Midterm Flashcards
How many chromosomes are in a “normal” human karyotype
46
What’s produced during transcription?
Transcription is the process of making a strand of MRNA from a gene on a DNA molecule. (Occurs in nucleus)
Base pair rules…?
A=T
C=G
(For RNA, A=U)
What can a karyotype show?
Extra or missing chromosomes, and the gender (large changes)
(XY or XX)
What are the sex chromosomes of a male?
Female? Male = XY, female = XX
What is the gene pool?
Hypothetical spot where all genes for a trait in a
population are.
What sex chromosomes does a mother give to her child?
Mother can only give an X chromosome
What is phenotype?
The physical characteristic that an organism has due to genes. Ex. Red flower
How would Down syndrome be detected on a karyotype?
Extra chromosome (triosmy) #21
What’s the difference between a point mutation and a chromosomal mutation?
Point mutation only affects one nucleotide in a sequence of DNA. A chromosomal mutation is when there is an extra (trisomy) or missing (monosomy) due to non-disjunction (failure of chromosomes to separate during meiosis)
Most sex linked genes are located where?
On the X chromosome
Why is colorblindness more common in males than in females?
Since males are XY and only have one X chromosome, they only need to have one affected allele
to have the trait. Since females have two X’s, they will need to have both alleles
to have said trait.
What is “DNA Fingerprinting” and what is it based on? Also called gel electrophoresis.
It’s based on the idea that no two people (except identical twins) have the same
DNA; so no two people will have the same DNA “fingerprint”.
What restriction enzymes and what do they do?
Restriction enzymes are used in
DNA fingerprinting. They cut strands of DNA at a particular sequence that they
recognize.
The 2 main sources of genetic variation are?
Mutations and sex
What is genotype?
The alleles (portions of a gene) of an individual. Ex. Rr
What is gel electrophoresis and what can it be used to determine?
It can be used to determine who committed a crime, paternity tests, if organisms’ DNA is similar (relatedness), to check for a certain gene on a strand of DNA, etc.
What is haploid and diploid?
Haploid is one copy of each chromosome (n), diploid is two of each chromosome (2n)
What are codominance, incomplete dominance, and polygenic traits?
Codominance = both traits are expressed (ex. Red and white speckled flower) Incomplete dominance = heterozygous is in between both homozygous traits (RR = red, Rr is pink, and rr is white)
What is a pedigree and what can it be used for?
Can be used to tell how a trait is inherited, what people have a trait, etc.
What is homozygous dominant, homozygous recessive, and heterozygous?
RR, rr, Rr
What are the similarities and differences between DNA and RNA
Similarities = both have phosphate and bases cytosine, guanine, and adenine Differences = DNA has sugar deoxyribose/ RNA has sugar ribose, DNA is double
stranded/ RNA is single stranded, DNA has thymine/RNA has
uracil
What is the difference between a dominant and recessive allele?
Dominant is usually expressed more than recessive and is written with a capital letter and recessive is written lowercase.
What book did Darwin write?
On the Origin of Species (by Means of Natural Selection)
What is the advantage of a polygenic trait over a single gene trait?
Polygenic
trait results in higher variation in a population. This will give the population a
better chance of survival if adverse conditions develop in the environment.
What sex chromosomes does a father give to his child?
Male has a 50% chance of making sperm that contain an X chromosome, 50% for a Y sperm. All females’ eggs will contain one X chromosome.
What are the components of the DNA molecule?
Deoxyribose, phosphates,
nitrogen bases
A hypothesis is useful only if it can be ____________.
tested
Genes contain instructions for assembling what?
Proteins
How many variables are tested in an experiment?
one
What kingdoms contain organisms with cell walls?
Plantae, Eubacteria,
Archaebacteria, Fungi
Why does diffusion occur?
Because molecules are always in motion. Move from high concentration to low concentration.
What is homeostasis?
A balance
What is metabolism?
