BIOL 1100 UNIT 03 (Ch 08, 10, 11, 12, 13) Flashcards
autotroph
organism that produces organic molecules from small inorganic compounds
heterotroph
organism that consumes organic substances or other organisms for food
chloroplast
organelle in which photosynthesis takes place
thylakoid
disc-shaped, membrane-bound structure inside a chloroplast where the light-dependent reactions of photosynthesis take place;
(stacks of thylakoids are called grana)
grana
stack of thylakoids located inside a chloroplast
stroma
fluid-filled space surrounding the grana inside a chloroplast where the light-independent reactions of photosynthesis take place
stomata
opening that regulates gas exchange and water evaporation between leaves and the environment, typically situated on the underside of leaves
what are the reactants of photosynthesis?
6CO2 + 6H20
what are the reactants of aerobic respiration
glucose and oxygen
what are the products of photosynthesis?
C6H12O6 + 6O2
what are the products of aerobic respiration?
CO2, H20, ATP
What is the ultimate source of our food and oxygen?
the sun
sexual reproduction
mixing of genetic material from two individuals to produce genetically unique offspring
asexual reproduction
form of reproduction that produces offspring that are genetically identical to the parent
sister chromatids
identical copies of a chromosome that are joined at the centromere and are created during DNA replication
what holds sister chromatids together?
cohesin
What phase does most eukaryotes spend the majority of their life cycle in?
interphase
Benign
a growth that is not cancerous and does not invade nearby tissue or spread to other parts of the body
Malignant
a growth that is uncontrolled cancerous cells and can spread to nearby tissues or throughout the body
Cell cycle
ordered series of events involving cell growth and cell division that produces two new daughter cells
Interphase
period of the cell cycle leading up to mitosis; includes G1, S, and G2 phases (the interim period between two consecutive cell divisions)
g1 phase
(also, first gap) first phase of interphase centered on cell growth during mitosis
g2 phase
(also, second gap) third phase of interphase during which the cell undergoes final preparations for mitosis
S phase
synthesis (of DNA), stage of interphase during which DNA replication occurs
mitosis (with stages)
(also, karyokinesis: mitotic nuclear division) period of the cell cycle during which the duplicated chromosomes are separated into identical nuclei;
includes prophase, prometaphase, metaphase, anaphase, and telophase
prophase
stage of mitosis during which chromosomes condense and the mitotic spindle begins to form
prometaphase
stage of mitosis during which the nuclear membrane breaks down and mitotic spindle fibers attach to kinetochores
metaphase
stage of mitosis during which chromosomes are aligned at the metaphase plate
anaphase
stage of mitosis during which sister chromatids are separated from each other
telophase
stage of mitosis during which chromosomes arrive at opposite poles, decondense, and are surrounded by a new nuclear envelope
cytokinesis
division of the cytoplasm following mitosis that forms two daughter cells.
condensin vs cohesin
condensin: proteins that help sister chromatids coil during prophase
cohesin: proteins that form a complex that seals sister chromatids together
autosome
any of the non-sex chromosomes
sex chromosome
chromosomes that determine a person’s sex
Haploid
cell, nucleus, or organism containing one set of chromosomes (n)
Diploid
cell, nucleus, or organism containing two sets of chromosomes (2n)
Somatic cell
all the cells of a multicellular organism except the gametes or reproductive cells
Gametes
haploid reproductive cell or sex cell (sperm, pollen grain, or egg)
Zygote
a fertilized egg (embryo)
Karyotyping
a method to identify traits characterized by chromosomal abnormalities from a single cell.
Homologue
a gene or biological feature that is descended from a common ancestor.
(The term “homolog” can also refer to a pair of chromosomes that separate during the first meiotic division.)
(Homologous chromosomes are matching pairs of chromosomes inherited from each parent.)
locus
position of a gene on a chromosome
What is Mendel’s typical experiment
cross-breeding pea plants with distinct, contrasting traits (like tall vs. short), allowing them to self-fertilize over multiple generations, and carefully counting the resulting offspring to observe how traits were inherited, revealing patterns of dominant and recessive alleles (P generation: The initial parental plants with contrasting traits. F1 generation: Offspring from the P generation cross, usually displaying only one dominant trait. F2 generation: Offspring from self-fertilizing the F1 generation, where the recessive trait reappears in a predictable ratio.)
Dominant
a variant of a gene that expresses itself more strongly than other versions of the gene
Recessive
trait that appears “latent” or non-expressed when the individual also carries a dominant trait for that same characteristic; when present as two identical copies, the recessive trait is expressed
Allele
gene variations that arise by mutation and exist at the same relative locations on homologous chromosomes
Gene
physical and functional unit of heredity, a sequence of DNA that codes for a protein.
What is complete dominance inheritance
a genetic condition where one allele, completely masks the effect of another (recessive) allele.
Carrier (and chances of passing on a disorder)
a person who has a mutated gene that causes a disease or trait but does not exhibit symptoms of the disease or trait;
50% chance that the child will be a carrier; 25% chance that the child will develop the disease if both parents are carriers
complete dominant
a type of inheritance pattern in genetics where one allele is completely dominant over another, masking the recessive allele (ex: specific hair color, skin pigment, and brown eyes. Not all examples of complete dominance are common though. Dwarfism also shows complete dominance, but it is rare.)
codominance
a type of inheritance where two different versions of a gene, or alleles, are expressed equally in an individual, resulting in both traits appearing.
(ex: a red roan cow and a white roan cow produce a baby that is both red and white)
(ex: A classic example of codominance is a person with AB blood type, where both the A allele and the B allele are expressed equally)
incomplete dominant
neither allele is dominant so the two alleles combine to create a new phenotype.
(ex: when red and white snapdragon flowers are crossed, resulting in offspring with pink flowers; in this case, neither the red nor white allele is completely dominant, leading to a blended phenotype of pink in the heterozygous offspring)
polygenic
phenotypic characteristic caused by two or more genes
pleiotropy
a genetic phenomenon where a single gene or mutation affects multiple traits; Pleiotropy occurs when a DNA variant influences more than one trait. (An example of pleiotropy in humans is phenylketonuria (PKU), a disorder caused by a deficiency in the enzyme phenylalanine hydroxylase. This deficiency can lead to multiple phenotypes, including mental retardation, eczema, and pigment defects; also sickle cell, albinism)
Male sex chromosome
Y
Female sex chromosome
X
why are sex-linked conditions tend to be more common among men than among women
Sex-linked conditions are more prevalent in men than women because males only have one X chromosome, so if a recessive gene for a sex-linked condition is present on that X chromosome, it will be expressed, while females, having two X chromosomes, can usually carry a recessive gene without showing the condition as they have a normal copy on the other X chromosome to compensate
karyotype
an individual’s chromosome number and appearance;
includes the size, banding patterns, and centromere position; a genetic test that examines the size, shape, and number of chromosomes in a sample of cells from the body. It can help identify genetic problems that cause disorders or diseases, such as birth defects, cancer, or infertility.