Introduction to Biology - Exam 4 Study Guide

Vector

Organism that does not cause disease but spreads infection to another host

• Malaria = mosquito

Variables changing from Climate change

• Temp

• Precip

Stronger storms, floods, drought

Hemoglobin

4 polypeptide subunits

• a subunits are identical

• b subunits are identical

each subunits binds to nonprotein = heme

Transcription

Initation

Elongation

Termination

Transcription: Initation

1) Sigma binds to RNA polymerase

2) Creases holenzyme (whole enzyme

3) Sigma binds to promoter region of DNA

4) RNA polymerase unzip double helix of DNA

5) Template strand moves trhough channel in RNA polymerase where NTPs are found

6) NTp is bound to the DNA template strand, RNA polymerization begins

Transcription: Elongation

7) RNA polymerase moves along DNA template strand, synthesizing mRNA

Transcription: Termination

8)Transtion ends when transcriotion-terminal signal is reached

9) mRNA folds on itself = hairpin

10) mRNA detach from polymerase

Splicing

Removal of introns›

• exons: coding

• introns: non-coding

1) snRPSs bind to start / end of intro and to branch sitte

2) snRNPS join together

3) Intron is cut from exon: intron froms lariat at branching point

4) Intron released + exons joined together

Capping off

1) once mRNA seperates cap is added to 5’ end

2) poly(A) tail added to 3’ end of pre-RNA

• creates mature + protect

tRNA

Interpreters for Protein Synthesis

1) tRNA attaches to mRNA molecule at anticodone + codon

2) Amino acid attaches at 3’ end›

Ribosomes - key features›

Translation: Overview

1) tRNA diffues into ribosome A side and if anticodon matches the codon of mRNA line up

Peptide bond forms between AA

3) Ribosomes moves across mRNA by one codon, and tRNAs move through the ribsomes

Translation: Initiation

1) mRNA binds to small submit of ribosome

2) Initator aminoacly tRNA bins to start codon

3) Large subunit of ribsome binds = ribosome complex

Translation: Elongation (1)

4) Incoming aminoacyl tRNA

5) Peptide-done formation

6) Translocation›

Translation: Elongation (2)

7) Incoming aminoacyl tRNA

8)Peptide-bond formation

9) Translocation

Traslation: Termination

10) Release factor binds to stop codon

11) Polypeptide + uncharged tRNAs are released

12) Ribosome subunit separate

Translation: Processing

1) Folding

2) Chem mod

• Sugar / lipid group

• Phosepate group = change shape

Gene Expression

Each cell has same gentic information

• Differnital cell expression: expression of different sets of genes in cells with the same genome

Histone

proteins that DNA is wrapped around

Nucleosome

package of DNA, histones, other proteins

• packed into 30nm fibers and attached to scaffold proteins

Chromatin

complex of DNA, proteins, histones = eukaryotic chromsomes

• framework for chromosomes

Default state: turned off

Actice state: actively being transcribed

Epigenetics

study of heritable changes in gene expression that occur without a change in the DNA sequence

Pesticdes

-Function

-Classifcation:

• Chem strucutre

• Target species

• Mode of Action

• Toxicity

-Nature

Exposure to Pesticdes

1) Acute

Irriation, death

2)Long Term

Depression, reproducice funcitons, death

DDT

• alterns methylation patterns

  • low methylation = active genes

• and can be heritary

Physiology

Study of the function of organism (how tey work)

1) Energy + resource use METABOLISM

2)Maintenance of system inegriry - HOMEOSTASIS

3) REPRODUCTION

Proximate = Mechanism + Ontology

How organisms work

• Mech: how does it work

• Ontgeny: how trait develop

Ultimate = Adaptaion + Phylogeny

How species came to form

• Adap: benefit does it add to survival

• Phy: do others have it as well? - where it come from

What all living orgnaism share

1) Energy: fuel an organism needs to maintain function

2)Cells: organziton that organisms are composed of

3)Information: genetic and enviorment = used to regulate celluar proces

4) Evolutio: organsism change over time

Cells

1) Self organizaion: metabolism

obtain energy + raw materiams from surrounding enviorment

preform various chem reaction

elimate waste product

synthesize proteins

2) Self regulation: homeostaous

detect/respond to changes

control exchange of materials

repair damages

fix abnormailites

3) Self support / movements:

move by way of strucutes that help materials move into/out of cells

4) Self-replication:

reproduce to continute existence of species + repair damage cells

LVL OF CElls organization

Tissues

Organs

Systmes

Body

Tissues:

Group of cells with similar strucures

Tissues: M

• Muscular: contract and generation of force (skeletal)

Tissues: N

• Nervouse: initation and tranmission of electral impules (brain)

Tisseus: E

• Epithelial: exchnage of materials

  • sheets: covers cover + lines (skin)

  • glands: specilizaed for secreation

    • Exocrine: outsidel (sweat)

    • Endocrine: inside (hormones)

Tissues: C

Connective: connects, supports, body arts

• Losse: attaches epithelial tissue to underlying strucutres

• Dense: tendons + ligaments that connect skeletal, muscles, bones, organs

• Support: bones + carilage that give shape

• Fluidd: cells + liquid extracellular matrix (blood)

Organ system

Group of cellular / extracellular componds that organization to perform a specific function (digestive system)

Surface-area to volume-ratio

• Volume increases faster than surface area with increased “size”

  • Small organism = increases surface area per vol

  • Larger organ = decrease surface area per vol

SA = 6 x L2 (for one cub) 6:1

Vol = L3 (for one cube) 3: 1

Metabolic Rate + Basal Metabolic Rate

• Overall rate of energy consumption by an indivdual

  • How much oxygen cosumber per gram per hour

• Resting Metabolic Rate

Inverse relation between bozy size and BMR

Thermoregulation

How to obtain heat

Endotherm: inner heat - produce own heat to warm tissue

Ectotherm: outer heat - uses the environment for heating tissue

Homotherms (same heat): keep body temp constant (mammals)

Poikilotherm (varied heat): temp fluacate depending on conductions (fish, reptiles)

Torpor

Energy-conserving physiologcal state which dereases in metabolic rate

• Hibernation: cold / low food

• Estivation: dry / hot weather