Zoology Final Exam

Characteristics of life

Characteristics of life

Cellular organizaiton

Heredity (reproduction

Growth, repair, and development

Metabolism

Homeostasis

Responding to environment

All animals have these traits

Multicellular, eukaryotic cells

Motility

Tissue structure

Nervous System/tissue

Sexual Reproduction

Formation of blastula during embryonic development

Classification levels

Domain

Kingdom

Phylum

Order

Family

Genus

Species

The 3 domains

Archaea

Bacteria

Eukaryota

The 7 Kingdoms

Archaebacteria, Eubacteria, protozoa, chromista, fungi, plantae, animalia

Prezygotic

Before fertilized egg; geographic isolation, temporal isolation

Postzygotic

After fertilized egg; sterile, low fitness

Species

A kind of organism that can breed with others of its kind and produce fertile offspring; they are reproductively isolated from other species that are similar

Geographic isolation

A population of species gets separated from another population of species and can no longer breed with one another

Behavioral isolation

Differences in courtship behaviors and other cues keep individuals of close relation from mating

Temporal isolation

When two populations reproduce at different times, so there is little chance they will breed with each other

Evidence of evolution

Fossils, Homologous structures, vestigial structures, Embryos, biochemicals

Fossils

Remains or traces of organisms from the past; Relative dating- no true fossil age but have an idea of it from rock layers; Absolute dating- radioactive dating based on amount of remaining radioactive isotopes

Homologous structures

Structures that are similar even if their function is not

Vestigial structures

Structures that seem to have no purpose today, but must have had one in an earlier ancestor long ago

Embryos

First resemble tadpoles and then develop following the general pattern of evolution; this could indicate all organisms had a common ancestor

Biochemicals

The amino acid order indicated by the hemoglobin is almost the same in closely related organisms

Genetic drift

Chance event that randomly removes or includes some individuals from the population. Those that remain reproduce on only those genes; quick and catastrophic event

Kinds of genetic drift

Bottleneck effect, founder effect, migration, natural selection, artificial selection

Bottleneck effect

reduction in population size

Founder effect

Subset of population finds new population

Migration

The regular movement of animals from one area to another

Requirements for successful migration

Physical endurance, mechanics for storing energy, food sources along route

Reasons for migration

Steady food supply, allows for reproduction

Results of migration

Helps equalize gene pool since it often combines multiple subgroups; increases gene diversity

Natural selection

Organisms which are best suited to he environment survive and reproduce to pass their gene composition to the next generation

Artificial selection

Humans choose which animals live or get to reproduce thus altering the outcome of offspring

Sexual selection

Mates of one sex compete with others for the attention of the opposite sex for the purpose of mating; traits used to increase the chance of mating may even make them more vulnerable to predation but the benefit outweighs the cost

Directional selection

The genotype/phenotype frequency changes overtime towards one extreme

Stabilizing selection

the environment selects against the extremes of a trait resulting in a fairly constant appearance of the trait over time

Disruptive selection

Organisms survive at either extreme but don’t have as much success with an inbetween trait

Coevolution

the evolution of two species in response to changes in same environment; may evolve to help benefit two species or make competition

Divergent evolution

Species sharing a common ancestor and becoming more and more different due to living in different environments

Convergent evolution

Distantly related organisms evolve to have similar features to adapt to similar environments

Extinction

The dying out of a species so that no more exist on earth; can occur when the environment changes faster than the genetic diversity and fitness of individuals can keep up with

Species can rapidly die because

Addition of new species

Pollution and climate change

Limited resources

Least Concern

Population members high

Near threatend

Declining population numbers

Vulnerable

Will be endangered if conditions do not change

Endangered

Species number is low; at serious risk

Critically endangered

Extremely high risk; less than 250 individuals

Mass extinction

Rapid events that wipe out the majority of life on Earth; if environmental change is great enough, fast enough, and on a global scale, the whole planet is in trouble; has happened about 5 times

Cladistics

Classification based on the order in which species descended over time with the assumption of a common ancestor

Cladogram

An evolutionary tree indicating how organisms are related to one another

Derived characteristics

traits that can be used to figure out evolutionary relationships among groups of species

Nodes

Each place where a branch splits in a cladogram

Clades

A group of organisms that share similar traits derived from a common ancestor

Molecular clocks

Using the mutation rate in DNA to determine evolutionary relatedness; closely related organisms tend to have DNA mutations at a similar rate

