BIOLOGY FINAL EXAM ALLIE STUDYGUIDE-MARY VERSION

Cell Division

the division of cells into two daughter cells with the same genetic material

Asexual Reproduction

reproduction that involves a single parent producing an offspring. The offspring produced are, in most cases, genetically identical to the single cell that produced them

Sexual Reproduction

offspring are produced by the fusion of two cells - one from each of two parents

Cell cycle

there are different types of cell cycles: Prokaryotic cell cycle is a regular pattern of growth, DNA replication, and cell division. The Eukaryotic cell cycle consists of 4 phases, G1, S, G2, and the M phase.

Interphase

where the cell spends 90% of its time. Contains G1, S and G2. In G1, cells increase in size and synthesize new proteins and organelles. In S, new DNA is synthesized when the chromosomes are replicated. In G2, many of the organelles and molecules required for cell division are produced.

Mitosis

Mitosis consists of the PMAT, which is prophase, metaphase, anaphase, and telophase. It allows the division of cells, the growth of cells, and the repair of cells.

Cytokinesis

the division of the cytoplasm. The process of cytokinesis is different in plant cells and animal cells.

Chromosome

genetic information that is passed from one generation of cells to another is carried by chromosomes

Prophase

first phase of mitosis, and during prophase, the genetic material inside the nucleus condenses and the duplicated chromosomes become visible outside the nucleus and a spindle starts to form.

Sister chromatid

identical copies of DNA replicated from a chromosome.

Centromere

the middle of a chromosome, where the x's come together.

Spindle apparatus

a structure that forms during cell division, primarily composed of microtubules, and is responsible for separating sister chromatids and evenly distributing them into daughter cells during mitosis and meiosis

Centriole

a circular structure that forms near the nucleus and helps form spindle apparatus

Metaphase

centromeres of the duplicated chromosomes line up across the center of the cell. Metaphase is generally the shortest phase

Anaphase

starts when sister chromatids separate. Chromosomes separate and move along spindle fibers to opposite ends of the cell.

Telophase

final step of mitosis. Chromosomes condense and begin to spread out into tangles of chromatin. The nuclear envelope re-forms, and spindle starts to break apart and the nucleolus becomes visible.

Cyclin

a family of proteins that regulate the timing of the cell cycle in eukaryotic cells

Growth Factor

external regulators that stimulate the growth and division of cells. They are important during embryonic development and wound healing.

Cancer

a disorder in which body cells lose the ability to control cell growth

Tumor

Cancer cells divide uncontrollably to form a mass of cells

Binary fission

single parent cell doubles its DNA, then divides into two cells. Usually occurs in bacteria.

Difficulties of cell size increase

The larger a cell becomes, the more demands it places on its DNA. In addition, a larger cell is less efficient in moving nutrients and waste materials across its cell membrane.

Comparison of Asexual and Sexual Reproduction

Sexual reproduction is when 2 parents create an offspring, and the offspring gets genes from both parents. Asexual reproduction is when it is a singular parent producing an offspring and the offspring is identical to the parent.

Budding

Small growth on the surface of the parent breaks off, resulting in the formation of two individuals. Occurs in yeast and some animals (like hydra).

Fragmentation

Organisms break into two or more fragments that develop into a new individual. Occurs in many plants, as well as some animals (sponges, starfish, coral).

Parthenogenesis

An embryo develops from an unfertilized cell. Occurs in invertebrates, as well as in some fish, amphibians, and reptiles.

Stages of Interphase

The stages of interphase are G1, S, and G2.

Role of Chromosomes in Cell Division

The chromosomes carry DNA which needs to be evenly distributed between daughter cells.

Parts of Mitosis

PMAT: prophase, metaphase, anaphase, and telophase.

Cytokinesis in Animal Cells

Cells are pinched in half by a belt of protein threads. After anaphase, microfilaments form around the center of the cell. Microfilaments constrict forming a cleavage furrow. The cell is completely pinched by the microfilaments and two cells form.

Cytokinesis in Plant Cells

Vesicles holding cell wall materials line up in the middle to fuse into a cell plate which separates the new cells. Following anaphase, carbohydrate rich vesicles form around the center of the cell. Vesicles fuse and the cell plate begins to form. Cell plate is completely formed, creating two separate plant cells.

Functions of Mitosis

There are three functions of mitosis: to repair injuries, to grow, and to develop.

Regulation of Cell Cycle

They are regulated by proteins called cyclins.

Cancer Cells

Some cancer cells are not cancerous, and some are. It depends on what type of tumor you have growing in your body.

Meiosis

Makes 4 genetically different daughter cells from the parents.

Genetics

The study of heredity.

Heredity

A biological process where a parent passes certain genes onto their offspring.

Genes

Are inherited from both parents through sexual reproduction and express specific traits and characteristics.

Hybrid

A heterozygous individual (represented by two letters, capital lowercase).

Pure Trait

Homozygous traits (capital capital, lowercase lowercase).

Gregor Mendel

Father of modern genetics, an Austrian monk who discovered the basic principles of heredity through experiments with pea plants.

