Study Guides (400,000)
CA (160,000)
UTSC (10,000)

BIOB10H3 Study Guide - Midterm Guide: Matthias Jakob Schleiden, Hans Driesch, Rudolf Virchow

Biological Sciences
Course Code
Tanya Da Sylva
Study Guide

This preview shows pages 1-3. to view the full 38 pages of the document.
Cells: Rayana Alawie
1.1 The Discovery of Cells:
Robert Hooke: Discovered cells by looking through a microscope at cork cells
Leeuwenhoek: the first to examine a drop of pond water under the microscope and
observe the teeming microscopic animalcules = bacteria.
Matthias Schleiden: (1839) a German lawyer turned botanist concluded that plants
were made of cells and that the plant embryo arose from a single cell.
Schwann concluded that the cells of plants and animals are similar structures and
proposed these two tenets of the cell theory:
All organisms are composed of one or more cells.
The cell is the structural unit of life.
Rudolf Virchow, a German pathologist, had made a convincing case for the third
tenet of the cell theory:
Cells can arise only by division from a preexisting cell.
1.2 Basic Properties of cells:
Cells are the smallest units of life. Death is most basic property of life.
Cells obtained from a tumor called HeLa cells (by George and Martha Gey): became
the first human cells to be kept in culture for a long time. (grown in vitro = outside
the body ina cultural medium)
Cells are Highly complex and Organized:
oMore complex= less tolerance of errors.
oComplex structure matches the function of the cells
oEx epithelial cells lining the intestine have microvilli on the apical
ends of the cells that facilitate the absorption of nutrients. Apical ends
have protein actin to help project the microvilli outward. Basal end = a
lot of mitochondria
Cells Possess a Genetic Program and the means to use it:
oInformation is packaged into a set of chromosomes that occupies the
space ofa cell nucleus
oGene store and contain info. For constructing cellular structures.
oMutations lead to biological evolutions
Cells are capable of producing more of themselves:
oMost cells reproduce via mitosis into daughter cells.

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Cells: Rayana Alawie
oSome cells (oocytes) undergo division were only half genetic material is
Cells Acquire and utilize energy:
oLight energy is converted by photosynthesis into chemical energy that
is stored in energy-rich carbohydrates, such as sucrose or starch.
oCells expend an enormous amount of energy simply breaking down and
rebuilding the macromolecules and organelles of which they are made.
(turnover in order to maintain integrity of cell components.)
Cells Carry out a variety of chemical reactions:
oVia enzymes.
oSum of chemical reactions in a cell = Metabolism.
Cells engage in mechanical Activities:
oMaterials are transported, assembled and disassembled and in many
cases the cells actually move. Motor Proteins.
Cells are able to respond to stimuli:
oReceptors help cells interact with other cells and the environment.
Cells are capable of self regulation:
oMost evident when cells break down.
oEXP: Hans Driesch, a German embryologist, found that he could
completely separate the first two or four cells of a sea urchin embryo
and each of the isolated cells would proceed to develop into a normal
Cells Evolve:
oThought that cells evolved from a pre-cellular life form which evolved
from nonliving organic materials.
1.3 Two Fundamentally Different Classes of Cells:
1)Prokaryotic: (pro-before; karyon-nucleus)
-Ex: Bacteria, Cyanobacteria
-Structurally simpler.
2)Eukaryotic: (Eu- true)
-Ex: Protists, Fungi, Animals, Plants
-Structurally more complex

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Cells: Rayana Alawie
Similarities between Eukaryotes & Prokaryotes:
oBoth types of cells share common structural features -cell membrane,
cell walls (same function, different chemical composition): Ribosomes:
Non membrane bound that help make protiens.
oBoth types of cells share an identical genetic language
oBoth types of cells share a common set of metabolic pathways
(photosynthesis and protein synthesis, glycolysis, TCA cycle)
oATP located in the plasma membrane of prokaryotes and the
mitochondrial membrane of eukaryotes)
oProteasomes (protein digesting structures) of similar construction
(between archaebacteria and eukaryotes)
Characteristics That Distinguish Eukaryotes From Prokaryotes
oEukaryotic cells are internally much more complex (structurally and
-Ex: ER= cells protein and lipids are manufactured. , Golgi= materials
are sorted modified and transported., Lysosomes, Endosomes,
Peroxisomes, glyoxisomes, mitochondria, chloroplast, flagella, cilia
- Prokaryotes have nucleoid (poorly demarcated cell region)
oEukaryotes have complex cytoskeletal system
-Contains microfilaments, microtubules and motor proteins, Endo and
oMost eukaryotes have significantly more DNA :
-Prokaryotes have a single circular chromosome.
-Eukaryotes DNA is tightly compressed into chromatin.
oNo mitosis or meiosis in prokaryotes: In eukaryotes:
-Presence of 2 copies of genes per cell (diploid)
-Uses micro tubules
-Prokaryotes can reproduce non sexually except conjugation
(forms bridge pilus and exchange genes)
Types of Prokaryotic Cells:
a.Extremophiles: live in inhospitable environemnts
b.Methanogens: Convert CO2 and H2 into methane
c.Halophiles: Love salty environments
d.Acidophiles: Love acidic environments
e.Thermophiles: Love high temp. environments
f. Hyperthermalophiles: live in hydrothermal vents of the ocean floor
2)Bacteria (Eubacteria):
a.Mycoplasma: smallest known cells
You're Reading a Preview

Unlock to view full version