many combinations of codons are possible?
64
The amino acid cysteine is responsible fo rwhat?
for disulphide bonds, the most powerful bonds found in proteins
What is cell division called?
mitosis
What does cell division begin with and end with?
1 diploid cell —> 2 identical daughter cells
What is a diploid cell?
cells that have chromosomes in homologous pairs
What is a homologous pair?
chromosomes have genes for the same train at the same location
What are the 5 phases of mitosis?
Interphase, prophase, metaphase, anaphase, telophase
What are the three steps of interphase?
o 1. Regular Cell function
o 2. DNA is uncoiled into chromatin
o 3. DNA replicated
What are the three steps of prophase?
o 1. DNA re-coils into chromosomes
One pair of sister chromatids per chromosome
o 2. Nuclear envelope dissolves
o 3. Spindle fibers form at the poles
What are the three steps of metaphase?
o 1. Chromosomes align at equator
o 2. Spindle fibers attach to each chromatid
o 3. Centromeres replicate
What are the three steps of anaphase?
o 1. Chromatids separated
o 2. Chromosomes toward poles
o 3. Cell temporarily tetraploid (4 pairs homologous pairs)
- double chromosome from the begining!
What are the three steps of telophase?
o 1. Chromosomes arrive at poles
o 2. Nuclear envelope re-forms
o 3. Cytokinesis occurs (cell splits)
- division of cytoplasm
What are tissues?
o Group of similar cells working together for perform a similar function
How many types of epithelial are there?
4 types
What are the 4 types of epithelial tissue?
epithelium, connective, nervous, muscular
Epithelial does what 3 things?
• “lines, covers, protects”
How would you describe epithelium tissue? what are the cells held together by? is there a lot of extraculluar matrix? describe the vessels…
o Layers of closely packed cells
Held together by tight junctions
Little or no extracellular matrix (stuff outside the cell)
Avascular (no blood vessels)
Epithelial forms a majority of what?
glads
In the tissue structure the polarity has what two types of surfaces?
apical (free surface), basal surface
Where could you find the apical surface?
• Exposed to the external environment or internal body cavity
Where would you find the basal surface
• Attached to a ‘basement membrane’ of connective tissue
The basement membrane is composed of what? describe the vessels?
Collagen fibers, carbohydrates, & proteins
Avascular
Epithelium tissue features what?
Extensive Innervation
What is Extensive Innervation?
o Touch, pressure, temperature, pain
What is the specialized epithelum called that detect the senses? name the senses it detects?
neuroepithelium
- Sight, taste, smell, hearing, equilibrium
How does epithelium regenerate?
High Regenerative Capacity (heals quickly)
What type of barrier does epithelium provide?
Physical Protection
What does the epithelium protect from?
dehydration, abrasion, destruction
Is epithelium selectively permeable or permeable to all things?
selectively permeable
How is epithelium named?
by the layers, and the cell shape
What does simple epithelial tissue do?
Filtration, absorption, secretion
Where is stratified epithelial tissue found?
Mechanically stressed areas (friction)
How does epithelial tissue regenerates?
Basal layer continually replaces apical layer
Simple squamous is found where?
• Lungs, blood & lymph vessels
SImple squamous within blood vessels is called what?
endothelium
Simple cubodial is found in what two places?
- Secretory region of glands
* Ducts of exocrine glands
SImple columnar often have what structure in it?
goblet cells
Goblet cells do what?
Unicellular gland
Secretes Mucin (+water = mucous)
What do goblet cells secrete and is it mulitcellular or unicellular?
Unicellular gland
Secretes Mucin (+water = mucous)
Non- ciliated has a “brush border” what is the structure that makes it appear that way?
microvilli
What does ciliated simple colomnar do? where is it found?
o Move mucous
o Found in respiratory tract (small tubes)
Ciliated pseudostratified columnar is found where?
o Found in respiratory tract (large tubes)
Non- ciliated simple columnar lack what two structures? where is it commonly found?
o Lack goblet cells & cilia
o Urethra & epididymis
In STRATIFIED squamous the basement layer is made of us what usually and the apical layer is made up f what?
• Basal layer = cuboidal, Apical layer = squamous
Keratinized stratified squamous has the apical layer what? where is it commonly found?
o Apical layer dead o Epidermous (top layer of skin)
Non-keratinized stratified squamous is what to the surface? where is it commonly found? how is the top layers kept moist?
o Alive to surface
o Top layers kept moist by secretions
o Mouth, Esophagus, Vagina
Glands can be categorized as what two things?
endocrine and exocrine
Describe Endocride glands..what things are usually endocrine glands? think systems DUH
o No ducts
o Hormones
Exocrine glads secrete where? describe them…
(secrete outside)
o Ducts
