Honors Biology Final Exam Study Guide: Cell Cycle, Genetics, Evolution, and Ecology

What are somatic cells?

any cells in the body that are not reproductive cells

What are germ cells?

reproductive cells

How can you determine if an individual is male or female based on chromosomes?

(XX) is female, (XY) is male.

What are the steps of meiosis?

Meiosis I, which reduces the chromosome number by half, and Meiosis II, which separates the sister chromatids.

What are the products of meiosis I?

two haploid cells

What are the products of meiosis II?

four haploid cells

What are the three ways genetic diversity is achieved during meiosis?

independent assortment of chromosomes, crossing over during prophase I, and random fertilization.

How are chromosomes reduced during meiosis I?

homologous chromosomes are separated

How are chromosomes reduced during meiosis II?

sister chromatids are separated

How can you calculate the number of ways tetrads can line up on the equator?

using 2^n, where n is the number of homologous chromosome pairs.

What is the haploid number of chromosomes in humans?

23

What is the diploid number of chromosomes in humans?

46

What are Mendel's laws?

Law of Segregation and the Law of Independent Assortment

What is the difference between genotype and phenotype?

Genotype is the genetic makeup of an organism, and phenotype is the observable trait

What is heterozygous?

Tt

What is homozygous?

TT ot tt

What is a purebred?

an organism that has been bred from parents with the same traits, resulting in a homozygous genotype.

What is a hybrid?

the offspring of two different varieties or species, typically heterozygous for the traits in question.

What is a sex-linked trait?

a trait associated with a gene located on a sex chromosome

What are Punnett squares used for?

showing the possible genotypes of offspring.

What is the structure of proteins?

amino acids linked by peptide bonds, creates complex structures

What is an enzyme?

speeds up chemical reactions in the body

What is the monomer of DNA?

a nucleotide

What is the monomer of RNA?

a nucleotide

What are the major differences between DNA and RNA?

DNA is double-stranded, while RNA is single-stranded

What is a codon?

a sequence of three nucleotides

how many amino acids are there per codon?

a codon codes for one amino acid.

What occurs just prior to mRNA leaving the nucleus?

mRNA undergoes processing, which includes capping, polyadenylation, and splicing.

What occurs during transcription?

DNA is used as a template to synthesize mRNA, this occurs in the nucleus.

What occurs during translation?

mRNA is read by ribosomes to synthesize proteins, occurring in the cytoplasm.

What is a mutation?

a change in the DNA sequence that can lead to changes in protein structure and function.

What are the three types of RNA?

mRNA tRNA rRNA

What are the base pairing rules?

a-t g-c

What is Darwin's theory of evolution based on?

the concept of natural selection

What is artificial selection?

the process by which humans breed plants and animals for specific traits

What is natural selection?

the process where organisms better adapted to their environment tend to survive and produce more offspring.

What are the five evidences of evolution?

fossil records, comparative anatomy, molecular biology, biogeography, and embryology.

What are vestigial structures?

body parts that have lost their original function through evolution, such as the human tailbone.

What are analogous structures?

body parts that serve similar functions but evolved independently, such as wings of birds and insects.

What are homologous structures?

body parts that share a common ancestry

What is gene flow?

the transfer of genetic material between populations, which increases genetic diversity.

What is genetic drift?

The change in allele frequencies in a population (ex, bottleneck effect and founder effect)

What is intersexual selection?

a form of sexual selection where individuals of one sex choose mates based on certain traits.

What is intrasexual selection?

a form of sexual selection where individuals compete for mates.

What are reproductive barriers?

mechanisms that prevent species from interbreeding, leading to speciation.

What is divergent evolution?

when related species become less similar over time

What is convergent evolution?

when unrelated species develop similar traits due to similar environments

What is altruism in biology?

behaviors that benefit other individuals at a cost to its self

What are the levels of ecology?

individual, population, community, ecosystem, biome, biosphere.

What is the equation for population density?

the number of individuals divided by the area they occupy

What is logistic growth?

When populations grow rapidly at first, and then level off as resources become limited.

What is exponential growth?

when population size increases rapidly without any limits.

What are biotic factors?

living components of an ecosystem

What are abiotic factors?

non-living components of an ecosystem

What is carrying capacity?

The maximum number of individuals of a species that an environmentc can support.

What are limiting factors?

environmental conditions that restrict the growth

What are the two types of limiting factors?

density-dependent factors and density-independent factors

What is the relationship between carrying capacity and limiting factors?

Limiting factors determine the carrying capacity of an environment by affecting the resources available for a population.

What are the types of symbiotic relationships?

mutualism (both benefit), commensalism (one benefits, one is unaffected), and parasitism (one benefits at the expense of the other).

How do disturbances impact a community?

disrupts community structure, leading to changes in species composition and ecosystem dynamics.

How do humans impact the environment?

through activities such as pollution, habitat destruction, and the introduction of invasive species.