Biology I semester exam review

Biology I Semester Exam

Qualitative

observations based on qualities

Quantitative

observations based on quantities

Inference

Non-observed, Inferred

Scientific Method

Scientific investagation involving observation and experimentation to demonstrate to demonstrate truth or falseness of hypothesis, and results validate or modify hypothesis.

Hypothesis

a tentative explanation that a scientist proposes for a specific phenomenon that has been observed.

Independent/Dependent Variables

Dependant depends on the independent variable, while the independent doesn't depend on a variable

Pseudoscientific

Not based on science ( "false science") ex: aliens, religion, and beliefs

Do's and Don'ts of proper experimenting

- goggles must be worn when glass, chemicals, or heat being used. - follow disposal procedures.-use gloves for very hot/cold materials.-when needed/required: ventilation.

Constants

contrasts variables in an experiment.

Experimental/Control groups

a group of subjects that are exposed to the variable of a controlled experiment.

Cell Theory

The theory that all living things are composed of cells (1), all cells come from other cells (2), and cells are the basic unit of living things (3).

Scientist contributing to cell theory development

Hooke, Schleiden, Schwann, Virchow.

Eukaryotic Cells

a type of cell that has a membrane-enclosed nucleus and other membrane-enclosed organelles. All organisms except bacteria and archaea are composed of eukaryotic cells.

Prokaryotic Cells

a type of cell lacking a membrane-enclosed nucleus and other membrane-enclosed organelles; found only in the domains of bacteria and archaea.

Cell membrane

cell's outer membrane made up of two layers (phospholipids and proteins), it separates cell from outside environment, and regulates what enters and exit's the cell.

Cell wall

a membrane of the cell that forms external to the cell membrane, main role is to give cells protection.

Ribosome

a particle composed of protein , serves as site of protein synthesis.

Chloroplasts

chlorophyll containing plastid found within the cells pf plants and photosynthetic-eukaryotes.

Cytoskeleton

internal framework of a cell, controls cells shape, maintains organization, and in cell movement

Golgi body

structure in cytoplasm of animal cells receives proteins from endoplasmic reticulum and packages and distributes them to other parts of the cell.

Lysosome

used for digestion and removal or excess or worn out organelles, food particles, and bacteria.

Mitochondria

in the cytoplasm of eukaryotic cells, they act as the site for production of high-energy compounds.

Nucleus

The central part around which other parts are grouped. Maintains integrity of DNA, and control cellular activities.

Vacuole

found in cytoplasm of a cell, function is digestion.

Cytoplasm

found in eukaryotic cells, everything enclosed by the cell membrane.

Selective permeability

function of plasma membrane that is essential to maintain homeostasis by letting some things in and not others.

Fluid mosaic model:

a model that describes the structural features of biological membranes.

Diffusion

the passive movement of molecules or particles along a concentration gradient or from the regions of higher to lower concentration.

Osmosis

movement of water molecules threw a semi permeable membrane from an area of low solute concentration to an area of high solute concentration.

Facilitated diffusion

transport of substances across a membrane from an area of higher concentration to an area of lower concentration. Energy is not required.

Active transport

a kind of transport, opposite of diffusion. Movement from and area of lower concentration to an area of higher concentration.

Bulk Transport

transport of large materials.

Hypotonic

solution with a lower concentration of solutes compared to another.(cell will swell)

Hypertonic

solution with a higher concentration of solutes compared to another (cell will shrink)

Isotonic

two solutions have an equal concentration (cell will stay the same)

ATP

releases energy when phosphate bonds are broken, the energy is used for many metabolic processes. ATP is produced via cellular respiration in the mitochondria and photosynthesis in chloroplasts.

Autotrophs

(producers) an organism capable of making organic molecules from inorganic sources

Heterotrophs

(consumers) an organism that is unable to synthesize its own organic molecules

Enzymes

Enzymes are a chemical produced to speed up a specific chemical reaction. They are made of RNA. Enzymes are usually a protein molecule with amino acids that fold to produce a specific 3-D structure.

Photosynthesis

Photosynthesis is the synthesis of a complex organic material, using c02, water, and light energy. It enables photosynthetic organisms to create their own food directly from inorganic compounds. Equation: 6CO2+12H2O+energy=C6H12O6+6O2+6H2O.

Respiration

Respiration is a process that takes place within a cell in which energy is harvested from organic substances and stored as ATP for use in energy-requiring activities of the cell. Equation: C6HA12O6 + 6O2 → 6CO2 + 6H2O δHc -2880 kJ.

Mitosis

Mitosis is the process where a single cell divides resulting in generally two identical cells, each cell containing the same number of chromosomes and genetic content of the original cell.

