TAKS Review

Cell Structure, Function

And Energy

Controls what enters and leaves

makes proteins

packages proteins

provides energy : site of cellular respiration, conversion of food energy into usable energy (ATP)

Transport system

Breaks down old cell parts

Cell Part Function Cell membrane Controls what enters and leaves the cell

Nuclear membrane Controls what enters and leaves the nucleus

Nucleus Control center of the cell

Chromosomes Genetic information in the nucleus

Endoplasmic Reticulum Transport system in cell

Ribosome Organelle makes proteins

Golgi Body Organelle packages proteins

Vacuole Stores water and/or waste

Lysosome Breaks down old cell parts

Mitochondria Organelle for cellular respiration – provides energy

Practice Question

Which of these is a characteristic of body cells that require large amounts of energy?

A They have a large number of mitochondria.B They have a supplementary Y

chromosome.C They have a two-layer membrane.D They have a storage area for albumin

proteins.

A

Cellular Energy

Photosynthesis Cellular RespirationConverts sunlight energy into high energy sugars

Converts high energy sugars into usable energy

(in the form of ATP)

Takes place in the chloroplast

Takes place in the cytoplasm and mitochondria

Occurs mainly in plants and some bacteria

Occurs in all organisms

6O2 + C6H12O6 6CO2 + 6H2O + EnergyEnergy

oxygen + glucose carbon dioxide + water + ATPATP

6CO2 + 6H2O + EnergyEnergy 6O2 + C6H12O6

carbon dioxide + water + sunlightsunlight oxygen + glucose

Photosynthesis

Cellular Respiration

Glycolysis

A little energy released

Oxygen No oxygen

Cellular Respiration

LOTS of energy

released

Fermentation

High Energy Sugars

Aerobic AnAerobic

Energy conversion within an animal cell would be severely limited by removal of the cell’s —

A mitochondria

B chloroplasts

C plastids

D lysosomes

Practice Question

A

Which molecule provides most of the energy used to drive chemical reactions in cells?

F DNA

G RNA

H ATP

J ADP

Practice Question

H

Transport across the membrane

Purpose: to move nutrients and wastes in and out of the cell and maintain… Homeostasis

The lipid bilayer is selectively permeable; only small, nonpolar molecules can pass. Other molecules need carrier

or channel proteins.

Cell Membrane Structure

•Concentration is a measurement of the amount of solute (in grams) compared to the volume of the solution (in liters)

•Grams per liter or g/L

•Concentrations change as particles and/or water move into or out of the cell

Movement can be passive or active.

PASSIVE ACTIVE

NO energy required Needs energy

Simple diffusion

Facilitated

diffusion

Osmosis

Endocytosis Pinocytosis

Phagocytosis

Exocytosis

Diffusion vs. Osmosis

• Diffusion is the movement of PARTICLES from areas of high concentration to areas of low concentration

• Osmosis is the movement of WATER from areas of low solute concentration to areas of high solute concentration; water moves because the particles can’t

Salt is a solute. When it is concentrated inside or outside the cell, it will draw the water in its direction. This is why you get thirsty after eating something salty.

Simple Rule to remember:

SALT SUCKS

What is Active Transport?

Energy is used to move selected molecules into a cell, even if they are at a low concentration.

   

Saltwater fish remove extra salt from their body by active transport through the gills. What is the result of this activity?

A The salt becomes more chemically active.B Water balance is maintained in the blood.C The rate of energy production is

decreased.D The cell membrane becomes less

permeable to water.

Practice Question

B

When a sea urchin egg is removed from the ocean and placed in freshwater, the egg swells and bursts. Which of these causes water to enter the egg?

A CoagulationB Sodium pumpC Active transportD Osmosis

Practice Question

D

Practice Question

On a hot summer day, a road-crew worker perspires and then feels thirsty as her body temperature increases. This response is an example of-A. releasing enzymes

B. decreasing respiration

C. assimilating proteins

D. maintaining homeostasis

D

Practice Question

Which of these is a function of the cell membrane in all cells?

A Producing cellular nutrientsB Preserving cellular wastesC Neutralizing chemicalsD Maintaining homeostasis

D