chapter 3 Flashcards
power point
What is the basic structural and functional unit of all living organisms?
The cell
The cell is the smallest form of life and all cells come from preexisting cells.
What are the main differences between prokaryotic and eukaryotic cells?
- Prokaryotic cells: No nucleus, no membrane-bound organelles
- Eukaryotic cells: Nucleus, membrane-bound organelles
What is the function of the plasma membrane?
Fluid-mosaic membrane structure that regulates the movement of substances in and out of the cell
The plasma membrane is not solid; its components are free to move laterally.
What are integral and peripheral proteins in the plasma membrane?
- Integral proteins: Embedded in phospholipid bilayer
- Peripheral proteins: On the inside or outside of the membrane
What are the functions of membrane proteins?
- Structural support
- Transport of molecules
- Enzyme regulation
- Receptors for hormones
- Surface antigens
What is the glycocalyx?
Extracellular matrix surrounding animal cells
Functions include cell-to-cell communication and protection from pathogens.
What is the primary function of the bacterial cell wall?
Protects the interior of cells and contributes to the shape of the organism
Different chemical compositions exist among various organisms.
What distinguishes gram-positive bacteria from gram-negative bacteria?
- Gram-positive: Thick peptidoglycan layer, teichoic acids
- Gram-negative: Thin peptidoglycan layer, outer membrane
What are the components of a bacterial flagellum?
- Long filament
- Hook
- Basal body
What are the types of bacterial flagella?
- Monotrichous
- Amphitrichous
- Lophotrichous
- Peritrichous
What is the process of taxis in bacterial movement?
Movement away or toward a stimulus
Rotation of flagella can propel bacteria clockwise or counterclockwise.
What are biofilms?
Collections of surface-associated microbes enclosed by an extracellular matrix
Biofilms can include noncellular materials and are significant in healthcare.
What is the difference between intracellular fluid (ICF) and extracellular fluid (ECF)?
- ICF: High potassium, phosphate; two-thirds of body’s water
- ECF: High sodium, chloride; fluid surrounding cells
What are the mechanisms of passive transport across a cell membrane?
- Diffusion
- Facilitated diffusion
- Osmosis
- Filtration
What is osmosis?
The diffusion of water through a selectively permeable membrane
It goes with the concentration gradient.
What is active transport?
Transport requiring cellular energy, moving substances against their concentration gradient
Examples include pump transport and endocytosis.
What are the two types of endocytosis?
- Phagocytosis (cell eating)
- Pinocytosis (cell drinking)
What is the main role of enzymes in cellular metabolism?
Biological catalysts that speed up chemical reactions without being changed
Most enzymes are proteins with specific active sites.
What are the two main types of metabolic pathways?
- Catabolism: Breaks down large molecules, releases ATP
- Anabolism: Builds large molecules from smaller ones, requires ATP
What is glycolysis?
The conversion of glucose into two molecules of pyruvic acid
It occurs in the cytoplasm and is the first pathway in cellular respiration.
What is the Krebs cycle?
The second pathway in aerobic cellular respiration that processes acetyl-CoA
Produces NADH, FADH2, and GTP.
What is the electron transport chain?
A series of proteins on the mitochondrial cristae that transfer electrons to generate ATP
NADH and FADH2 from the Krebs cycle feed into the ETC.
What is the net production of ATP from one glucose molecule in aerobic respiration?
38 ATPs
This includes 36 from the electron transport chain and 4 from glycolysis.
What type of process is exergonic?
Energy is released during the process.