Interphase

consists of G1, S, and G2. During interphase the chromosomes in a cell are duplicated. Stage cells spend majority of time in.

Prophase

first stage of mitosis, during this stage chromosomes condense and become visible.

Metaphase

the stage where condensed chromosomes have aligned along the metaphase plate.

Anaphase

the stage with the separation of sister chromatids followed by the movement towards the pole of the spindle.

Telophase

the final stage of mitosis where chromosome separation is completed. Chromosomes move towards opposite ends of nuclear spindle.

Overal Mitosis

Chromosomes condense along the center of the nucleus and pair with their homologues during crossing over. Next pairs of chromosomes separate and move to opposite ends of the cell, cell divides and creates two new cells

Cytokinesis

the division of the cytoplasm and plasma membrane, each having its own nucleus and cytoplasm surrounded by a plasma membrane.

Chromosomes

structure within the cell that bears genetic material as a threadlike strand of DNA bonded to various proteins in the nucleus of various eukaryotic cells. Or a circular strand of DNA in the cytoplasm of prokaryotes, or in mito. and chlor. Of certain eukaryotes.

Chromatin

a complex of nucleic acids which condenses to form chromosome during cell division.

Sister chromatids

two identical strands joined by a common centromere.

Centriole

a self-replicating organelle located in the cytoplasm near the nucleus in cells of most animals.

Parent and Daughter cells

parent cell is the cell that divides to give rise to two daughter cells. In mitosis the daughter cells have same genetic content as parent.

Binary fission

common among prokaryotes, cell divides giving rise to two cells, each having potential to grow to the size of the original cell.

Budding

the formation of an outgrowth of an organism, and is capable of developing into a new individual.

Fragmentation

parent organism breaks into fragments, each capable of growing independently into a new organism.

Vegetative reproduction

plants where new individuals emerge from the vegetative parts of plants.

Cancer

cells that divide and reproduce abnormally with uncontrolled growth, cell can break away and travel to other parts of the body and set up another site.(metastasize)

Malignant

cancer cells that will metastasize.

Benign

a tumor that will not metastasize.

Meiosis

A form of cell division happening in sexual reproducing organisms by which two consecutive nuclear divisions occur without the chromosomal replication in between, leading to the production of haploid gametes(sex cells), each containing one pair of every homologous chromosome. Reduces the original number of chromosomes in half, the 4 haploid cells may develop into gametes.

Interphase(meiosis)

chromosomes in a cell are duplicated

Meiosis 1

chromosome condenses along the center of the nucleus and pair with their homologues during crossing over. Then pairs of chromosomes separate and move to opposite end of the cell. The cell divides, producing two cells.

Meiosis 2

both of the two cells divide into two cells each containing one of every decoupled chromosome's sister traits. Produces 4 genetically different haploid cells.

Numerical

occurs when an individual is missing either a chromosome from a pair (monosomy), or has more than two chromosomes of a pair (trisomy).

Structural

occurs when chromosome's structure is altered. Deletions, duplications, translocations, and inversions.

Crossing-over

a process occurring during meiosis where two chromosomes pair up and exchange segments of their genetic material.

Nondisjunction

the failure of sister chromatids to separate during and after mitosis. (same for meiosis)

Karyotype

the characterization of the chromosome complement of a species.

Trait:

characteristics of a an organism that are expressed by genes and/or influenced by the environment

Gene

the fundamental, physical, and functional unit of hereditary.

Alleles

one member of a pair of genes occupying a specific spot on a chromosome that controls the same trait.

Genotype

the entire set of genes in an organism

Phenotype

the physical appearance or biochemical characteristic of an organism as a result of the interaction of its genotype and the environment.

Homozygous

individual containing two copies of the same allele for a particular trait located at similar positions on paired chromosomes.

Heterozygous

an individual containing two different alleles for a particular trait.

Purebred

unmixed lineage

Hybrid

any mixed origin or composition, or the combination of two or more different things.

Dominant

an allele or a gene that is expressed in an organism's phenotype, masking the effect of the recessive allele or gene when present.

Recessive

a gene or allele whose phenotypic expression is masked by a dominant gene or allele.

Codominance

a condition in which alleles of a gene pair in a heterozygote are fully expressed, resulting in an offspring with a phenotype that is not dominant or recessive.

Incomplete dominance

occurring in heterozygous in which dominant gene or allele is only partially expressed.

Sex-linked

pertaining to a gene located in the sex chromosome.

Multiple alleles

the existence of several known alleles of a gene.

Carriers

an organism possessing a recessive gene for a trait, not expressing the trait.

The law of segregation

states that the alleles governing a trait are separated during the creation of gametes.

The law of independent assortment

states that the genes controlling different traits are distributed separately from each other during meiosis.