LIFE SCI Flashcards
What is the basic unit of life?
Cell
Cells are the foundational building blocks of all living organisms.
Define tissues in biological organization.
Groups of cells with similar structure and function.
What are organs?
Structures made up of tissues working together to perform specific functions.
What defines organ systems?
Groups of organs working together to carry out a function.
What is the composition of organisms?
Made up of one or more organ systems.
What are the three main tenets of modern cell theory?
- The cell is the smallest living unit in all organisms.
- All living things are composed of cells.
- All cells come from pre-existing cells.
What are prokaryotes?
Found in bacteria and archaea; no nucleus and no membrane-bound organelles.
What defines eukaryotes?
Found in fungi, protists, animals, and plants; have a nucleus and membrane-bound organelles.
What is the function of the cell membrane?
Separates the interior of the cell from the external environment and exhibits selective permeability.
What is cytoplasm?
A fluid that fills the cell.
What is the role of ribosomes?
The site of protein synthesis in the cell.
What is the nucleus?
The control center of eukaryotic cells; contains DNA.
What is the function of the endoplasmic reticulum (ER)?
processing molecules and folding proteins.
- Rough ER:
o Covered in ribosomes.
o In protein synthesis and transport. - Smooth ER:
o Produces lipids and hormones.
o Detoxifies chemicals and stores calcium.
What are the two types of endoplasmic reticulum?
- Rough ER: Covered in ribosomes and facilitates protein synthesis and transport.
- Smooth ER: Produces lipids and hormones, detoxifies chemicals and stores calcium.
What is the function of the Golgi apparatus?
Packages and processes proteins and lipids for export.
What is the primary function of mitochondria?
Generates most of the cell’s energy through biochemical reactions and produces ATP.
What is the role of chloroplasts in plant cells?
The site of photosynthesis; converts sunlight into chemical energy.
What do lysosomes contain?
Digestive enzymes to break down waste and worn-out cell parts.
What are vacuoles and their functions in animals and plants?
- In animals: Sequester waste products.
- In plants: Maintain water balance.
What is mitosis?
A type of cell division that produces two identical daughter cells.
What is meiosis?
A type of cell division that produces four daughter cells with half the chromosomes of the parent cell.
Define heredity.
The passing of physical or mental characteristics from one generation to the next.
What is DNA?
The self-replicating material present in all living organisms; the main constituent of chromosomes.
What is the structure of DNA?
Composed of phosphate, deoxyribose (sugar), and nitrogenous bases forming a nucleotide.
What is the base pairing in DNA?
- Adenine ↔ Thymine
- Cytosine ↔ Guanine
What are genes?
Units of heredity transferred from parents to offspring, determining characteristics.
What are the types of RNA?
- mRNA (Messenger RNA): Carries genetic information from DNA to the ribosome to make proteins.
- rRNA (Ribosomal RNA): Forms the core of ribosomes, the site of protein synthesis.
- tRNA (Transfer RNA): Acts as an adaptor molecule that decodes mRNA into proteins by carrying amino acids.
What is the process of transcription?
Creating an RNA copy of a gene’s DNA sequence.
- Occurs in the nucleus.
o RNA Polymerase binds to DNA and creates a complementary mRNA strand.
o After transcription, mRNA undergoes editing and is transported to the cytoplasm.
o In the cytoplasm, mRNA interacts with ribosomes (made of rRNA) to initiate protein synthesis.
What is translation?
Converting mRNA sequences into amino acid chains (proteins).
* Occurs in the cytoplasm.
o tRNA molecules carry amino acids and match their anticodons to the mRNA codons in groups of three bases at a time (codons).
o Ribosomes facilitate the process, assembling amino acids into proteins based on the mRNA sequence.
Define Mendel’s Law of Inheritance.
Fundamental principles explaining how traits are inherited from parents to offspring.
What is an allele?
One of two or more alternative forms of a gene found at the same position on a chromosome.
What does genotype refer to?
