Lecture 2 Learning Objectives

Two Major Aspects of Biology

1. Unity
2. Diversity

How do melanized fungi generate energy?

Melanized fungi use electromagnetic (gamma rays) radiation for energy production converting it to chemical energy through electron transfer.

Definition of a cell

-The smallest unit capable of carrying out life
-a living thing is a cellular entity that acquires energy from its surroundings and is capable of reproducing, evolving and interacting with the environment

Cell vs Virus

-Viruses are not alive
-both cells and viruses have enclosed genetic information but viruses lack ribosomes
-viruses can do not harness energy and can't make copies outside of a host cell

Robert Hooke

first to observe tree bark (cork)and found that they looked like honeycomb and were uniform

Anton van Leeuwenhoek

poured blacked pepper in water (pepper infusion) and found bacteria, which he considered little animals, days later

four parts of the cell theory

1. Cells are the structural unit of life (all organisms are composed of cells)
2. Cells are the functional unit of life (smallest entities that have properties of life/ each cell is an entire organism
3. All cells are fundamentally similar in structure/or

Louis Pasteur

-supported hypothesis that cells come from pre-existing cells
-let a straight neck flask and a swan neck flask sit with previously sterilized broth for two weeks to discover that dust with microbes travelled into the straight neck flask making the broth c

Eukaryotic cells

Have a membrane bound nucleus and membrane bound organelles they are also larger

Prokaryotic cells

They are smaller with no membrane bound nucleus and no membrane bound organelles

Theory of Evolution

Mutations of organisms lead to different species

How natural selection leads to evolution

Helpful variations (heritable in DNA) accumulate among surviving members of the species (fitness advantage).

Tree of Life

the cell theory and theory of evolution by natural selection imply that all species are descended from from a single common ancestor at the root of the family of a family tree of all organisms.

Which of the following statements about evolution is TRUE?
a. Life arose from a common ancestral cell.
b. Evolution explains both the unity and diversity we see in life.
c. Natural selection drives species to change over time.
d. Variation among species i

E. All options are true

Using the phylogenic tree shown (look in lecture slides), which of the following statements is FALSE?
A. Organism A is more closely related to B than to C.
B. Organism X is the earliest comment ancestor to A and E
C. Organism C is more closely related to

C. Organism C is more closely related to A than E.