BIONOTESFLASHCARD UP TO 21
What is the function of the nucleus in an animal cell?
It contains all DNA in the animal cell.
What is the nuclear envelope or membrane?
A double phospholipid bilayer that surrounds the nucleus and has pores for RNA to move out.
Where is rRNA transcribed and the subunits of ribosomes assembled?
In the nucleolus.
What is the function of the rough endoplasmic reticulum?
It consists of flattened sacs with many ribosomes and synthesizes proteins.
What does the Golgi complex do?
It modifies and packages proteins for use in other parts of the cell.
What do lysosomes contain and what is their function?
They contain hydrolytic enzymes that digest substances.
What is the smooth endoplasmic reticulum involved in?
Lipid synthesis and detoxification of drugs.
What are peroxisomes?
Vesicles in the cytosol involved in the production and breakdown of hydrogen peroxide.
What is the function of ribosomes?
They make proteins.
What are chromosomes and where are they distinct?
They are part of the nucleus and are distinct during replication.
What is the cytoskeleton?
A network of filaments that determine the structure and motility of the cell.
What are microtubules and their functions?
Larger than microfilaments, rigid hollow tubes made from tubulin, involved in flagella and cilia construction, and spindle apparatus.
What are microfilaments and their functions?
They squeeze the membrane together in phagocytosis and cytokinesis, and provide the contractile force in microvilli and muscle.
What is the function of flagella?
They enable the sperm to move.
Where are cilia found in humans?
In the fallopian tubes and respiratory tract.
What is the role of the centrosome?
It is involved in cell division and microtubules grow from it.
What are centrioles and their functions?
They function in the production of flagella and cilia, but not in microtubule production.
What happens during the G1 phase of the cell life cycle?
The cell splits and grows, usually the longest stage.
What occurs during the S phase?
Energy is used for replicating DNA.
What is the G2 phase?
The cell prepares to divide.
What happens during the M phase?
Meiosis or Mitosis occurs.
What is cytokinesis?
The separation of the cellular cytoplasm due to the constriction of microfilaments about the center of the cell.
What occurs during prophase in mitosis?
Condensation of chromatin into chromosomes, centrioles move to opposite ends of the cell, nucleolus and nucleus disappear, spindle apparatus forms.
What happens during metaphase in mitosis?
Chromosomes align at the equator.
What occurs during anaphase in mitosis?
Sister chromatids split and move toward opposite ends of the cell.
What happens during telophase in mitosis?
The nuclear membrane reforms and the nucleolus reappears.
What is the result of mitosis?
Two identical daughter cells.
What is meiosis?
A double nuclear division which produces four haploid gametes.
What happens during prophase I in meiosis?
Homologous chromosomes line up alongside each other, matching their genes exactly, and may exchange sequences of DNA (crossing over).
What occurs during metaphase I in meiosis?
Homologs move to the metaphase plate but do not separate.
What happens during anaphase I in meiosis?
Homologs separate.
What occurs during telophase I in meiosis?
The nuclear membrane may or may not form. If cytokinesis occurs, the cells are haploid with 23 chromosomes.
What is the sequence of protein synthesis?
DNA -> transcription -> mRNA -> translation -> Protein.
What is the role of tRNA?
Transfers specific amino acids to the growing polypeptide chain during translation.
What does mRNA do?
Conveys genetic information from DNA to the ribosome and is encoded in a sequence of nucleotides.
What is glycolysis?
Anaerobic catabolism of glucose (6C) to pyruvic acid (3C x 2) occurring in the cytoplasm.
What is fermentation?
Glycolysis and reduction of pyruvate, producing ethanol or lactic acid and NAD+.
What is anaerobic respiration?
Absence of O2 results in 2 ATP per mole of glucose.
What is aerobic respiration?
Presence of O2 results in net 36 ATP per mole of glucose.
What is the function of enzymes?
They act as catalysts, lowering the energy of activation and increasing the rate of reaction without being consumed or altered by the reaction.
What are competitive inhibitors?
Compete with the substrate by binding to the active site of the enzyme.
What are noncompetitive inhibitors?
Bind to an enzyme in an area other than the active site, changing the enzyme’s configuration.
What is the difference between eukaryotic and prokaryotic cells?
Eukaryotic cells have a true membrane-bound nucleus, multiple chromosomes, and are usually multicellular, while prokaryotic cells have no true nucleus, one chromosome (plasmid), and are usually unicellular.
What are the key differences between animal and plant cells?
Plant cells have a cell wall, chloroplasts, and large central vacuoles, while animal cells have centrioles and lysosomes.
What is the function of adrenaline/epinephrine?
Hormone and neurotransmitter that regulates heart rate, breathing, and the fight or flight response of the sympathetic nervous system.
What is choline?
A water-soluble essential nutrient.
What is noradrenaline/norepinephrine?
A neurotransmitter released from the sympathetic neurons to affect the heart.
What is acetylcholine?
A neurotransmitter in the autonomic nervous system that acts on the peripheral and central nervous systems. The only neurotransmitter used in the motor division of the somatic nervous system.
What are the key plant hormones for growth of lateral buds?
Auxin, cytokinin, and ethylene.
What is auxin?
A plant hormone that plays a role in the coordination.
