Bio final

Gregor Mendel is famous for his work with his garden pea plants. He observed several

traits and their individual patterns of inheritance. Through his F1 and F2 crosses he was able to work out two important principles, the law of ……… and the law of ……………. These principles provided us significant insight into how traits are passed from parents to offspring. He is considered the father of ………….

DOMINANCE, INDEPENDENT ASSORTMENT, GENETICS

Why do we use a punnett square? What does it specifically tell us about a cross?

To predict the phenotype and genotype potential offspring. Haploid parent cells are on the outside and diploid offspring cells are on the outside.

Dominant

Definition: Stronger trait. Example: B= brown eyes

Recessive

Definition: Weaker trait. Example: b= blue eyes

Homozygous

definition: same alleles. example: BB= shows dominant trait, bb= shows recessive trait

Heterozygous

definition: different alleles. Example: Bb= shows dominant alleles

Genotype

definition: alleles/genes. Example: BB, Bb, bb

Phenotype

definition: physical trait. Example: Blue eyes or brown eyes

Mendel concluded that certain alleles are either ………. while the others for the same gene are …….. and therefore masked phenotypically

DOMINANT, RECESSIVE

In Mendel’s F1 cross, what would you expect the potential offspring to look like(phenotypically) when a true-breeding purple flowered plant is crossed with a true-breeding white-flowered plant? (remember purple is dominant)

PP x pp = all offspring would be Pp, purple.

In Mendel’s F2 cross, based on the previous question, what was the phenotypic ratio of the offspring?

Pp x Pp = PP, Pp, pp (75% purple, 25% white)

Incomplete dominance Definition

Neither allele is dominant over the other so you see a BLEND of traits

Heterozygous is a blend

Punnett square can use the same letter or different letters depending on the problem

incomplete dominance example

Incomplete dominance key differences from Mendelian traits

Heterozygous are BLENDED

Codominance

Both alleles are dominant so they both show in the phenotype

Use two DIFFERENT capital letters in the punnett square

Codominance example

Codominance key differences from Mendelian traits

red cow crossed with white cow= spotted cow

Multiple Alleles definition

3 or more possible alleles for a trait (as a population)

Multiple alleles example

Blood type A, B, O

Multiple alleles key differences from Mendelian traits

More than two potential phenotypes

Polygenic inheritance definition

Multiple GENES contributing to one traits

Polygenic inheritance example

Polygenic inheritance Key differences from Mendelian traits

Larger range in phenotype

Sex-linked traits definition

Males are affected more than females because they have 1 X chromosome

Use XX for females and XY for males

Use the same letter for the trait such as:

X^A X^A

NOT: X^A X^B

Sex-linked example

Sex-linked key differences from Mendelian traits

Color deficiency in males

Transcription- where?

Nucleus

Transcription- main purpose

DNA —> RNA

Transcription- “Language”

DNA language (ATCG) —> RNA language (AUCG)

Transcription starts and stops at…..

Promoter and terminator

Translation- where?

Ribosome

Translation- Main purpose

RNA —> protein

Translation- “Language”

nucleic acid language (AUCG) —> amino acid language (met)

Translation starts and stops at……

Start codon, Stop codon

Point mutation definition

ONE nucleotide (letter) is affected. But there is still the same number of nucleotides in the DNA sequence. (Silent, substitution, missense, nonsense)

Point mutation example

Silent Mutation

Frameshift Mutation definition

Shift the whole reading frame of DNA.

Frameshift Mutation example

Insertion and deletion

Chromosomal Mutation definition

Mutation that affects the whole chromosome (extra chromosomes, missing chromosomes, missing PART of chromosome)

Chromosomal Mutation example

Down syndrome

Overproduction

Reproduce more than can survive

Variation

Organisms within the population vary

Selection

Some organisms survive and reproduce better than others. They are more fit.

Adaptation

Genes of the more fit organisms start to increase in the population

Stabilizing selection

The average phenotype is selected for

Directional Selection

One extreme phenotype is selected for

Disruptive selection

Both extremes are selected for

Biogeology

The study of where organisms live and where their ancestors lived in the past.

Selection pressures

Fossils

Embryology

Comparing the development of embryos in different organisms. Similarity in development shows common ancestor.

Ex. Chicken and Crocdile

Homologous Structures

Similar STRUCTURE -different function

***similar architecture (1 bone, 2 bone, little bones, digit)

EXAMPLE: Crocodile, whale fin

Vestigial structures

Previous function, but nothing now -left over

Appendix

Molecular Evidence

Molecular Evidence

Share similar DNA!

Morphological or Anatomical adaptations

Body structures

Camouflage

Mimicry

Defense mechanisms

Physiological adaptations

Cellular features

Internal changes

Poisons

Temp regulation

Allopatric speciation definition

Two populations of the same species become isolated from each other due to geographic changes

Allopatric speciation examples

River

Mountain

Ocean

Sympatric speciation

Two groups of the same species live in the same geographic location, but they evolved differently until they can no longer interbreed

Sympatric speciation example

Behavioral- different courtship rituals

Time of year they mate

Habitat

Different reproductive structures

Ecology is the study of interactions between different…….. and between organisms and the …….

Organisms

Environment

Abiotic factor=

NON LIVING

Biotic factor=

LIVING

The biosphere is all the places on earth where we find……

Life

Photosynthesizer: use the energy of the…….. to make food

Sun

Chemosynthesizers: use the energy of the……. To make food.

Chemical bonds

Herbivores: eat…….

Plants

Carnivores: eat…….

Meat

Omnivores: eat

Plant and meat

Scavengers: eat………

Dead carcasses

Ditritivores:

An animal that feeds on dead organic material

Decomposers:

Organisms that breakdown and obtain energy from dead organic matter

Organisms that occupy the same level of a food chain/Web are at the same…….. level

Trophic

Approximately…….. of energy is passed on from one trophic level to the next

10%

In the ecological pyramid below, please fill an organisms that occupy each level:

Communities of organisms(……. Factors) + the nonliving environment (…….. factors).

Biotic

Abiotic

Communities are different…………… living in the same area

Populations/species

Competition description

Organisms attempting to use ecological resources at the same time and place

Competition examples

Water, mates, nutrients, light food, space, shelter, etc.

Predation description

One organism hunt and eats another.

Predator: eats

Prey: eaten

Symbiosis description

Any intimate relationship between members of two or more different species

Mutualism

Both species benefit

Commensalism

One benefits and other is not affected

Parasitism

One benefits and another is harmed

One…….. living together in a defined area

Species

The number of organisms in an ecosystem can hold or sustain is referred to as…….

Carrying capacity

Density dependent factors

Stops a large population from getting any larger

Examples: disease, resources, predators

Density independent factors

Stop the population from growing any larger, regardless of size.

Example: humans, whether natural disaster

Positive feedback mechanism definition

Promotes the change in the system to push FURTHER away from home

Example: giving birth

Negative feedback mechanism definition

Restores the system back to homeostasis

Example: sweating