Bio exam 1-5

Biology

the study of living things and their interactions with one another and their environments

Scientific Method

method of research with defined steps

Inductive

related observations to arrive at a general conclusion

Deductive

general principle or law to to forecast specific results

Scientific Method(steps)

1. observation

2. question

3. hypothesis

4. prediction

5. experiment

6. analyze

7. a Supported

8. b Not supported(try again)

9. Report results

Basic Science

seeks expand knowledge

Applied science

use science to solve immediate problems

Properties of life

1. Order/organization

2. Response to stimuli

3. Growth and development

4. Homeostasis/regulation

5. Energy processing

6. Adaptation/evolution

7. Reproduction

Levels of organization

1. Atom

2. Molecule

3. Macromolecule

4. Organelle

5. Cell

6. Tissue

7. Organs/organ system

8. Organism/population/communitie

9. Ecosystem

10. Biosphere

Phylogenetic tree of life

Archaea, Bacteria, Eukarya

Bacteria/Archaea

prokaryotes: single celled with no intracellular organelles

Eukarya

Multicellular organisms

Four most common elements of living organisms

Carbon, Oxygen, Hydrogen, Nitrogen

Atom

Smallest building block of life

Isotope

Form of an element with different # of neutrons

Reactants

Substances used at the beginning of reaction

Products

Substances formed at the end of reaction

Covalent bond

electrons are shared between atoms

Ionic bond

electrons are given up or gained by an atom

Polar covalent

electrons shared unequally(attracted to one nucleus more than the other)

Non-polar covalent

electrons shared equally

Hydrogen bonds

interaction between positively charged hydrogen atom and more electronegative negatively charged atom

Water important properties

1. Ions and polar molecules can dissolve

2. Can form hydrogen bonds with other polar molecules/ions

3. Cohesion —> surface tension

Surface tension

capacity of a substance to withstand being ruptured when placed under tension

Adhesion

Attraction between water molecules and other molecules

Solution with high H+

acidic

Solution with high OH-

basic

pH

concentration of H+ ions in a solution

Buffer

maintains neutral pH inside of an organism

Carbon unqieness

1. key component of macromolecules

2. can form covalent bond with 4 atoms

DNA structure

connected by hydrogen bonds

4 major macromolecules

1. Carbohydrate

2. Lipid

3. Protein

4. Nucleic acid

Monomer

individual subunits

Polymer

monomers linked together via covalent bonds

Hydrolysis

breaking down polymers into monomers using water

• one monomer receives H+ other receives OH-

Dehydration synthesis

combination of two molecules by removing a water molecule from between them(removing OH- from one and H+ from the other)

Enzyme

biological molecules that speed up reaction

3 main subtypes of carbs

1. Monosaccharides

2. Disaccharides

3. Polysaccharides

Monosaccharides

Linear or ring shaped molecules

Disaccharides

two monosaccharides linked through a dehydration reaction

Polysaccharides

many monosaccharides joined by glycosidic linkages(glucose)

• branched or unbranched

  • straight, 1 type of bond or branched out, 2 types of bonds

Lipids

non-polar hydrocarbons(hydrophobic)

Function of lipids

1. long-term energy storage

2. provide insulation

3. Building block for some hormones

4. important part of cellular membranes

Types of lipids

1. fats

2. oils

3. waxes

4. phospholipids

5. steroids

Fats and oils

two main components: glycerol and fatty acids

Saturated fats

no double bonds and solid at room temp

Unsaturated fats

contain double bonds and liquid at room temp

• monounsaturated 1 double bond

• polyunsaturated: 1< double bond

Phospholipid

two fatty acids + phosphate group attached to glycerol backbone

Phospholipid bilayer

Hydrophilic heads face aqueous solution(out)

Hydrophobic tails face in(middle of bilayer)

Steroids structure

closed ring structure with a short tail

Protein functions

1. Regulatory

2. Structural

3. Protective

4. Transport

5. Enzyme

Amino acids

monomers that make up proteins

Peptide bond formation

amino acid monomers linked by peptide bonds through dehydration synthesis

• carboxyl group of one amino acid is linked to the amino group of the incoming amino acid

