Final Exam Flashcards
What is cohesion?
The attraction between molecules of the same substance
What is adhesion?
The attraction of molecules of two different substances
What are polar covalent bonds?
Chemical bonds formed from unequal electron sharing, resulting in a molecule with a partial charge.
What is an example of cohesion?
Xylem in a plant carrying up the water from the roots.
What is surface tension?
The cohesive force at the surface of a liquid.
What is the specific heat capacity?
The measure of how much heat needs to absorbed or given off in order to change the temperature.
What is a solvent?
The substance that dissolves a solute.
What is an aqueous solution?
A solution in which water is the solvent.
What is deuterium?
A stable isotope of hydrogen that contains only one neutron.
What is transpiration?
The movement of water within a plant and its evaporation from its aerial parts.
What is included in a Nucleotide?
A phosphate group, a pentose sugar, and a nitrogenous base.
If there are 345 nucleotides… how many molecules of water are released?
344
What is the 5’ end of a nucleotide and the 3’? From which direction are DNA strands synthesized?
5’ end - unbound phosphate group
3- end - ends at deoxyribose sugar
Strands are synthesized from direction 5’ to 3’.
What is replication, transcription, and translation?
Replication - DNA polymerases makes a copy of DNA
Transcription - RNA polymerase makes an RNA copy of DNA base sequence.
Translation - RNA base sequence determines the amino acid sequence of a polypeptide.
Nucleosomes are made of what?
DNA wrapped around 8 histones and 1 histone to condense it.
What are lipids?
oils at warmer temperatures and fats at cooler temperatures.
What are the monomers of triglyceride lipids?
Glycerol and fatty acids
What are monosaccharides?
The monomers of carbohydrates, Ex. ribose, glucose, galactose.
What are the 4 biochemical groups that all contain Carbon?
Lipids, proteins, nucleic Acids, and carbohydrates.
What is the general form of carbohydrates?
CnH2nOn
What is hydrolysis?
water molecule is used to split up into two components and makes two new molecules.
Describe glucose
- produced in photosynthesis
- used to make cellulose (structural) and starch (energy)
- plants use two bonds, alpha 1-4 linkages and 1-6 linkages (refers to the bonded carbon atoms)
- amylose: long chains of alpha glucose
- amylopectin: long chains of alpha glucose with branching chains
What determines ABO blood types?
Glycoproteins use A and B antigens to produce blood types.
What are purine bases and what are pyrimidine bases?
Purine - adenine and guanine with two rings of atoms
Pyrimidine - cytosine and thymine with one ring of atoms
What is the regular equation for a triglyceride?
1 glycerol + 3 fatty acids = 1 triglyceride + 3 water molecules
What is adipose tissue?
cells that store fat in the form of triglycerides.
What are phospholipids made up of?
a polar group, phosphate, glycerol, and two fatty acid tails. The head is hydrophilic while the tails are hydrophobic.
What are steroids?
groups of hormones made from the lipid cholesterol - 4 connected ring structure.
What parts does an amino acid have?
an amine group, a central carbon (with hydrogen), a R group, and a carboxyl group.
How many essential and non essential acids are there?
11 non-essential acids and 9 essential acids that need to come from our food.
What is protein denaturation?
The configuration change of a protein resulting in a loss of function due to extreme ph or temperature changes.
What are the three types of ionic bonds?
- covalent bonds such as disulfide bonds
- hydrogen bonds
- hydrophobic / hydrophilic interactions
What is a conjugated protein and what is an example?
A protein attached to a non-polypeptide group known as a prosthetic group. Ex. Haemoglobin.
What is the difference between insulin and collagen?
Insulin:
- globular protein
- soluble
- spherical
Collagen
- fibrous protein
- long / narrow
- insoluble
Both are examples of non-conjugated proteins.
Why aren’t viruses considered to be alive?
They do not carry out metabolism, homeostasis, and do not respond to external stimuli.
What did the miller-urey experiment prove?
It proved how some amino acids can be spontaneously produced.
Why is the miller-urey experiment not an answer for all life on Earth?
It didn’t account for all conditions of prebiotic Earth and didn’t produce all organic molecules.
What do fatty acids do when mixed with water?
Create spontaneous vesicles
Why was RNA considered the first genetic material?
It can store genetic material, it is capable of self-replication, and can catalyse reactions.
What is the evidence for LUCA?
Most recent common ancestor for all organisms on Earth and no fossil remains. LUCA may have evolved near hydrothermal vents that are rich in organic compounds and fossils of cyanobacteria have been found on the ancient seafloor.
What is the formula for magnification?
Magnification = measured length / actual length
how many nm are in one mm?
1 000 000
What are some of the differences between light microscopes and electron microscopes?
Light microscopes:
- easy
- cheap
- resolution is max 200nm
Electron microscopes:
- hard to use
- max resolution is 2000x better
- expensive
- relies on electrons
What are some of the features of prokaryotic cells?
Cell wall, cytoplasm, plasma membrane, 70s ribosomes, nucleoid region, flagellum, pillus
What is the difference between rough ER and smooth ER?
Rough ER has ribosomes on its surface, and is the site of protein synthesis. Smooth ER has no ribosomes and is involved in lipid synthesis and detoxification.
What does the GA do?
It modifies and packages proteins.
What are some examples of atypical cell structures?
Aseptate Fungal Hyphae - multinucleate
Skeletal Muscle Cells - multinucleate
Red Blood Cells - no nucleus
Phloem Sieve Tube Elements - no nucleus
What is the endosymbiotic theory?
Suggest that all eukaryotes evolved from a common unicellular ancestor that had a nucleus and reproduced.
What is simple diffusion?
Movement of particles from a region of high concentration to an area of low concentration passively. Ex. oxygen moving from alveoli to the bloodstream.