Mitochondria DNA (mtDNA)

Mutations at a rate of 10x that of nuclear DNA; passed from mom to child; easier to use when tracing back genes; helpful to determine relatedness in close species

Ribosomal RNA

Mutates at a very slow rate; useful for determining distant species

DNA Hybridization

Using melting point of hybridized DNA to Determine the number of hydrogen bonds between strands, this shows similarities between the two

Adaptation

Any trait that enhances the survival and reproduction of an organism

Isolating mechanisms

Factors that affect the gene pool of a population; can lead to the formation of a new species

Gene flow

Occurs when organisms from one community migrate into another; introduces new alleles to the population; can result in a change in the genetic makeup of a population

Fitness

The ability of an organism to survive and reproduce in its environment

DNA sequencing

Most reliable evidence supporting the theory of evolution

Diploid

Having a double set of chromosomes; allows for increased genetic variation among members in a population

Crossing over

Genetic diversity is partial due to this process during meiosis

Background extinction

the general number of extinctions that occur at any period in Earth’s history

What kind of evolution often follow a period of numerous extinctions?

Rapid Speciation or macroevolution

Dichadmais key

Can be used to identify an organism using choices between alternative characteristics

Types of organization

Symmetry, embryological development, body cavity development, tissue organization

Symmetry principal

More complex=less symmetrical

Asymmetric

arrangement of body parts without a central axis or point

Radial symmetry

arrangement of body parts such that a single plane passing through the oral-aboral axis divides that animal into mirror images

Bilateral symmetry

Arrangement of body parts such that a single plane passing through the longitudinal axis divides the animal into right and left mirror images

Cephalization

Form distinct head to analyze the environment as they move through it

Anterior

head end; end that meets environment first

Posterior

Tail end (back)

Dorsal

Back of animal; upper surface

Ventral

Belly of animal; lower surface

Meiosis

Process of creating egg or sperm

Oogenesis

Production of egg cell; oogenium-PMATC(2)- ovum+3 polar bodies

Spermatogenesis

Production of sperm cells; spermatogenium-PMATC(2)- 4 spermatozoa

Fertilization

When spermatozoa meets ovum resulting in zygote - diploid single cell; zygote undergoes series of mitotic division known as cleavage

A ___ is formed as more cells are created; when ball begins to create a hollow center

Blastula

Blastula reorganizes into a multicellular structure called a ___ by folding in on itself

Gastrula

Protostome

Animals when the blastopore will eventually become the mouth of organism; blastomeres are determinate; mesoderm begins near blastopore (between exo and endo); schitozocoelous development

Deuterostome

Animals in which blastopore will eventually become anus of organism; blastomeres are indeterminate; Mesoderm begins away from blastopore (attached to endo); enterocoelous development

Acoelomate

Do not have body cavity; solid mesodermal layer; platyhelminthes

Pseudocoelomate

Body cavity is not derived from the mesoderm, but is reminiscent of blastocoel; nemotoda and rotifera

Coelomates

Have true coelom surrounded by mesodermal tissue

Diploblastic

Arising from only 2 embryonic layers: endoderm and ectoderm

Triploblastic

Having 3 layers: endoderm, mesoderm, ectoderm

Ectoderm will become….

Skin and nervous system

Endoderm will become…

Digestive tract and respiratory

Mesoderm will become…

Muscles, skeletal, circulatory, excretory, lymphatic, reproductive

Levels of organization

Cell

Tissue

Organ

Organ system

Organism

Morula

A solid ball of cells

Polar bodies

When new cell undergoes mitosis but the daughter cells don’t grow before the next round of mitosis

5 basic common types of tissue

Epitherial, connective, fluid, muscle, nervous

Connective tissues

Arises from mesoderm; wraps around and cushions to protect organs; store nutrients (adipose), Internal support of organs (areolar), Tendons and ligaments bend to protect joints and attatch muscles to bones (dense)

Cartilege

Provides strength and flexibility while resisting wear; cushions shock where bones meet

Bones

Provides framework and strength for body; allows movement; stores calcium; contains blood forming cells

Fluid tissue

Transport food, nutrients, and waste products around body; immune response

Muscular tissues

Arises from mesoderm; 3 types: Striated, smooth, cardiac

Striated/voluntary muscles

Found in arms and legs

Smooth/involuntary muscles

Work automatically; found in intestines

Cardiac muscles

Involuntary

Muscle tissue is made so it can…

expand and contract