Exercise 4: Cell Structure and Function

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Exercise 4 Cell Structure and Function
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Two Main Types of Cells

• There are two main types of cells.
• 1. Prokaryotic cells (eubacteria and
  archaebacteria)
• Do Not contain a true nucleus, only a nucleoid
  region of DNA
• Do Not contain membrane bound Organelles
• 2. Eukaryotic cells (plants, animals, and fungi)
• Contain a true membrane bound nucleus
• Contain other membrane bound Organelles in
  addition to the Nucleus

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Two Main Types of Cells
Typical Prokaryotic Cell
Typical Eukaryotic Cell
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Typical Animal Cell
Nucleus
Peroxisome
Cytoskeletal Components
Lysosome
Rough Endoplasmic Reticulum
Centrioles
Smooth ER
Plasma Membrane
Golgi Body
Mitochondrion
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Typical Plant Cell
Central Vacuole
Golgi body
Components of cytoskeleton
Rough ER
Mitochondrion
Nucleus
Chloroplast
Plasma Membrane
Cell Wall
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Exercise 9 Mendelian Genetics
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Overview of what Mendel Observed

• The traits displayed by offspring are dependent
  upon inheritable information from the parent.
• What we now know is that this inheritable
  information is Genes contained in DNA.

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Genetic Terms

• Gene a specific region of DNA that direct the
  synthesis of a specific product that controls one
  or more specific traits.
• Diploid organisms have pairs of genes on pairs of
  homologous chromosomes.
• Alleles different molecular versions of the
  same gene.
• Dominant alleles have strong effects that
  overwhelm
• Recessive alleles the overwhelmed allele
• True-breeding lineage when the offspring
  inherit a pair of identical alleles for a trait
  generation after generation.
• Hybrids offspring which possess non-identical
  alleles for a trait.
• Homozygous when both alleles of a pair are
  identical.
• Heterozygous when both alleles of a pair are
  not identical.

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Genetic Terms

• Dominant alleles are usually depicted using
  CAPITAL LETTERS and recessive alleles are usually
  depicted using lowercase letters.
• Homozygous Dominant AA
• Homozygous Recessive aa
• Heterozygous Aa
• Genotype refers to the alleles an individual
  carries (the genetic make up).
• Phenotype refers to the observable traits of an
  individual. (outward appearance)
• P parental generation
• F1 first-generation offspring
• F2 second-generation offspring

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Monohybrid Cross

• P True breeding Red eyed Male (RR) and true
  breeding Sepia (brown) eyed female (rr)
  RR x rr
• F1 All F1 offspring are red eyed heterozygotes
  (hybrids) Rr. Red is dominant to Sepia.
• We are going to intercross the F1 offspring. Rr
  x Rr

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Monohybrid Cross
RR X rr
Rr
Rr X
R
r
R
R
RR
Rr
R
Rr
r
Rr
rr
rR
r
rR
r
rR
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Drosophila (Fruit Flies)

• The male is generally smaller.
• The male has a more rounded abdomen than the
  female. The female has a pointed abdomen.
• The male has sex combs on the forelegs.
• Dorsally, the male is seen to have a black-tipped
  abdomen, whereas the female appears to have only
  dark lines at the tip.
• Ventrally, the abdomen of the male has a dark
  region at the tip due to the presence of
  claspers this dark region is lacking in the
  female.

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Procedures

• Make fly incubation chamber.
• Anesthetize the flies.
• Count out and separate 10 male and 10 female
  flies.
• Combine the flies and place on the side of the
  incubation tubes and turn the tubes in.