What are integral proteins?
Proteins that are permanently attached to the plasma membrane and penetrate in to the centre of the phospholipid bilayer. They can be transmembrane or partially penetrate the bilayer.
What are peripheral proteins?
Proteins that are temporarily attached to one side of the membrane, are hydrophilic, ex. receptors or enzymes.
What are aquaporins?
Integral channel proteins which selectively transport water through membranes. Example of facilitated diffusion.
What is active transport?
Movement of particles against the concentration gradient using protein pumps and ATP.
What are glycoproteins?
membrane proteins with a carbohydrate chain attached
What are glycolipids?
phospholipids with a carbohydrate chain attached
What is glycosylation?
Carbohydrate chains attaching to phospholipids and membrane proteins.
What are some of the functions of glycoproteins and glycolipids?
cell-to-cell communication, receptors, immune response, cell recognition, etc.
Which have higher melting points, unsaturated fatty acids or saturated?
Saturated since their tails are closer packed.
What is cholesterol located in a membrane and what is its function?
Located between fatty acid tails and regulates the fluidity of cell membranes.
What is the travel of proteins to outside of the cell?
Rough ER to Golgi Apparatus, to Plasma Membrane.
Of what and how much do sodium potassium pumps transport out?
3Na are transported out of the cell and 2K are transported into the cell.
What are examples of structures that are not considered organelles?
Cell membrane, Cytoskeleton, cytoplasm, cell wall.
What is ultracentrifugation?
The separating of organelles due to density.
What is phagocytosis?
The process by which solid materials (bacteria) are transported into the cell by Endocytosis.
What part of the mitochondria contains the enzymes needed for the Krebs cycle?
Matrix
The golgi apparatus is composed of flattened sacs called…
Cisternae
Totipotent stem cell?
Can differentiate into all other cell types or develop into an embryo
Morphogens, what are they?
Gene regulating chemicals released from embryo cells and diffuse through tissues.
What are some examples of stem cell niches?
Bone Marrow, hair follicles, etc.
Which of the following organelles are surrounded by a single membrane?
i) Ribosome
ii) Rough endoplasmic reticulum
iii) Chloroplast
iv) Lysosome
ii and iv
If you found a eukaryote cell in an electron microscope image, and it contained a lot of rER, Golgi apparatus and many darkly stained vesicles, what do you think the function of the cell is most likely to be?
- The storage of lipids.
- The production and transmission of a nerve impulse.
- The transport of oxygen in the blood.
- The production and secretion of a substance containing a protein.
- The production and secretion of a substance containing a protein.
Why is it that prokaryotes can divide by the simple process of binary fission, but eukaryotes have to divide by the more complex process of mitosis?
Binary fission and mitosis are the same thing.
Prokaryotes are smaller than eukaryotes.
Eukaryotes have mitochondria but prokaryotes do not.
Prokaryotes have only one chromosome whereas eukaryotes have multiple chromosomes
d)
The process of copying a gene’s DNA sequence into a sequence of RNA is called:
replication
PCR
translation
transcription
transcription
Which contains the genetic code?
aRNA
tRNA
rRNA
mRNA
mRNA
At which stage of meiosis are bivalents formed?
metaphase II
prophase I
prophase II
interphase
Prophase I
Which event happens in meiosis II but not in meiosis I ?
sister chromatids move to opposite poles
Spindle microtubules attach to centromeres
chromosomes become shorter and thicker by coiling
crossing over occurs
sister chromatids move to opposite poles
What is an operon?
A unit of DNA containing a cluster of genes under control of a promoter and a repressor
What is the role of an activator?
Enhances interaction between RNA polymerase and the promoter
In order for a gene to be transcribed, RNA polymerase must have access to the DNA helix and be able to bind to the genes __________
promoter
In the function of the lac operon in E. coli, the lac genes are transcribed in the presence of lactose because:
- the repressor cannot bind the the promoter
- RNA polymerase binds to the operator
- CAP does not bind to the operator
- lactose binds to the repressor
lactose binds to the repressor
How does genomic imprinting affect gene expression?
Increase expression of imprinted alleles
Lower expression of imprinted alleles
If the allele from the father is imprinted, then that will be the allele expressed.
If the allele from the mother is imprinted, then that will be the allele expressed
Lowers expression of imprinted alleles.
Which statement distinguishes between the roles of free and bound ribosomes?
Free ribsomes synthesize proteins for uses inside of the cell and bound ribosomes synthesizes proteins for uses outside of the cell.
What conveys messages from the central nervous system to an endocrine gland?
Hormones
What is the role of calcium ions in muscle contraction?
They unblock myosin binding sites on actin.
What are functions of female reproductive hormones?
Estrogen and progesterone promote the development of female reproductive organs in the embryo.
What occurs around day 15 of the cycle?
Formation of a corpus luteum.
What is a function of HCG?
To stimulate the corpus luteum to produce progesterone during early pregnancy.
What happens during inspiration?
Diaphragm contracts and moves down while the external intercoastal muscles contract and move the ribcage up and out. Pressure is decreased in the lungs.
What happens during expiration?
Abdominal muscles contract and push the diaphragm upwards. External intercoastal muscles relax and internal intercoastal muscles contract and push the ribcage down and inwards. Volume in the thorax decreases, increasing the pressure in the lungs.
What is the tidal volume and the vital capacity?
The tidal volume is the amount of air that moves in and out of the lungs in a normal breath. The vital capacity is the greatest volume of air that can be expelled by the deepest possible breath.
What is the difference between arteries and veins?
Arteries have a thick wall and narrow lumen while veins have a thin wall and wide lumen.
What is Atherosclerosis?
The harding and narrowing of the arteries due to the build of cholesterol, triglycerides, and other substances on walls.