The two alleles present at a specific locus in the genome.
What is a homozygous dominant genotype?
Both alleles are the same and dominant (e.g., AA).
What is a homozygous recessive genotype?
Both alleles are the same and recessive (e.g., aa).
What is a heterozygous genotype?
Two different alleles, one being dominant and the other recessive (e.g., Aa).
Define phenotype.
The observable traits or characteristics of an individual.
What is a dihybrid cross?
A genetic cross involving two observed traits, each controlled by distinct genes.
What is non-Mendelian inheritance?
A form of gene interaction where both alleles are partially expressed.
What is incomplete dominance?
The heterozygous phenotype is an intermediate blend of the two homozygous phenotypes.
Define codominance.
A type of inheritance where both alleles contribute equally and are expressed in the phenotype.
What are carbohydrates?
Biomolecules consisting of carbon, hydrogen, and oxygen atoms.
Define lipids.
A diverse group of organic compounds that are hydrophobic.
What are proteins?
Large biomolecules made of one or more long chains of amino acids.
What are nucleic acids?
Large biomolecules found in all cells and viruses that store and transmit genetic information.
What is a monomer?
A building block molecule that can react with other monomers to form larger polymer chains.
What are pathogenic microorganisms?
Bacteria, viruses, and other types of germs that cause disease.
What is the difference between infectious and non-infectious diseases?
- Infectious: Spread from one person to another.
- Non-Infectious: Cannot be spread from one person to another.
Define magnification in microscopy.
The action or process of making an object appear larger.
What is resolution in microscopy?
The ability to distinguish fine details of a specimen.
Perform a Dihybrid Cross
4x4 Punnett Square
Write Gamete Combinations
FOIL
Merge the Alleles in the Punnett Square
- Virulence:
Refers to how severe or harmful a disease is caused by a pathogen.
Bacteria TYPES
o Gram Positive: Thin cell wall.
o Gram Negative: Thick cell wall.
. Modes of Transmission
- Direct Transmission: Spread through direct contact, such as oral secretions, blood, or infectious fluids.
- Droplet Transmission: Spread through sneezing or coughing, releasing droplets that contain infectious agents.
- Indirect Transmission: Spread through airborne particles, such as dust, carrying infectious agents.
virus diseases
Respiratory Tract - common cold,
influenza, COVID
* Gl Tract - rotavirus, mumps
* Systemic - chicken pox, HIV
* Skin - HPV
* Central Nervous System - Polio
bacteria diseases
Chlamydia
* Community-Acquired Pneumonia
(Mycoplasma)
* Streptococcus - Strep Throat
* Staphylococcus Aureus - Skin
Infections
* Tetanus
Fungi diseases
Mycosis
* Skin - Tinea (Ringworm, Athletes
Foot)
* Mucous Membranes - Thrush
* Lungs and Blood
Protozoa diseases
malaria
giardiasis
animals diseases
Helminths cause Gl Disease
* Ectoparasites causes Skin
Inflammation and Allergic
Reactions
* Ticks - Lyme Disease
scientific reasoning
drawing conclusions
variable: A FACTOR, CONDITION, OR ITEM THAT CAN BE CHANGED, CONTROLLED OR MEASURED IN AN
EXPERIMENT
Independent: “The cause” (thing u change)
dependent: “The effect” (thing u measure)
controlled: conditions maintained
casual relationships
THE CONNECTION BETWEEN TWO VARIABLES WHERE ONE VARIABLE INFLUENCES OR
CAUSES A CHANGE IN THE OTHER VARIABLE
CAUSE: WHAT CAUSES THE OUTCOME OF EFFECT
EFFECT: OUTCOME
Scientific method:
THE PROCESS OF OBSERVING, ASKING QUESTIONS, AND SEEKING ANSWERS THROUGH
TESTS AND EXPERIMENTS TO ESTABLISH FACTS
observation, research, hypothesis, experiment, conclusion, share results,
