Week 5A Flashcards
What are the major cell structures and organelles, and what functions do they serve?
Major structures include the nucleus (contains DNA), mitochondria (energy production), and ribosomes (protein synthesis).
What is the role of antibodies in the immune response?
Antibodies are proteins that identify and neutralize foreign invaders or antigens.
What are the four primary elements that form protoplasm?
Carbon, hydrogen, oxygen, and nitrogen.
What is the role of repair enzymes in cellular damage recovery?
Repair enzymes mend damaged molecules, aiding in the recovery from radiation-induced damage.
What are the functions of DNA?
DNA carries genetic information necessary for cell replication and regulates cellular activity and protein synthesis.
What role do water and mineral salts play in cell function?
Water transports substances in and out of cells, while mineral salts maintain cell osmosis and nerve function.
What types of RNA exist, and what are their locations and functions?
Types include mRNA (in cytoplasm, directs protein synthesis), rRNA (in ribosomes, forms proteins), and tRNA (brings amino acids to ribosomes).
What is the process of mitosis?
Mitosis is the process of cell division resulting in two identical daughter cells, involving stages: prophase, metaphase, anaphase, and telophase.
What is the molecular structure of DNA?
DNA consists of two long sugar-phosphate chains twisted in a double-helix, linked by nitrogenous bases.
How do hormones affect body functions?
Hormones are chemical messengers regulating processes such as growth, metabolism, and mood.
How does the structure of DNA enable its function as the genetic material?
DNAs double-helix structure allows it to store and transmit genetic information via sequences of nitrogenous bases.
How does meiosis differ from mitosis?
Meiosis reduces chromosome number by half, resulting in four genetically diverse gametes, while mitosis produces two identical cells.
What are the major organic and inorganic substances found in the cell?
Organic compounds and inorganic compounds such as water and mineral salts.
What is the role of proteins in cell structure and function?
Proteins provide structural support, facilitate biochemical reactions as enzymes, and regulate cellular processes.
How do cells perform diverse functions in the body?
Cells specialize in various tasks, adapting their structures and processes to meet specific physiological needs.
How do organic compounds differ from inorganic compounds?
Organic compounds contain carbon and are usually associated with living organisms, while inorganic compounds do not primarily contain carbon.
How do you define a chromosome?
A chromosome is a structure made of DNA and proteins that contains genetic information.
What are the key components of nucleic acids?
Nucleic acids are composed of nucleotides, which include a sugar, phosphate group, and nitrogenous base.
How do structural and enzymatic proteins differ in function?
Structural proteins provide shape and support, while enzymatic proteins act as catalysts to speed up biochemical reactions.
What is protoplasm and its significance in living organisms?
Protoplasm is the living substance of cells, essential for metabolism, growth, and reproduction.
What are the structural roles of lipids in the cell?
Lipids form cell membranes and provide insulation and protection for vital organs.
What are amino acids and their significance in protein synthesis?
Amino acids are the building blocks of proteins; their arrangement dictates protein structure and function.
What is a gene, and how does it relate to DNA?
A gene is a segment of DNA that codes for a specific protein, influencing traits and functions.
How do carbohydrates serve as a source of energy for the cell?
Carbohydrates function as short-term energy stores, primarily metabolized for fuel.
How do proteins contribute to growth and tissue repair?
Proteins are essential for constructing new tissues and repairing damaged structures.
What are the functions of water within and outside the cell?
Inside, water is a medium for reactions; outside, it transports materials, maintains body temperature, lubricates systems, and protects organs.
What is the main purpose of genes within chromosomes?
Genes direct cytoplasmic activity, control cell growth and development, and transmit hereditary information.
What result does meiosis produce in terms of chromosome number?
Meiosis results in four daughter cells, each with 23 chromosomes.
What are the main components of a normal human cell?
The main components are the cell membrane, cytoplasm, cytoplasmic organelles, and nucleus.
What are the distinct phases of the cellular life cycle?
The phases are M (mitosis), G1 (growth), S (DNA synthesis), and G2 (preparation for mitosis).
What is the process of mitosis and why is it important?
Mitosis is the process where a cell divides to form two identical daughter cells, important for growth and repair.
How many types of tRNA are present in a human cell?
There are at least 22 types of tRNA, one for each amino acid.
What is the outcome of the telophase stage of mitosis?
In telophase, the cytoplasm divides, and the nuclear membrane reappears, resulting in two identical cells.
Describe the structure of chromosomes.
Chromosomes are tiny rod-shaped bodies composed of protein and DNA, visible only in dividing cells.
What is the primary function of ribosomal RNA (rRNA)?
rRNA assists in linking mRNA to the ribosome to facilitate protein synthesis.
How do mineral salts contribute to the cells osmotic pressure?
Mineral salts help maintain the correct water proportion in cells, crucial for osmotic pressure and cell function.
How does meiosis differ from mitosis?
Meiosis reduces chromosome number by half, occurring in germ cells, while mitosis creates identical somatic cells.
Why is water considered essential for cellular functions?
Water is crucial for chemical reactions, acts as a solvent, and helps regulate the concentration of substances in cells.
Describe what occurs during prophase.
In prophase, the nuclear membrane dissolves, and spindle structures form, anchored by centrioles.
What are inorganic compounds, and how do they differ from organic compounds?
Inorganic compounds do not contain carbon and are found as acids, bases, and salts; organic compounds do contain carbon.
What are the stages of meiosis?
Meiosis occurs in two stages: a mitosis-like division and a division without replication, producing four cells.
How are chromosomes arranged during metaphase?
During metaphase, paired chromosomes line up along the central axis of the spindle.
What is the structure and function of messenger RNA (mRNA)?
mRNA resembles one half of a DNA molecule and serves as a template for protein synthesis.
What happens to chromosomes during anaphase?
In anaphase, the paired chromosomes separate and move towards opposite poles of the cell.
What role does transfer RNA (tRNA) play in protein synthesis?
tRNA receives the genetic code from mRNA, combines with amino acids, and delivers them to ribosomes to form proteins.
What is the human genome and how is it structured?
The human genome is the total amount of genetic material (DNA) in chromosomes, with about 30,000 genes mapped in roughly 2.9 billion base pairs.
How does mRNA differ from DNA in terms of composition?
mRNA contains uracil (U) instead of thymine (T), and is a single strand rather than a double helix.
How many chromosomes do normal human somatic cells contain?
Normal human somatic cells contain 46 chromosomes, arranged in 23 pairs.
How many base pairs are estimated to be in the human genome?
The human genome has approximately 2.9 billion base pairs.
What are the four subphases of mitosis?
The four subphases are prophase, metaphase, anaphase, and telophase.
