biology1406 ch 5-7, 16.3

contrast

how different one structure looks from another- enhanced by dyes

light microscope

-Uses light for illumination -Resolution 0.2 µm

electron microscope

-uses an electron beam -resolution 2 -two types of electron 1. TEM: 2D image 2. SEM: 3D image

2 categories of prokaryotes

Bacteria and Archaea

_______ proteins are embedded in biological membranes, while _______ proteins are associated with surface regions of biological membranes.

Integral; peripheral

Resolution

ability to observe two adjacent objects as distinct from one another

Bacteria

abundent, most not harmful

prokaryotic cells

do not have a nucleus or other membrane-bound organelles, they tend to be smaller and more structurally simple

A company has developed a detergent that disrupts biological membranes by mimicking the structure of their phospholipids. It is most likely that the active ingredient

has both a polar end and a non-polar end that inserts into the membrane, disturbing the interaction between existing phopholipids

Osmosis causes the movement of water from ________ to ________.

high water concentration; low water concentration

If a cell has an increased need for a particular molecule already present in a higher concentration within the cell than in the extracellular fluid, the cell might use active transport, which usually moves molecules

in a direction opposite to the one in which diffusion moves them

Phagocytosis, pinocytosis, and receptor-mediated endocytosis all involve

invagination of the plasma membrane.

Archaea

less common, often found in extreme environments

Eukaryotic cells

membrane-bound organelles, including a nucleus, tend to be larger and structurally complex

the main difference betweeen osmosis and diffusion is that

osmosis refers specifically to the movement of water, whereas diffusion refers to the movement of any molecule

bacteria cell includes

plasma membrane (barrier) cytoplasm (contained inside plasma membrane) Nucleoid (a region where genetic material found) Ribosomes(involved in protein synthesis) Outside the cell plasma membrane Cell wall (support and protection) Glycocalyx (traps water, protection) capsule (may help evade immune system) Appendages include 1. Pilli (attachement) 2.Flagella (locomotion)

all life can be places in 2 categories:

prokaryotic cells Eukaryotic cells

Magnification

ratio between the size of an image produced by a microscope and its actual size

Which of the following is most likely to be affected if a mutation occurs in clathrin?

the endocytosis of specific low-abundance molecules

there are two basic types of active transport. The difference between them is

the energy source ech uses to move substances across a membrane

A unicellular organism adapted to living in saltwater is placed in a freshwater tank. What is the likely outcome?

water moves into the cell, causing it to burst

cell theory

1. All living organisms are composed of one or more cells. 2. The cell is the basic unit of structure and organization in organisms. 3. Cells arise from pre-existing cells.

Lactose is transported via secondary active transport into bacterial cells. Which of the following would be absent from a diagram illustrating the mechanism of this transport system?

The direct use of ATP to transport lactose

Receptor-mediated endocytosis is the mechanism for transport of

cholesterol