BIOLOGY Finals Reviewer

Evolution

Can be defined by Darwin’s phrase descent with modification

1795: Hutton

he proposed the principle of gradualism

1798: Malthus

He published his “Essay on the Principle of Population”. (Species can produce more offspring than the environment can support. Variations of the population.)

1809: Lamarck

He published his hypothesis of evolution.

1812: Cuvier

Publishes his extensive studies of vertebrate.

1830: Lyell

Published the Principles of Geology.

1831-36: Darwin

He traveled around the world on HMS Beagle

1844: Darwin

He writes his essay on descent with modification.

1858: Wallace

While studying species in the Malay Archipelago, he sends his hypothesis of natural selection.

1859

When On The Origin of Species is published by Charles Darwin

Aristotle

He proposed the Scala Naturae

Sc/ala Natur/ae

The scale by which species are ordered by how perfect they are

Paleontology

Study of fossils (Helped to lay the groundwork for Darwin’s ideas)
Largely developed by Georges Cuvier

Fossils

Remains or traces of organisms from the past, usually found in sedimentary rock, which appears in layers or strata

1. Natural Variation

2. Competition

3. Survival of the fittest

4. Organisms change over time

Four Steps of Natural Selection

Natural Variation

This naturally exists in nature (1st Step in Natural Selection)

Competition

Organisms struggle for survival: more organisms are produced than the environment can support

Survival of the fittest

Only the best adapted survives. Adaptations are important

Organisms change over time

Organisms change but they have a common descent — they have a common ancestors

Adaptations

Inherited characteristics. Increase an individual’s chance of survival and reproduction.

1. Directional

2. Stabilizing

3. Disruptive

Types of Natural Selection

Directional

A shift in the frequency of a trait in a particular direction
E.g. Horse Racing: Breeders pick horses that can run the fastest

Directional

Stabilizing

Selects for average phenotypes and against extreme pheno.

E.g. Common in stable and unchanging environments

Stabilizing

Disruptive

Selects for extreme phenotypes and against average phenotypes for being subjected to predation.

Disruptive

Artificial Selection

Humans select variations we find useful (domestic animals and crops)

Natural Selection

environment is the selective force. Only those organisms that are well adapted will survive in the wild.

Sexual selection

The species select which variations are useful (opposite of artificial selection).

Catastrophism

Speculation that each boundary between strata represents a catastrophe

James Hutton and Charles Lyell

They Perceived that changes in the Earth’s surface can result from slow continuous actions still operating today

Uniformitarianism

States that the mechanisms of change are constant overtime.

Lamarckism

Species evolve through use and disuse of body parts and the inheritance of acquired characteristics

adaption

Darwin perceived ______ to the environment and the origin of new species as closely related processes.

Natural selection

a process which individuals with favorable inherited traits are more likely to survive and reproduce

1. The Unity of Life

2. The diversity of life

3. The match between organisms and their environment

The origin of species

Descent with Modification

Summarized Darwin’s perception of the unity of life. Refers to the view that all organisms are related through descent from an ancestor that lived in the remote past (same ancestor)

Members of a population often vary in their inherited traits

Observation #1 of Natural Selection

All species can produce more offspring than the environment can support, and many of these offspring fail to survive and reproduce

Observation #2 of Natural Selection

Individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring than other individuals

inference #1 of natural selection

This unequal ability of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations

Inference #2

Homology

Similarity resulting from common ancestry

Homologous Structure

Are anatomical resemblances that represent variations on a structural theme present in a common ancestor

Vestigial Structures

Are remnants of features that served important functions in the organism’s ancestors

Evolutionary Trees

Hypotheses about the relationships among different groups

Convergent evolution

Is the evolution of similar, or analogous, features in distantly related groups.

Analogous traits

Traits that arise when groups independently adapt to similar environments in similar ways

Biogeography

The geographic distribution of species, provides evidence of evolution

Endemic species

species that are not found anywhere else in the world

1. Epithelial

2. Connective

3. Muscular

4. Nervous

Types of Tissues in Animals

Epithelial Tissue

A sheet of cells that protects the body’s sensitive systems

Connective tissue

Most abundant tissue in the anima body. Connects, binds, supports, and separates other tissues and organs.

Muscular tissue

skeletal muscle (usually attached to skeleton, voluntary), smooth muscle (covering walls of organs, involuntary), cardiac muscle (only covering the walls of the heart, involuntary)

1. Dermal

2. Vascular

3. Ground

Three parts of the tissue system for plants

Nervous Tissue

1. Transmit electrochemical signals

2. Stimulates muscle contraction

3. Affects emotions, memory, and reasoning

1. Cell Body

2. Axon

2 Main parts of the Neuron

Epidermis

The dermal tissue in nonwoody plants

Cuticle

Waxy coating that helps prevent water loss from the epidermis (plants)

Periderm

Protective tissues in woody plants

Trichomes

Outgrowths of the shoot epidermis and can help with insect defense. (hair like structures)

Vascular tissue system

Carries out transport of materials between roots and shoots

Xylem

Conveys water and dissolved minerals upward from roots into the shoots.

Phloem

Transports organic nutrients from where they are made to where they are needed

s.t.e.l.e

The vascular tissue of a stem or root is collectively called the ____

central vascular cylinder

the stele of the root in angiosperms

vascular bundles

the stele of stems and leaves

Pith

The Ground tissue internal to the vascular tissue

cortex

ground tissue external to the vascular tissue

Stem Cell

A cell that can differentiate into different kinds of cells.

1. Parenchyma

2. Collenchyma

3. Sclerenchyma

Major types of plant cells

Parenchyma Cells

retain the ability to divide and differentiate (stem cell in plants)

Collenchyma cells

Grouped in strands and help support young parts of the plant shoot

Sclerenchyma Cells

Rigid because of thick secondary walls strengthened with lignin.

1. Sclereids

2. Fibers

Two types of Sclerenchyma cells

Sclereids

Are short and irregular in shape (type of sclerenchyma cell)

Fibers

Long and slender and arranged in threads (type of sclerenchyma cell)

1. tracheids

2. vessel elements

Water-conducting cells of the xylem

Angiosperm flowers

Can attract pollinators using visual cues and volatile chemicals. Can reproduce sexually and asexually through symbiotic relationships.

Sexual Reproduction

Creation of an offspring by fusion of a sperm and egg to form a zygote (animals)

Asexual reproduction

Creation of offspring without the fusion of egg and sperm clones. Many invertebrates reproduce asexually by fission.

Sporophytes

Diploid - produce spores by meiosis and these spores grow into haploid. Dominant generation

Gametophytes

produce haploid gametes by mitosis. fertilzation of gametes produces a zygote sporophyte cell

Flowers, Double Fertilization, Fruits

Three F’s of angiosperm life

Stamen: Anther, Filament

Male reproductive system in flowers

Carpel: Stigma, Style, Ovary

Female reproductive system

Inflorescences

Clusters of flowers

Pollination

Transfer of pollen from anther to stigma

External Fertilization

Eggs shed by the female are fertilized by sperm in the external environment

internal fertilization

Sperm deposited in or near the female reproductive tract. Provides greater protective of embryos and more parental care

Amniote eggs

the embryos of some land animals develop in ____ with protective layers

Fruit

Develops from the ovary and protects the enclosed seed. Aids in seed dispersal through wind or by animals.

Species are at risk of extinction

Disadvantage of asexual reproduction

Ovaries

Female Gonads in animals

Mammary glands

Not part of the female gonads but important in mammalian reproduction