Polypeptide vs proteins

Polypeptide: chain of less than 100 amino acids

Protein: multiple polypeptides

Protein structure levels

1. Primary: sequence of amino acids

2. Secondary: folding of polypeptide

3. Tertiary: 3D polypeptide structure

4. Quaternary: interaction between polypeptides

Denaturation

changes in protein structure that lead to changes in function

Nucleic acids

genetic material of living things

Two types of nucleic acids

DNA and RNA

Location of nucleic acids

1. nucleus of eukaryotic cells

2. mitochondria

3. chloroplast

RNA role

protein synthesis

RNA types

1. mRNA

2. tRNA

3. rRNA

mRNA

leaves nucleus and contains blueprint for protein synthesis

• Transcription

tRNA

bridge between nucleotides and amino acids

• translation

mRNA

assists in protein synthesis

monomer for DNA/RNA

Nucleotides

Nucleotide structure

1. nitrogenous base

2. pentose sugar

3. 1 or more phosphate group

Key features of DNA and RNA/differences between DNA and RNA

Central dogma of life

1. DNA can make copies of itself

2. DNA can be transcribed into RNA

3. RNA can be translated to protein

Magnification

enlarging the appearance of an object

Resolution

clarity and detail of an image under a microscope

Cell theory

1. Cells are the basic unit of life

2. All living organisms made of cells

3. All cells made from preexisting cells

4 common components of cells

1. Enclosing plasma or cell membrane

2. Cytoplasm

3. DNA

4. Ribosomes

Prokaryotes charecteristics

1. lack organelles

2. cell wall containing peptidoglycan

3. similar to the first cells

4. organisms in Archaea and Bacteria domains

Prokaryote structure

1. chromosomal DNA in nucleoid

2. ribosome in cytoplasm

3. cell membrane surrounded by cell wall

Factors limiting cell growth

as cells get bigger volume increases faster than surface area

Parts of a eukaryotic cell

1. plasma membrane

2. cytoplasm

3. nucleus

4. ribosomes

5. ER

   • rough and smooth

6. golgi

7. lysosomes

8. mitochondria

9. peroxisomes

10. vacuole

Plasma membrane

Cytoplasm

region between plasma membrane and nuclear envelope

Nucleus

Nucleolus

where ribosomes are assembled from RNA and proteins

Mitochondria

conversion of stored energy to ATP

Endosymbiosis

hypothesis: mitochondria/chloroplasts originated as independent prokaryotic cells because they have their own DNA and ribosomes

Peroxisomes

break down fatty acids and amino acids here and detoxify poisons

Vacuole/vesicle

storage/transport container

• vacuoles larger

Endomembrane system

organelles that work together to modify, package, and transport lipids and proteins

• nuclear envelope, lysosomes, vesicles, ER, golgi, and plasma membrane

Endoplasmic reticulum(ER)

modifies proteins and synthesizes lipids

Rough ER

• has ribosomes

• proteins modified in lumen and sent to cellular membrane or secreted from cell

• makes phospholipids for cellular membrane

Smooth ER

• few/no ribosomes on surface

• Synthesizes carbs, lipids and steroid hormones

• Detox of meds and poison

• Storage of Ca++

Golgi

proteins and lipids are sorted, packaged, and tagged here

Cytoskeleton componenets

• microfilaments

  • actin

  • movement of cell

• Intermediate filaments

  • fibrous protein

  • structure/shape

• Microtubules

  • tubulin

  • movement of vesicles/chromosomes

Centrosome

2 centrioles that lie at right angles of each other

• centrioles made of 9 microtubule triplets

Lysosome

contain digestive enzymes that break down large biomolecules and worn out organelles

Plant cell wall

made of cellulose and is outermost layer of cell

Chloroplasts

(similar to ribosomes that they have their own ribosome and DNA)

• create energy through photosynthesis

Intercellular junctions

direct channels of communication between cells

Plasmodesmata

channels that connect between cell walls to connect cytoplasm and allow material to move

Tight Junctions

Watertight seals between animal cells that prevent material from leaking

• in epithelial cells

Desmosomes

Join adjacent cells in tissues that stretch

• short proteins in plasma membrane

• only in animal cells

Gap junctions

Connect animal cells like plasmodesmata connect plant cells

• create by 6 elongated proteins that align on on each side of the cell

Facilitated passive transport

moving substances down their concentration gradient