Chromosomes

Carry genes, are visible during prophase, and are found in the nucleus.

Genotype

The genetic makeup of an individual.

Phenotype

The traits that you can see, visible traits that are being expressed.

Alleles

An alternative form of a gene that occurs on a fixed spot on a chromosome.

Dominant Alleles/Traits

Show their effect with only one copy of the allele (AA, Aa).

Recessive Alleles/Traits

Show their effect with two copies of the allele (Aa, aa).

DNA

Deoxyribosenucleic acid.

Nucleotides

Composed of a phosphate group, deoxyribose, and a base.

Frederick Griffith

Discovered the 'transforming principle' that helped lead to the discovery that DNA carries genetic information.

Oswald Avery

Discovered that DNA is the substance responsible for heredity.

Alfred Hershey & Martha Chase

Demonstrated that DNA, not protein, is the genetic material of life using radioactive labeling.

Erwin Chargaff

Discovered the percentages of adenine (A) and thymine (T), guanine (G) and cytosine (C); bases are almost equal in any sample of DNA.

Rosalind Franklin

Discovered the helical structure of DNA and contributed groundbreaking X-ray diffraction images.

James Watson & Francis Crick

Figured out that DNA is shaped like a double helix, resembling a twisted ladder.

Chargaff's Rules

Adenine always goes with thymine (Apples grow on trees); Guanine always goes with cytosine (cars go in garages).

Watson and Crick's Discovery

Discovered the double helix structure of DNA, although they stole ideas from Rosalind Franklin.

Griffith's Experiment

Griffith wondered how bacteria got people sick.

S strain

The disease causing bacteria.

R strain

The harmless bacteria.

Mouse survival experiment

His experiment was to inject a mouse with different strains of the bacteria and see which mouse survived and which one died.

Result of S strain injection

When he injected the mouse with S strain, the mouse died.

Result of R strain injection

When he injected it with R strain, the mouse lived.

Result of heat killed S strain injection

Injected it with heat killed S strain, mouse lived.

Result of mixture injection

Injected it with a mixture of heat killed S strain and live R strain, the mouse died.

Avery's Experiment

He wanted to know which molecule in heat killed bacteria was most important for transformation (T).

Avery's molecule extraction

Avery and his team extracted different molecules from the heat killed bacteria.

Enzymes used in Avery's experiment

They mixed these molecules with enzymes that destroyed proteins, lipids, carbohydrates, and some other molecules, including the nucleic acid RNA.

Transformation after enzyme treatment

The transformation still occurred even with molecules getting destroyed.

DNA breakdown in Avery's experiment

When the DNA was destroyed, the transformation did not occur.

Result of Avery's experiment

Result was DNA was the transforming factor.

Hershey-Chase experiment

The Hershey-Chase experiment, conducted in 1952, provided strong evidence that DNA is the genetic material, not protein.

Evolution

The process by which modern organisms have developed from earlier forms over long periods of time.

Charles Darwin

The father of evolution, known for developing a scientific theory of biological evolution.

Naturalist

A person who studies the natural world and its surroundings, investigating connections between organisms and their environment.

The Origin of the Species

A book written by Charles Darwin that discusses his theory of evolution based on natural selection.

Galapagos Islands

A famous stop during Darwin's journey, located off the coast of Ecuador.

Fossils

Preserved remains of an organism.

Geologist

A scientist that studies the structure and history of Earth.

Artificial selection

The process by which nature provides variations and humans select those they find useful.

Natural Selection

The process where organisms best adapted to an environment survive and reproduce more than others.

Adaptation

An inherited trait that increases an organism's chances of survival.

Fitness

The ability to survive long enough for the species to reproduce.

Darwin's Theory of Natural Selection

Occurs in four steps: Overproduction, Variation, Competition, and Selection.

Overproduction

Each species produces more offspring than can survive.

Variation

Each individual has a unique combination of inherited traits.

Competition

Individuals compete for limited resources such as food, water, space, and mates.

Selection

The individuals with the best traits/adaptations will survive and pass on their traits.

James Hutton

Known for the concept of deep time.

Deep time

The idea that Earth's history stretches back over a period so long it is difficult to comprehend.

Charles Lyell

Known for the concept of uniformitarianism.

Uniformitarianism

The idea that geological processes we see today are the same that shaped Earth millions of years ago.

Jean-Baptiste Lamarck

Proposed that organisms can change during their lifetime by selectively using or not using parts of their body.

Thomas Malthus

Noticed that humans were being born faster than people were dying, leading to overcrowding.

Overcrowding

A situation where limited food and resources lead to faster spread of diseases and potential for war and famine.

Binomial Nomenclature

The process giving an organism 2 names; the first one indicating the genus and the second the specific epithet.

Systematics

Science of naming and grouping organisms.

Taxa (Taxon)

To name organism biologists try to organize or classify living and fossil species into larger groups that have biological meaning.

Bi

Prefix that means 2-

Taxonomy

The branch of science concerned with classification, especially of organisms; systematics.