unit 2 Cellular Transport - Chapter 7

What did scientists observe using the earliest microscopes.

tiny organisms

An electron microscope can magnify an object about 500,000 times. How does this magnification compare with the magnification of a compound light microscope?

500 times higher

Which statement is a fundamental principle of the cell theory?

All living things are composed of cells.

Which statement is true about bacterial cells?

They lack a nucleus and membrane-bound organelles.

Which is present only in eukaryotic cells?

nucleus

Which substance on the plasma membrane helps identify chemical signals from outside the cell?

carbohydrate chain

Which organelle converts sugars into energy?

Mitochondrion

Cilia and flagella are used to move cells through watery environments. What role do these cell parts play on stationary cells?

They move substances along the surface of the cell.

A scientist at the polar ice cap was studying an ice sample from hundred of meters below the surface. While examining the ice, the scientist found some cells from many years ago. Using an electron microscope, the scientist identified these cell structures: a cytoskeleton, mitochondrion, nucleus, cell wall, and ribosomes. What kind of organism did the scientist find?

plant

Chloroplasts are organelles that convert light energy to sugars. These organelles are found only in plants. Which organelles are found only in animals?

Lysosomes

At what point in the process of diffusion is dynamic equilibrium reached?

when there is continuous movement but no change

What is a major difference between facilitated diffusion and active transport?

Active transport moves substances against the concentration gradient.

Algal cells are placed in an isotonic solution. Additional amounts of solutes are slowly added to the solution. What happens to the cells?

They will shrink.

Which of the following is an example of passive transport?

facilitated diffusion

All cells have a

plasma membrane

Which of the following is not true of membranes?

Folded membranes do not form compartments in the cell

Who concluded that all plants are made up of living cells

Schleiden

A major difference between a compound light microscope and a transmission microscope, is that a light microscope image

can be made from living unstained materials

The scientists who first described living cells as seen through a simple microscope was

Van Leeuwenhoek

In a chloroplast the stacks of membrane sacs are called

grana

The fluid mosaic model describes a structure with

polar layers on the outside and non-polar layers on the inside

The Plasma membrane is said to be a

Mosaic model that allows other molecules to float in the membrane

Selective Permeability

The plasma membrane controls the movement of substances into and out the cell

A plasma membrane is made up of a

Lipid bilayer

Cells structure that contains digestive enzymes

Lysosomes

The sites of protein synthesis are the

Ribosomes

The small membrane bound structures in a cell

organelles

The breakdown of molecules in order to make energy in a cell

Mitochondria

In plants, the structures that creates energy

Chloroplasts

A framework for the cell within the cytoplasm

Cytoskeleton

a membrane bound for temporary storage of materials

Vacuole

The network of interconnected compartments inside the cell for detoxification and transport

Endoplasmic Reticulum

Rough ER

has ribosomes and is involved with protein synthesis

Smooth Er

Lacks ribosomes and involves the synthesis and transport of proteins

plasmodesmata

The gaps in the cell wall that allow neighboring cells to link together

Golgi apparatus

sorting and packaging

Passive Transport

Movement of particles across the membrane without energy across the concentration gradient.

ex, Diffusion, Facilitated diffusion, Osmosis

Diffusion

Movement of particles from high to low concentration

Facilitated diffusion

movement pf materials across the plasma membrane using proteins

Osmosis

Diffusion of water across a selectively permeable membrane

Isotonic Solution

same solute outside the cell as inside the cell

Hypotonic Solution

ower solute concentration than cells, causing water to flow into the cell and potentially causing it to swell or burst.

Hypertonic Solution

higher solute concentration than cells, causing water to flow out of the cell, leading to shrinkage

Active Transport

Movement of particles across the cell membrane using energy against the concentration gradient

Endo Cytosis

Process by which the cell surrounds and takes particles into the cell

Exocytosis

Secretion of material out of the plasma membrane