Transcription, Karyotypes, and DNA Processes Flashcards

Flashcards based on lecture notes about transcription, karyotypes, RNA and protein synthesis, DNA replication, mitosis, and related terminology.

What is the state of each long DNA molecule in our nucleus before duplication?

An unduplicated chromosome

What must happen to DNA before a gene can be copied?

It unwinds and unzips.

What enzyme is responsible for making RNA?

RNA Polymerase

Where does RNA polymerase start copying DNA?

At the promoter region on the DNA

In transcription, where is the gene located?

On the template strand

What does RNA Polymerase use to add RNA nucleotides?

Base pairing rules

Where does RNA Polymerase stop copying?

At a termination signal

Where does the RNA go after transcription is complete?

To the cytoplasm or ribosome

What does 'transcribe' mean?

To copy information

What is a transcript?

A written or typed version of spoken words

What is a gene?

A section of DNA that codes for a protein

What happens to the DNA after transcription?

It rewinds back into a double helix.

What type of cell is Karyotype A from, given it has pairs of chromosomes?

Diploid cell

What type of cell is Karyotype A from?

A body cell

What type of cell is Karyotype B from given it has only one of each chromosome (1n)?

Haploid cell

What type of cell is Karyotype B from?

A reproductive cell

How many copies of each chromosome do human body cells have?

Two copies

Where do the two copies of each chromosome in human body cells come from?

One parent each

What can having more than one copy of a gene protect against?

Mutations

What can too many or too few chromosomes cause?

Genetic disorders

What do homologous chromosomes have in common?

The same genes in the same order

What might differ between homologous chromosomes?

Versions (alleles) of the genes

What type of chromosome issues doctors use karyotypes to look for?

Missing chromosomes, Extra chromosomes, Structural changes

What does inheriting at least one dominant allele result in?

A dominant trait

What does inheriting two recessive alleles result in?

A recessive trait.

What genotype do people with blue eyes have?

bb

Define transcription.

The process of making RNA.

Which enzyme makes RNA?

RNA Polymerase

List three differences between RNA and DNA.

RNA has uracil instead of thymine; RNA is single-stranded; RNA uses ribose sugar

What do genes code for?

Proteins

What are proteins made of?

Amino acids

What organelle makes proteins?

Ribosomes

What is a codon?

A three-letter RNA sequence that codes for an amino acid

If DNA is ATG, what is the corresponding RNA?

UAC

What happens when a stop codon is read?

Translation ends, and the protein is released.

Where do plants get carbon, hydrogen, and oxygen to build glucose?

Photosynthesis

What two nutrients (elements) do plants need to add to glucose to make it into a nucleotide?

Nitrogen and phosphorus

Where do plants get Nitrogen and Phosphorous?

Soil

What is the shape of a DNA molecule AND why is it called that?

Double helix because it is 2 strands in a spiral

What does DNA polymerase do?

Builds new DNA strands by adding complementary nucleotides to the template strand. It also proofreads to correct errors.

What does Helicase do?

Unzips the DNA double helix by breaking hydrogen bonds between base pairs, creating two single strands for replication.

What does Ligase do?

Seals gaps between DNA fragments (Okazaki fragments) on the lagging strand, creating a continuous strand.

List the steps of DNA Replication

Unwinding the DNA, Priming the Strands, Building the New DNA Strands, Sealing the Gaps, Proofreading and Completion

In a ladder model of DNA what do the steps of the ladder represent?

What part of the nucleotides is the step

Why is DNA replication said to be semi-conservative?

"Semi" means half, and "conservative" means to preserve

Each DNA molecule in an replicated chromosome is identical to the other, so what do we call them?

Sister chromatid

What is it called when parallel lines go in opposite directions?

Antiparallel

What are all of the possible outcomes of a mutation?

Stays the same, changes, or kills you

Why did we use glue and solid lines to represent covalent bonds in our paper DNA model?

Because they are strong

Why did we use paperclips for H-bonds?

Because they are weak

Why do we call interphase INTERphase?

The prefix "inter-" means "between", and interphase is the stage between two mitotic phases.

What is the cell doing at that time (during interphase)?

preparing for cell division

Why can you NOT see individual thread-like chromatids at this time?

The DNA is loosely coiled in a structure called chromatin.

What do you call this long thin form of chromosomes?

Chromatin

List the phases of mitosis in correct order

Prophase Metaphase Anaphase Telophase

What happens during prophase?

Chromatin condenses into visible, distinct chromosomes

What happens during metaphase?

The chromosomes line up along the metaphase plate

What happens during anaphase?

The sister chromatids are pulled apart toward opposite poles of the cell

What happens during telophase?

The chromosomes begin to decondense back into chromatin

Macromolecule

*4 types Very big molecule 1. Lipids-fat/oil 2. Protein (chain of amino acids) 3. Polysaccharide (chain of sugars) 4. Nucleic Acids (DNA/RNA)

Covalent Bonds

Very strong bonds (solid lines)

H-Bonds

Weak bonds (------) easy to break and reform (put back together)

Enzymes

*2 that make DNA Molecules that break or form covalent bonds *DNA Polymerase, Ligase

Chromosome

1 DNA molecule (double helix) and some proteins.

DNA Replication

Process to copy DNA

DNA replication is Semi-conservative because….

Each new molecule uses one of the original chains of nucleotides.

Helicase

Enzyme-untwists the helix -push 2 chains of nucleotides apart

Parental Strand

The original chains of nucleotides before DNA replication.

Daughter Strand

The new chains made by matching spare nucleotides to the parent strands

Centromere

Indented area in the center of a chromosome. -where identical DNA molecules are held together.

Sister chromatids

Identical DNA molecules made by replication.

Scientific Facts

Based on years worth of research/data in primary literature

Gene Mutations

Change in nucleotide order of only one gene.

Dominant Allele

Version of a gene that takes over and hides the recessive alleles (N__)

Recessive Allele

An allele that is hidden when a dominant allele is present. It only shows in the phenotype if both alleles are recessive (ex: bb).

Karyotype

A picture of all the chromosomes in a cell, arranged in pairs. Used to check for extra, missing, or abnormal chromosomes.

Homologous chromosome

A pair of chromosomes—one from each parent—that have the same genes in the same order, but may have different versions (alleles).

Diploid cells (2n)

Cells that have two copies of each chromosome. These are body cells like skin, muscle, and blood cells.

Haploid cells (1n)

Cells that have only one copy of each chromosome. These are sex cells (sperm and egg).

genotype

The genetic code an organism has for a trait (example: Bb, bb, or BB).

Phenotype

The physical trait that shows up (example: blue eyes, brown hair). It’s what the genotype makes happen.

Transcription

The process of copying DNA into RNA. Happens in the nucleus before making a protein.

macro-

Big

micro-

small

poly-

many

Mono- or uni-

One or single

di- or bi

Two or double

co

together/share

Sym or syn

together

-ine

Name of N-base (or nucleotide)

-ose

Name of a sugar

-ase

Name of an Enzyme

inter-

Between (interstate)

intra-

Within (inside)

cyto-

cell

plas-

Fluid

kine-

Motion

karyo-

Nucleus

Eu

with

homo

same