biology final (this is for honors in highschool)

you only have 2 days to study

What types of cells go through mitosis?

Somatic/body cells

What type of sexual reproduction is mitosis? (Sexual or Asexual)

Asexual

During which phase of mitosis do the chromosomes line up along the middle(equator) of the dividing cell?

Metaphase

List the phases of mitosis in order.

prophase, metaphase, anaphase, telophase

If an organism’s diploid number is 50, it’s haploid number is?

25

what type of reproduction is meiosis?

sexual

Define zygote

a diploid cell resuting from the fusion of two haploid gametes.

Define gamete

a mature haploid male or female germ cell which is able to unite with another of the opposite sex in sexual reproduction to form a zygote.

Explain crossing over and what it leads to.

Crossing over is the process during meiosis where homologous chromosomes exchange portions of their chromatids, which leads to genetic variation.

mitosis produces _____ cells. Meiosis produces ____ cells.

diploid, haploid

How many daughter cells are produced in mitosis? Meiosis?

2, 4

Which type of cell division produces genetically different daughter cells?

Meiosis

Name the sugar that is found in DNA? RNA?

Deoxyribose, ribose

Wrtie the complementary DNA strand for ATCGCG

TAGCGC

List the 3 main differences between DNA and RNA

DNA is double-stranded, contains deoxyribose, and has thymine, while RNA is single-stranded, contains ribose, and has uracil.

List the 3 types of RNA and their functions

mRNA , tRNA , and rRNA. mRNA carries genetic information, tRNA transports amino acids, and rRNA forms the core of ribosome's structure.

Name the two steps of protein synthesis

Transcription and Translation

Where does transcription occur in the cell?

Transcription occurs in the nucleus of eukaryotic cells and in the cytoplasm of prokaryotic cells.

What is produced during transcription?

mRNA

How many bases are needed to specify one codon?

3

How many amino acids exist?

20

How many RNA codons are there?

64

If there are 5 amino acids in a polypeptide chain, how many bases would specify this?

15

Where does translation occur in a cell?

ribosome

What happens in translation?

mRNA is used to link amino acids forming a polypeptide chain. The tRNA transports and translates the correct amino acids.

What determines which amino acid will be added to the growing polypeptide chain?

mRNA

Gnes contain instructions that make a ______.

protein

If the anticodon reads AAC, what would the codon read?

UUG

Given the following DNA sequence: CCT GAT, transcribe (mRNA) and translate (tRNA).

GGA CUA; CCU GAU

What is a mutation?

a change in the DNA sequence.

If the second C in the DNA sequence CCT GAT were replaced with an A, transcribe (mRNA) and translate (tRNA). Would the protein change? What type of mutation occured?

GUA CUA, CAU GAU, yes, Substitution

Define dominant and write an example using the letter T.

An allele that always expresses its trait when present even when a recessive allele is present. ex Tt = Tall (notice how its still tall even when the the short allele is present).

Define recessive and write an example using the letter T.

The weaker allele that will only appear if no dominant allele is present.

Define homozygous and write an example using the letter T.

Two alike alleles, ex. TT or tt

Define heterozygous and write an example using the letter T.

Having two different alleles, ex. Tt

Define purebred and write an example using the letter T.

having only one type of allele (same as homozygous) ex. TT or tt

Define Hybrid and write an example using the letter T.

Having a mix of alleles (same as heterozygous) es. Tt

Define genotype and write an example using the letter T.

The genetic makeup of an organism. ex. TT, Tt or tt

Define phenotype and write an example.

The physical characteristic(s) of an organism, ex. tall, short

Define alleles and list the alleles for height of pea plants.

One of a number of different forms of a gene. Tall allele: T

Short allele: t

Write the genotype of a heterozygous red-flowered short pea plant.

Rrtt

How could two parent who have a dominant trait have a recessive child?

If they are both heterozygous for the trait, there is a ¼ chance of the child being recessive.

Phenotypic ratio for monohybrid cross and dihybrid cross.

3:1, 9:3:3:1

Define an autosome.

Any non-sex chromosome

What is a karyotype?

Visual representation of all chromosomes to be viewed as pairs.

How many chromosomes are shown in a normal human karyotype?

46

How many autosomes are shown in a normal human karyotype?

44

How many sex chromosomes are shown in a normal human karyotype?

2

what does a pedigree show you?

The history of a gene or medical condition across multiple generations of a family.

symbols for a male and female

male: square (filled in or hollow)

female: circle (filled in or hollow)

How would you determine whether a pedigree is dominant or recessive?

Whether the trait shows up in every generation or not.

If an individual has the disease, how will this be depicted in the pedigree?

filled in square for a male

filled in circle for a female

Genotype for a male and female

Male: xy

Female: xx

What is a sex linked trait?

A characteristic determined by a gene located on the X chromosome.

why are sex linked more common in males?

if they have the allele it will always be expressed no matter what

are sex-linked traits dominant or recessive?

recessive

List the 3 human sex-linked traits discussed in class.

colorblindness, muscular dystrophy, hemophilia

Define evolution

change over time; the process by which modern organisms have descended from ancient organisms.

Define adaptation and give an example.

heritable characteristic that increases an organisms’ ability to survive and reproduce in an environment. ex long giraffe necks

Adaptation can be ____ or _____.

physical, behavioral

Name the islands where Darwin found the most evidence for evolution.

Galapagos Islands

What is responsible for most changes in alleles within a population?

Mutations

Define gene pool.

Combined genetic info within a population.

Evolution acts on ____.

populations

natural selection acts on _____, not _____.

phenotypes, genes

what three conditions must be present for natural selection to occur?

inheritance

variation

competition

the three types of selection

Directional, stabilizing, disruptive

in genetic drift why do allele frequencies change?

due to random chance events

genetic drift impacts what size population

small population

define genetic equilibrium / Hardy-Weinberg principle

no change in allele frequencies.