Chapter 4 The Cell in Action Flashcards
the movement of particles from regions of higher density to regions of lower density
diffusion
the diffusion of water through a semipermeable membrane
osmosis
the movement of substances across a cell membrane without the use of energy by the cell
passive transport
the movement of substances across the cell membrane that requires the cell to use energy
active transport
the process by which a cell membrane surrounds a particle and encloses the particle in a vesicle to bring the particle into the cell
endocytosis
the process in which a cell releases a particle by enclosing the particle in a vesicle that then moves to the cell surface and fuses with the cell membrane
exocytosis
the process by which plants, algae, and some bacteria use sunlight, carbon dioxide, and water to make food
photosynthesis
the process by which cells use oxygen to produce energy from food
cellular respiration
the breakdown of food without the use of oxygen
fermentation
carbon dioxide + water + light energy -> glucose + oxygen
photosynthesis
glucose + oxygen -> carbon dioxide + water + energy (ATP)
cellular respiration
the life cycle of a cell
cell cycle
in a eukaryotic cell, one of the structures in the nucleus that are made up of DNA and protein; in a prokaryotic cell, the main ring of DNA
chromosome
chromosomes that have the same sequence of genes and the same structure
homologous
in eukaryotic cells, a process of cell division that forms two new nuclei, each with the same number of chromosomes
mitosis
the division of the cytoplasm of a cell
cytokinesis
What structures allow small particles to cross cell membranes?
channels
only certain substances can pass through
semipermeable
Why would red blood cells burst if you placed them in pure water?
Red blood cells would burst in pure water because water particles move from outside the cell where particles were dense to inside the cell where water particles were less dense. This movement of water would cause red blood cells to fill up and burst.
What happens when a wilted plant is watered?
Osmosis makes the plant firm again.
Are diffusion and osmosis examples of active or passive transport?
passive transport
What is the difference between passive transport (osmosis) and active transport?
Passive transport occurs without the cell expending energy because particles are moving from an area of high concentration to an area of low concentration.
Active transport requires a cell to use energy to move particles from an area of low concentration into an already crowded are of high concentration.
sacs formed from pieces of cell membrane
vesicles
molecules that absorb light energy
pigments
the main pigment used in photosynthesis which gives plants their green color
chlorophyll
Name two ways animals have to get energy from food. Which way releases more energy?
1- cellular respiration
2- fermentation
** cellular respiration releases more energy from a given food than fermentation does
Respiration means breathing. How is breathing related to cellular respiration?
Breathing supplies the oxygen needed for cellular respiration. Breathing also removes carbon dioxide, which is a waste product of cellular respiration.
What are two kinds of fermentation?
One kind of fermentation produces CO2, and the other kind produces lactic acid.
How are photosynthesis and cellular respiration related?
They are opposite processes. Photosynthesis uses carbon dioxide, water, and energy to produce glucose to store and releases oxygen. Cellular respiration uses glucose and carbon dioxide to produce energy in the form of ATP and releases oxygen and water.
What is the beginning and ending of the cell cycle?
The cell cycle begins when the cell is formed and ends when then cell divides and forms new cells.
cell division in prokaryotic cells is called…
binary fission
Do more complex organisms always have more chromosomes than simpler organisms do?
No. Fruit flies have 8 chromosomes, potatoes have 48, and humans have 46.
Stages of mitosis:
interphase prophase metaphase anaphase telophase cytokinesis
Before mitosis begins, chromosomes are copied. Each chromosome is then 2 chromatids
Interphase
Mitosis begins. The nuclear membrane dissolves. Chromosomes condense into rodlike structures
Prophase
The chromosomes line up along the equator of the cell. Homologous chromosomes pair up.
Metaphase
The chromatids separate and move to opposite sides of the cell.
Anaphase
A nuclear membrane forms around each set of chromosomes, and the chromosomes unwind. Mitosis is complete.
Telophase
In cells that lack a cell wall, the cell pinches in two. In cells that have a cell wall, a cell plate forms between the two new cells.
Cytokinesis
What is the difference between cytokinesis in an animal cell and cytokinesis in a plant cell?
In an animal cell, the cell pinches in two during cytokinesis. In plant cells, a cell plate forms between the two cells during cytokinesis. After the cell splits in two, a cell wall forms where the cell plate was.
`Why is it important for chromosomes to be copied before cell division?
Chromosomes have to be copied before cell division so the two child cells have the same amount of DNA as the parent cell.
