BIOL 1100 UNIT 03 (Ch 08, 10, 11, 12, 13)

Question 1

autotroph

Answer 1

organism that produces organic molecules from small inorganic compounds

Question 2

heterotroph

Answer 2

organism that consumes organic substances or other organisms for food

Question 3

chloroplast

Answer 3

organelle in which photosynthesis takes place

Question 4

thylakoid

Answer 4

disc-shaped, membrane-bound structure inside a chloroplast where the light-dependent reactions of photosynthesis take place;

(stacks of thylakoids are called grana)

Question 5

grana

Answer 5

stack of thylakoids located inside a chloroplast

Question 6

stroma

Answer 6

fluid-filled space surrounding the grana inside a chloroplast where the light-independent reactions of photosynthesis take place

Question 7

stomata

Answer 7

opening that regulates gas exchange and water evaporation between leaves and the environment, typically situated on the underside of leaves

Question 8

what are the reactants of photosynthesis?

Answer 8

6CO2 + 6H20

Question 9

what are the reactants of aerobic respiration

Answer 9

glucose and oxygen

Question 10

what are the products of photosynthesis?

Answer 10

C6H12O6 + 6O2

Question 11

what are the products of aerobic respiration?

Answer 11

CO2, H20, ATP

Question 12

What is the ultimate source of our food and oxygen?

Answer 12

the sun

Question 13

sexual reproduction

Answer 13

mixing of genetic material from two individuals to produce genetically unique offspring

Question 14

asexual reproduction

Answer 14

form of reproduction that produces offspring that are genetically identical to the parent

Question 15

sister chromatids

Answer 15

identical copies of a chromosome that are joined at the centromere and are created during DNA replication

Question 16

what holds sister chromatids together?

Answer 16

cohesin

Question 17

What phase does most eukaryotes spend the majority of their life cycle in?

Answer 17

interphase

Question 18

Benign

Answer 18

a growth that is not cancerous and does not invade nearby tissue or spread to other parts of the body

Question 19

Malignant

Answer 19

a growth that is uncontrolled cancerous cells and can spread to nearby tissues or throughout the body

Question 20

Cell cycle

Answer 20

ordered series of events involving cell growth and cell division that produces two new daughter cells

Question 21

Interphase

Answer 21

period of the cell cycle leading up to mitosis; includes G1, S, and G2 phases (the interim period between two consecutive cell divisions)

Question 22

g1 phase

Answer 22

(also, first gap) first phase of interphase centered on cell growth during mitosis

Question 23

g2 phase

Answer 23

(also, second gap) third phase of interphase during which the cell undergoes final preparations for mitosis

Question 24

S phase

Answer 24

synthesis (of DNA), stage of interphase during which DNA replication occurs

Question 25

mitosis (with stages)

Answer 25

(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

Question 26

prophase

Answer 26

stage of mitosis during which chromosomes condense and the mitotic spindle begins to form

Question 27

prometaphase

Answer 27

stage of mitosis during which the **nuclear membrane breaks down** and **mitotic spindle fibers attach to kinetochores**

Question 28

metaphase

Answer 28

stage of mitosis during which chromosomes are aligned at the metaphase plate

Question 29

anaphase

Answer 29

stage of mitosis during which sister chromatids are separated from each other

Question 30

telophase

Answer 30

stage of mitosis during which **chromosomes** arrive at **opposite poles**, **decondense**, and are surrounded by a new **nuclear envelope**

Question 31

cytokinesis

Answer 31

division of the cytoplasm following mitosis that forms two daughter cells.

Question 32

condensin vs cohesin

Answer 32

condensin: proteins that help sister chromatids coil during prophase cohesin: proteins that form a complex that seals sister chromatids together

Question 33

autosome

Answer 33

any of the non-sex chromosomes

Question 34

sex chromosome

Answer 34

chromosomes that determine a person's sex

Question 35

Haploid

Answer 35

cell, nucleus, or organism containing one set of chromosomes (n)

Question 36

Diploid

Answer 36

cell, nucleus, or organism containing two sets of chromosomes (2n)

Question 37

Somatic cell

Answer 37

all the cells of a multicellular organism except the gametes or reproductive cells

Question 38

Gametes

Answer 38

**haploid** reproductive cell or sex cell (sperm, pollen grain, or egg)

Question 39

Zygote

Answer 39

a fertilized egg (embryo)

Question 40

Karyotyping

Answer 40

a method to **identify traits** characterized by **chromosomal abnormalities** from a **single cell**.

Question 41

Homologue

Answer 41

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.)

Question 42

locus

Answer 42

position of a gene on a chromosome

Question 43

What is Mendel's typical experiment

Answer 43

**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.)

Question 44

Dominant

Answer 44

a variant of a gene that expresses itself more strongly than other versions of the gene

Question 45

Recessive

Answer 45

**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**

Question 46

Allele

Answer 46

gene **variations** that arise by **mutation** and exist at the **same relative locations** on homologous chromosomes

Question 47

Gene

Answer 47

physical and functional unit of heredity, a sequence of DNA that codes for a protein.

Question 48

What is complete dominance inheritance

Answer 48

a genetic condition where one allele, completely masks the effect of another (recessive) allele.

Question 49

Carrier (and chances of passing on a disorder)

Answer 49

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

Question 50

complete dominant

Answer 50

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.)

Question 51

codominance

Answer 51

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)

Question 52

incomplete dominant

Answer 52

**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)

Question 53

polygenic

Answer 53

**phenotypic characteristic** caused by two or more genes

Question 54

pleiotropy

Answer 54

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)

Question 55

Male sex chromosome

Answer 55

Y

Question 56

Female sex chromosome

Answer 56

X

Question 57

why are sex-linked conditions tend to be more common among men than among women

Answer 57

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

Question 58

karyotype

Answer 58

**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.