Biology - Cellular Structure, Genetics

What are the components of cell theory?

1. Cell is the basic unit of life

2. All living things come from pre-existing cells

3. All livings things are made up of cells

What are the levels of organization?

1. Atom; Carbon and Oxygen

2. Molecule; H2O (micro)

3. Macromolecules; protein, carbs, lipids

4. Organelle

5. Cells

6. Tissue

7. Organ

8. Organ System

9. Organism

What are the 3 domains of life?

• Bacteria

• Archaea

• Eukarya

What are the characteristics of prokaryotes?

Domain: Bacteria and Archaea

• No nucleus

• No membrane bound organelles

• Smaller

What are the characteristics of eukaryotes?

Domain: Eukarya (Fungi, Protists, Animals, Plants)

• Nucleus

• Membrane bound organelles

• Larger

What are the 4 cellular structures that all living organisms must have?

1. DNA (nucleoid region)

2. Cytoplasm

3. Plasma Membrane

4. Ribosome

What is the function of the cell membrane?

• Uses selective permeability to maintain homeostasis of the cell

What is the function of the cytoskeleton?

• Uses network of fibers to provide structural support

What is the function of the ribosome?

• Synthesizes proteins

What is the function of the nucleus?

• Membrane bound organelles containing DNA as chromatin (condenses to chromosomes)

What is the function of the nucleolus?

• Area inside nucleus, RNA, and protein that makes ribosomes

What is the function of smooth vs. rough ER?

• Smooth: detoxification and synthesizes lipids

• Rough: site of protein synthesis

What is the function of the golgi apparatus?

• Uses enzymes to modify proteins and lipids

What is the function of the lyzosome?

• Contains digestive enzymes that break down excess or invaders

What is the function of vacuoles?

• Engulfs waste products

What is the function of vacuoles in plants?

• Maintains water balance

What is the function of chloroplasts in plants?

• Plastid, site of photosynthesis

absorb green

What is the function of mitosis versus meiosis ?

• Mitosis: produces somatic (bodily) cells

• Meiosis: produces sex cells (gametes)

What is the primary purpose of meiosis?

• To lower/reduce the amount of DNA in cells

to allow for combination of 2 sex cells

What is the result of a mitosis?

• 2 identical daughter cells

2n to 2n (diploid

What is the result of meiosis?

• 4 different daughter cells

2n (diploid) to 1n (haploid)

What are the phases of mitosis and meiosis?

• Mitosis; PMAT

• Meiosis; PMAT two times

What are the cycles of the cell cycle in order?

1. G1

2. S Phase: synthesis (DNA Replication)

3. G2

4. M Phase

What occurs in prophase of mitosis?

• Chromosomes condense and become visible

What occurs in the metaphase of mitosis?

• Chromosomes line up in the middle of the cell

What occurs in the anaphase of mitosis?

• Spindle fibers pull chromosomes apart to become chromatids

What occurs in telophase and cytokinesis?

• Chromosomes reach opposite sides and cleave furrow appears

split into 2 identical daughter cells

What occurs in prophase I of meiosis?

• Chromosomes condense and pairing of homologous pairing of chromosomes

What occurs in metaphase I of meiosis?

• Homologous pairings of chromosomes line up in the middle

CROSSING OVER/RECOMBINATION same thing

What occurs in anaphase I of meiosis?

• Spindle fibers pull homologous pairings away from each other

What occurs in telophase I and cytokinesis of meiosis?

• Chromosomes reach opposite sides and cleavage furrow form; cytoplasm splits

Haploid (1n)

What occurs in prophase II of meiosis?

• Daughter contains half of chromosomes

Haploid

What occurs in metaphase II of meiosis?

• Chromosomes align in the middle

What occurs in anaphase II of meiosis?

• Spindle fibers pull chromosomes apart forming chromatids

What occurs in telophase II and cytokinesis of meiosis?

• Chromosomes move to opposite sides and cleavage furrow forms in both

splits into two separate cells

What occurs in nondisjunction?

• Malfunction during meiosis; sex cells with wrong number of chromosomes

e.g Down Syndrome 3 copies of chromosome #21

What are chromosomes?

• Tightly coiled DNA around histone protein

copied DNA

What is a gene?

• Length of DNA containing instructions for proteins that express traits

What is a regulatory gene?

• Non coding segment on DNA producing proteins/RNA that control gene expression

What is the role of DNA?

• Deoxyribonucleic acid: contains instructions to code for protein, double helix

What are the components of DNA?

• Phosphate, deoxyribose sugar, nitrogenous base

What is the function of nitrogenous bases? For DNA?

• Code for traits

DNA; Adenine, Thymine, Cytosine, Guanine

What are the bonds that hold the nitrogenous bases together?

• Hydrogen bonds

What is the role of RNA?

• Carries instruction from DNA for protein synthesis

What are the three types of RNA? Their function?

1. Messenger RNA: carries genetic info. outside of nucleus

2. Ribosomal RNA: makes up ribosome

3. Transfer RNA: decodes mRNA into a protein (AA)

What stages make up prrotein synthesis?

1. Transcription

2. Translation

What is the process of transcription?

Process of making RNA strand based on DNA sequence

1. RNA polymerase unwinds DNA template strand (3’ to 5')

2. RNA polymerase forms mRNA stand (5’ to 3')

3. mRNA strand exits through nuclear pores

What is a codon? An anticodon?

• Codon: 3 base pair sequence of mRNA

• Anticodon: 3 base pair sequence of tRNA

What is the process of translation?

Process of translating mRNA sequence to AA to form polypeptides

1. mRNA strand moves through ribosome, with correspond

2. tRNA matches anticodon with codon

3. AA detaches from tRNA forming polypeptides

What is an allele? Two types?

