Domain 1-Cells and Heredity Teacher Notes

Domain 1-Cells and Heredity Teacher Notes

I. The cell (basic unit of living things)

A. There are 2 basic types of cells:

1. Eukaryotic cells – these cells have a true

nucleus and organelles. All plants, animals, fungi,

and protists are eukaryotes.

2. Prokaryotic cells – these cells do not have a

true nucleus or organelles. Examples of

prokaryotes are bacteria.

B. Parts of the cell-need to know terms

1. Cell membrane-allows for materials to enter and

leave the cell (gatekeeper; communicator)

Click here to view cell membrane video (with audio)

2. Nucleus- controls cell functions (the brain);

houses the DNA

3. Mitochondria- gives cell energy (powerhouse);

site of cellular respiration

4. Ribosome- site of protein synthesis; where

proteins are made

5. Vacuole- membrane bound sac that stores

nutrients or water. Vacuoles are large in plant cells

and play a role in turgor pressure.

6. Lysosome- stores digestive enzymes and/or

wastes

7. Endoplasmic reticulum- two types: rough and smooth.

Smooth ER is important in the synthesis of lipids and

membrane proteins. Rough ER is important in the

synthesis of other proteins.

8. Golgi apparatus- The Golgi apparatus modifies, sorts,

and packages macromolecules for cell secretion

(exocytosis) or for use within the cell. It primarily

modifies proteins delivered from the rough ER, but is

also involved in the transport of lipids around the cell,

and the creation of lysosomes.

9. Cell wall (PLANT ONLY)- rigid outer wall of cell;

non-living; made of cellulose

10. Chloroplasts (PLANT ONLY)- where

photosynthesis takes place

Click here to review cell parts

B. The Cell Theory

1. All organisms are composed of one or more cells.
2. The cell is the basic unit of structure and function in organisms.
3. All cells are produced from other cells.

C. Cell Communication and Material Movement

1. Homeostasis- self-adjusting mechanism that helps

to maintain your internal environment;

maintenance of a steady internal environment

in face of a changing external environment

(example: temperature-body sweats, fever flush)

Click here for a video example of homeostasis (audio)

2. Diffusion- movement of materials from a higher

concentration to a lower concentration

3. Osmosis- diffusion of water across a semi-permeable

membrane

Click here to view osmosis video (no audio)

For an interactive example of the three types of environments, click here.

For another interactive demo, Click here and drag to “There are three possible relationships that cells can encounter when placed into a water solution.”

Plasmolysis- loss of water by osmosis in a water plant

Click here for an example of plasmolysis of Elodea

4. Transport

a. Passive transport is the movement of

materials that does not require energy.

Diffusion, osmosis and facilitated diffusion

are examples of passive transport.

b. Active transport requires the use of energy

usually from ATP, a compound in which

energy is stored in living systems.

(An analogy between ATP and rechargeable batteries is appropriate. The batteries are used, giving up their potential energy until it has all been converted into kinetic energy and heat/unusable energy. Recharged batteries (into which energy has been put) can be used only after the input of additional energy. Thus, ATP is the higher energy form (the recharged battery) while ADP is the lower energy form (the used battery). When a phosphate is cut loose, ATP becomes ADP (Adenosine diphosphate), and the stored energy is released for some biological process to utilize. The input of additional energy (plus a phosphate group) "recharges" ADP into ATP.

Click here for active transport video (with audio)

C. Cell Chemistry

1. most important compounds

2. Photosynthesis

a. Starts with carbon dioxide, CO2 and water, plus

sunlight

b. ends with glucose (sugar), C6H12O6 and oxygen,O2

c. stores energy from sunlight in the sugar glucose

d. occurs in the chloroplasts

3. Respiration

a. starts with glucose (sugar), C6H12O6

b. ends with carbon dioxide, CO2, water, and

ATP (energy molecule)

c. takes energy from glucose and uses it to run

the cell’s processes

d. occurs in the mitochondria

Click here for respiration video clip (with audio)

4. Comparison of photosynthesis and respiration.

sunlight

photosynthesis 6 CO2 + 6H2O  C6H12O6 + 6O2

chlorophyll

respiration C6H12O6 + 6 O2  6 CO2 + 6 H2O + energy

III. Cell Reproduction

1. Mitosis- reproduction of regular (body, somatic)

cells.

