Medical Biology Chapter 4 Review

Rock Cycle may change…

physical and chemical structure of rock

Sedimentary Forces ( Forces that move sediments)

1. Running Water

2. Flowing Ice (Glaciers)

3. Wind

4. Gravity

How do sediments turn into sedimentary rock?

As more sediments build upon each other, this provides heat, and pressure which over time combines sediments into sedimentary rock.

What are sediments?

Small particles of rock, minerals, or dead organisms.

What is sedimentary rock?

Sediments that combined over time to form one larger rock.

Factors that can expose sedimentary rock?

Wind, erosion, weathering.

What is a fossil?

A remnant of an ancient organism in sediments or rock.

What conditions are needed for fossilization to occur?

1. Body of H2O with no oxygen

2. River flood plains

3. Hard-Bodied Organism ( Bones, teeth, etc)

Why are insects hard to fossilize?

They are small organisms.

What body parts are easy to fossilize? Why?

Bones and teeth because since they are less organic than flesh, skin, etc, they are able to be preserved much easier when the right conditions are met.

What are body fossils?

Remains of an organism’s bones or other part found in sedimentary rock.

What can body fossils tell us?

Shape and size, type of vore, function in food web, impression of what the organism looks like, trace origin/evolution

What are molds?

When an organism decays in a rock which leaves an impression of their exterior form within.

What are casts?

When a hollowed impression (mold) is filled with sediments that turned into rock, essentialy taking the place of organism.

What are imprints?

A 2 dimesnional outline of the organism

What are Trace Fossils?

Preservation of animal actiivty or behaviour.

What does the fossil record show?

Shows that geologic timescale.

What are sediments in layers called?

Stratas

Why are stratas important to finding the geologic timescale?

Stratats show geologic periods (or eras) seperated by many of millions of years. The oldest are at the bottom.

What are index fossils?

Fossils that are used to reliably date rock layers

What are the requirements to be used as a index fossil?

1. Organisms must live for a short time (hundreds of millions of years ago to a few million years)

2. Organisms are found widespread everywhere on Earth

3. Organisms are easily identifiable and distinguisihable from similar organisms.

4. fossils are abundant per rock layers

5. fossils are abundant in a wide/variety of sedimentary layers

What is the order of the Geologic Time Scale?(Oldest to most recent)

Precamberian → Paleozoic → Mesozoic→ Cenozoic → Present

What are fossil records used to show?

How life evolved over time as well as how the environment changed over time.

What are fossil records used to substantiate?

Tectonic Plate Movements ( The idea that tectonic plates move due to internal convection current)

What can developemental and anatomical evidence show between organisms?

These similarities help point to common ancestry and evolutionary relationships.

What is Evolution?

Biological changes that are used to evaluate and identify relationships between species of organisms

Anatomical Evidence?

The study of similar structures.

Homologous Structures

Structures that have a similar appearance or patterm, but have a different function. This points to common ancestry.

Analogous Structures

Different structures with similar function.

Vestigial Structures

Remnants of old features that lost function over time. These help provide clues to the organism’s past. It can also help find common ancestry.

Molecular Similarities

The comparison of DNA to see how closely related organisms are. More closely related organisms have more DNA that are alike.

Molecular Clocks

The use of mutation rates to measure evolutionary time. The more mutations = farther away from a common ancestor.

Mitochondrial DNA (mt DNA)

Used to trace mutations within one species. This DNA mutates 10 times faster than nuclear DNA and is passed on from mother to offspring. This DNA does not combine with other DNA.

Ribosomal RNA (rRNA)

This is used to compare organisms over large periods of time. Molecules like rRNA are used because mutations accumulate much slower.

Pseudogenes

Genes that lost function over time but still exist. These genes can also still change through mutations.

Body Plan Expression

Mutations in DNA create many different body types. the closer the arrangement of body types, the closer related the organisms are. The HOX Genes are the guide for formations of organs and placements of body parts.

Protein Sequences

This method compares how amino acids are strung up. More closely related organisms will have more.

What are the two other names for cladogram?

The Tree of Life or Phylogenetic Tree

What is the Cladogram used for?

To show evolutionary relationships between organism through different criteria.

Clade

A group of species that share a common ancestor

What is taxonomic Classification?

The classification of life and ancient organisms that have gone extinct.

Order the Taxonomic Classification from Top to Bottom

D(omain)
K(ingdom)
P(hylum)
C(lass)
O(rder)
F(amily)
G(enus)
S(pecies)

What is the modern classification called?

Tree Model of Life which has 3 domains.

Theory

Proposed explanation to a question that is supported through constant evidence and experiments.

How can populations grow exponentially?

Given a surplus of food, space, mates.

Natural Selection

The ideathat individuals with desirable traits will survive and reproduce to pass the traits onto the next generation

What are “desirable” traits?

Traits that improves an organisms fitness or change of survival and reproduction within an environment.

What did Darwin note when he was on his voyage?

All organisms seemed well-suited towards their specific environment.

How did Darwin develop his theory of Natural Selection?

He built upon the observations from past scientists and his own personal observations.

Adaptations

Process where advantageous features allow an organism to be well suited in their environment.

Tectonic Forces

Movement of tectonic plates caused by convection currents.

Geologic Uplift

The uplifting of tectonic plates.

Artificial Selection

The process where humanity becomes the selective agent for the development of certain traits or evolution within a species.

Gregor Mendel

The founding father of discovering genetics and the principle of heredity. 6 years after “ On the Origin of Species”

What did Mendel show through his work? (about heritable traits)

Traits are passed down from parent to offspring.

Traits

Certain features coded by genes found within DNA.

Alleles

Different variations off the same gene.

Meiosis

Special Cell Division where an organism produces gametes (sperm or egg cells)

Sexual Reproduction

Process where organisms procreate to have offspring.

What does sexual reproduction and meiosis do to genetic variation.

Increases genentic variation.

What does sexual reproduction do?

Produces organisms with unique combinations of traits.