• Allele: different versions (copy) of a gene

1. Dominant: always expressed

2. Recessive

What is a genotype versus a phenotype?

• Genotype: genetic makeup of individual, e.g. Ff, FF, ff

• Phenotype: physical appearance of trait based on genetics

ratio not always the same

What is a monohybrid punnett sqaure?

• Mix between individual genotypes: Ff x Ff

2 × 2

What is a dihybrid punnett square?

• Two traits controlled by two genes: FFdd x ffdd

4 × 4

What is incomplete dominance?

Nonmendelian genetics

• Blending between alleles (red + white flower = pink flower)

What is codominance?

Nonmendelian genetics

• Both alleles expressed (black + white = black and white spots)

What is multiple alleles?

Nonmendelian genetics

• Blood groups; A, B, O

What is dehydration synthesis versus hydrolysis?

• Dehydration synthesis: forming bonds by removing water (requires energy)

• Hydrolysis: breaking down bonds by adding water (releases energy)

What are carbohydrates made up of? Shape?

• C, H, O atoms with hexagonal shape

What are the functions of carbohydrates?

• Provide structural support, generate ATP, short term storage

What are the monomers and polymers of carbs?

• Monomers: glucose, maltose

• Polymers: starch, glycogen, cellulose, chitin

What are the monomers of lipids? 3 Types?

• No true monomer; hydrophobic

1. Fats

2. Triglycerides

3. Steroids

What are the function of fats? Structure?

AKA triglycerides

• Energy storage, insulation e.g. oils, butter, meat

Glycerol + 3 Fatty Acid tails

What are the functions of phospholipids? Structure?

• Form cell membrane

Glycerol + Phosphate head + 2 fatty acid tails

What are the functions of steroids?

• 4 ring, cholesterol sex hormones, chemical messengers

What are proteins? Hydrophobic or hydrophilic?

• Chains of amino acids; both hydrophobic and hydrophilic

What are the functions of proteins?

• Structural (cell membrane), cell receptors, enzymes, antibodies, hormones, gene

What are nucleic acids? Monomers?

• DNA and RNA, containing all genetic information

monomer: nucleotide

What is DNA versus RNA?

• DNA: double stranded, storing genetic information

• RNA: single stranded, carries genetic information for proteins

What are the 3 types of RNA? Function?

1. Messenger RNA: genetic code exiting nucleus

2. Ribosomal RNA: catalyze protein synthesis

3. Transfer RNA: carries AA

What organisms make up microbes?

• Bacteria, Archaea, Fungi, Protozoa, Animals (Helminthes)

What is pathogenic versus virulence?

• Pathogenic: the ability of a bacteria or virus to cause disease

• Virulence: the severity or harmfulness of a pathogen

What are the characteristics of viruses? Structure?

• DNA or RNA surrounded by capsid (protein)

acellular, obligate intracellular parasite

What are examples of viruses?

• Influenza, measles, HIV

What are the characteristics of bacteria? Ex?

• Unicellular, lack nucleus, varying pathogenicity, staph, strep

e.g. mycoplasma: lacks cell wal, chlamydia, strep throat, pneumonia

What is the difference between gram positive and gram negative bacteria?

• Gram +; purple, thick PG cell wall

• Gram -; pink, thin PG cell wall

What are the characteristics of fungi?

Eukaryotes

• Chitin cell wall, asexual or sexual, unicellular (yeast) or multicellular (mold)

What are the feeding requirements of many fungi? What they particularly harmful to?

• Parasites or decomposers

harmful to immunocompromised people

What are protozoa?

• Unicellular eukaryotes, not closely related

What are the examples of protozoa?

• Giardiasis, dysentery, malaria, African Sleeping sickness

What are helminthes?

• Multicellular eukaryotes, parasitic worms

What are the types of helminthes?

1. Round-hookworms

2. Flat-tapeworms

3. Flute- liver flukes

What are ectoparasites?

• MItes, bedbugs, lyme disease

What are the 3 ways that infectious disease are transmitted?

1. Direct: skin to skin contact, droplet, fluids

2. Indirect: airborne spread, in air

3. Biological and Mechanical vectors

What are the function of Transmission versus Scanning Electron Microscope?

• TEM: internal structures

• SEM: detailed visualization of 3D organisms, surface

What occurs in an autosomal recessive disorder?

• Two heterozygote carriers for a disease pass on trait

What occurs in an X linked disorder? What is the common mode of transmission?

• Gene carried on X chromosome

Unaffected carrier mother to son

What is the ABO blood system notation?

• i^0 i^B: B

• i^0 i^A: A

• i^A i^B

What are the 3 types of endocytosis?

1. Pinocytosis: ingestion of fluids, nonspecific

2. Phagocytosis: engulfing of particles of cells, pathogens

3. Receptor mediated endocytosis: targets LDLs, forming vesicle

What are the phases of bacterial growth?

1. Lag

2. Log

3. Stationary

4. Death

What is the path of infection?

1. Infectious agent

2. Reservoir

3. Portal of exit

4. Method of transmission

5. Route of entrance

6. Susceptible

What are the proteins of cytoskeleton?

1. Microfilament

2. Intermediate fibers

3. MIcrotubules

What are the 3 shapes of epithelial cells?

1. Squamous

2. Cuboidal

3. Columnar

What are the 3 arrangement of epithelial cells?

1. Simple

2. Pseudostratified

3. Stratified

What are examples of where stratified epithelia are found?

• Mouth, esophagus, exterior skin

What are examples of where simple columnar epithelia are found?

• Digest tract, goblet cells

What are examples of where simple squamous epithelia are found?

• Where filtration or diffusion