a. interphase (cell growth period-DNA is replicated)

b. prophase (DNA coils, spindle fibers appear)

c. metaphase (Chromosomes line up at the middle

of the cell)

d. anaphase (chromatids separate and are

pulled to opposite sides of the cell)

e. telophase (spindle fibers disappear, cell

cytoplasm divides in two-cytokinesis)

f. daughter cells have the same number of

chromosomes as parent cell

Plant Mitosis

PMAT

Interphase Prophase Metaphase Anaphase Telophase

View Mitosis Video Clip

2. Meiosis-reproduction of sex cells (gametes)

a. cell goes through same phases as mitosis but twice

b. in a second division, chromosome number is

halved (n)

c. daughter cells have half the number of chromosomes

as parent cell

Or egg

Meiosis Video Clip

C. Chromosomes

1.. DNA-deoxyribonucleic acid

a.. located in the nucleus

b. made of nucleotides which are composed of

phosphate groups, deoxyribose sugars, and bases

c.. bases-adenine, guanine, cytosine, and

thymine

d. adenine pairs with thymine (A-T) and guanine

pairs with cytosine (G-C)

e. shape of DNA is a double helix (twisted ladder);

double stranded

Click here to view DNA structure video (with audio)

2. RNA

a. made in the nucleus and then moves to the

ribosome

b. made of nucleotide- phosphate groups, and

ribose sugars, and bases

c. bases-same as DNA except thymine is

replaced by uracil

d. adenine pairs with uracil (A-U) and guanine

pairs with cytosine (G-C)

e. single-stranded

f. three types-messenger RNA, mRNA; transfer

RNA, tRNA; ribosomal RNA, rRNA

3. Protein synthesis

a. replication- copying of DNA; occurs during

interphase

Click here for DNA replication video clip (audio)

b. transcription-occurs in the nucleus, messenger

RNA copies the DNA code, then mRNA leaves

the nucleus

Click here for transcription video clip (audio)

c. translation-occurs on the ribosomes, transfer

RNA brings the nucleotides to the ribosome so

that the correct protein can be synthesized

Click here for translation video clip

d. mutation-sudden change in the code

Click here to view protein synthesis

IV. Genetics and Heredity

A. Heredity-study of the passing of traits from parent

to offspring.

1. allele-gene forms ex T-tall or t-short

2. traits

a. dominant-trait that is seen or that overrides

the rest (T)

b. recessive (t)

3. phenotype-the way an organism looks; the

expression of a trait

ex. Tall, short

4. genotype-the actual gene make-up ex TT, Tt, tt

5. homozygous-trait with the same alleles (TT, tt)

6. heterozygous-trait with different alleles (Tt)

7. offspring-children

B. Monohybrid Cross-a parental cross of one trait.

Use a Punnett Square to determine the offspring of

the cross.

View a Punnett square video clip

What are the possible genotype and phenotype of the

offspring of a cross between two heterozygous

parents? Tt X Tt

T t

Genotype ¼ TT, ½ Tt, ¼ tt or 1:2:1

Phenotype ¾ tall, ¼ short 3:1

C. Incomplete or Blended Dominance-neither gene is

dominant

RR=red flower RW=pink flowerWW=white flower

What are the possible genotype and phenotype of

the offspring of a cross between two heterozygous

parents? RW X RW

R W

Genotype ¼ RR, ½ RW, ¼ WW

Phenotype ¼ red, ½ pink, ¼ white

This website has more problems. Do some!!

http://www.ksu.edu/biology/pob/genetics/mod5_class3_problems.htm

V. Classification

A. Classification categories from largest to smallest are

Kingdom, phylum, class, order, family, genus, species

B. Eukaryotes

1. Protista Kingdom

a. Protista are simple, predominately

unicellular eukaryotic organisms.

b. Examples includes slime molds,

euglenoids, algae, and protozoans.

2. Fungi Kingdom

a. Fungi are unicellular or multicellular

organisms with eukaryotic cell types.

The cells have cell walls but are not

organized into tissues. They do not carry

out photosynthesis and obtain nutrients

through absorption.

b. Examples include sac fungi, club fungi,

yeasts, and molds.

3. Plantae Kingdom
a. Plants are multicellular organisms

composed of eukaryotic cells. The cells

are organized into tissues and have cell

walls. They obtain nutrients by

photosynthesis and absorption.

b. Examples include mosses, ferns,

conifers (gymnosperms), and flowering

plants (angiosperms).

4. Animal Kingdom

a. Animals are multicellular organisms

composed of eukaryotic cells. The cells

are organized into tissues and lack cell

walls. They do not carry out

photosynthesis and obtain nutrients

primarily by ingestion.

b. Examples include invertebrates

(sponges, worms, and arthropods) and

vertebrates (fish, amphibians, reptiles,

birds, and mammals).

B. Prokaryotes

1. Archaea (archaebacteria)-ancient bacteria

a. Archaea often live in extreme environments.

b. They include organisms which live in harsh

anaerobic environments such as hot springs,

deep ocean volcanic vents, sewage treatment

plants, and swamp sediments.

2. Bacteria (eubacteria)-“true” bacteria

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