Breakdown of materials in the cell/body
What are the monomers of proteins?
What are the main functions of proteins?
Amino acids; proteins fight infections, speed up reactions, build and repair
tissues, move things, etc.
What are the monomers of lipids? What are the main functions of lipids?
Glycerol and fatty acids; lipids are used for energy storage
What has to separate during DNA replication?
Two strands of DNA molecules;
hydrogen bonds are broken
What are the monomers of carbohydrates? What are the main functions of carbohydrates?
Monosaccharides; main source of energy
What are the monomers of nucleic acids? What are the main functions of nucleic acids?
Nucleotides; store and transmit heredity
What is the ATP molecule made of?
Adenine,Ribose, and 3 Phosphate Groups
What is the equation of photosynthesis? Know the reactants and product
6H2O + 6CO2 (reactant) yields C6H12O6 + 6O2 (products)
What is the equation of cellular respiration? Know the reactants and products
Opposite of photosynthesis
What are pigments? What is the main pigment in most plants?
Light absorbing
molecules. Chlorophyll.
There are 2 major categories of cells. What are these categories based on?
Prokaryotes/Eukaryotes. Whether or not they have a nucleus. Pro = No, Eu =
Do
Who were Robert Hooke, Leeuwenhoek, Schleiden, Schwann, and Virchow?
Hooke= looked at cork under first microscope
Leewenhoek = looked at living single-celled microorganisms )”animalcules” under improved microscope. First to look at living stuff.
Schleiden, Schwann, Virchow = made cell theory
What is osmosis?
Diffusion of water
In DNA, what determines the traits of an organism?
The order of nitrogen bases
Understand how many ATP molecules get made in glycolysis and in total with O2
Glycolysis = 2 ATP, Cellular respiration (with O2) = 36 ATP
Why do plants appear green?
They reflect (don’t absorb) green light
In what organelle does cellular respiration take place?
Mitochondria
What are the levels of organization from atom to biosphere?
Atom, molecule, cell, tissue, organ, organ system, organisms, population, community, ecosystem, biosphere
What is the difference between an autotroph and a heterotroph?
Autotroph makes its own food, heterotrophs must eat other things to survive
What is the difference between aerobic and anaerobic?
Aerobic = with oxygen,
anaerobic = without
What causes your muscles to burn?
Build up of lactic acid
What is the difference in the products of mitosis and meiosis?
Mitosis = 2 identical, diploid cells. Only occurs in somatic cells.
Meiosis = 4 genetically different haploid cells. Occurs in gametes.
What is a codon and an anticodon?
Codon is on the mRNA strand. It is three letters; each codes for an amino acid. Anti-codon is on the tRNA strand. It’s job is to bind to the correct codon to ensure proper amino acids are brought to the ribosome.
What are the 3 types of RNA and what do they look like?
See diagrams
What are the steps of Mitosis? Know what each step looks like.
PMAT!! No interphase or cytokinesis!
What is the difference between a polymer and a monomer?
Many monomers make up a polymer. A monomer are the “pieces” of a larger molecule. Ex. Amino acid is a monomer for a protein (polypeptide)
What are centrioles and what is their role in mitosis and meiosis?
They are responsible for ensuring spindle fibers are formed and ensuring things are in the right spot during mitosis/meiosis
What is the process of DNA replication
DNA is unwound/unzipped by DNA helicase, each half of DNA serves as a template for new strand to be build, DNA polymerase brings in new nucleotides to build new strand. Each new DNA molecule contains one old strand and one new strand.
What is produced during DNA replication?
2 identical strands of DNA
Why must cells divide?
Volume increases faster than surface area. Cell builds
up too much waste and needs too much food/O2 than can go out/in. Too much
demand on DNA
What is the same in every cell in the body?
Cytoplasm, cell membrane
What is cell specialization? Give examples in your body.
Occurs in
multicellular organisms where each cell has a special job. Ex. Red blood cells
carry oxygen and nerve cells transmit impulses
