Biology 1 final exam

what are the three components of the cell theory?

1) all living things are made from cells 2) cells are the basic units of life 3) cells come from other cells (biogenesis)

what important molecules does the nucleus contain?

DNA

what is a transgenic organism?

DNA from two sources

interphase is divided into what three phases?

G1 phase, S phase, and G2 phase

how did Pasteur settle the spontaneous generation argument

He put broth into a flask with a neck and showed that when the neck was on, the broth remained clear. when he broke the neck off, the broth became cloudy

what is an enzyme and what is the funtion?

a catalyst that speeds up a chemical reaction

the theory that new organisms come from existing organisms is called what?

biogenesis

manipulation of the genomes of plants, animals, or people with the goal of increasing their health or productivity is called?

biotechnology

the process by which a cell divided into two new daughter cells is called

cell division

what forms midway between the divided nuclei during cytokinesis in plant cells

cell plate

what structures do only plant cells contain?

cell wall, chloroplast, and vacuole

what are most plant cell walls made of?

cellulose

what structrures do only animal cells contain?

centrioles and lysosomes

each pair of chromatids is attached at an area called the?

centromere

at the beginning of cell division, each chromosome consists of two sister

chromatids

the visible material within the nucleus is called

chromatin or chromosomes

cytoplasm

clear fluid inside the cell

the process of allowing cells to reproduce in order to obtain a large number of identical cells is called?

cloning

Golgi body

closely stacked, flattened membrane sacs

pattern of inheritance in which both alleles contribute to the phenotype of the organism

co-dominant

what is homeostasis?

constant conditions that an organism needs to retain

chloroplast

contains clorophyll, a green pigment that traps energy from sunlight

chloroplast

contains inner membranes arranged in stacks of membranous sacs called grana

describe the function of the cell membrane

control what goes in and out of the cell, and protect and support the cell

when a variable is kept unchanged in an experiment, it is said to be

controlled

selective breeding

crossing dissimilar individuals to bring together the best of both organisms

guanine pairs with _

cytosine

phenotype

physical characteristics of an organism

plastids

plant organelles that store starches or lipids or that contain pigments

small circular forms of bacterial DNA are called?

plasmids

what is the condition of having many sets of chromosomes?

polyploidy

what is cytokinesis?

process of cytoplasm dividing into two daughter cells

what is diffusion?

process of particles moving from high concentration to low concentration

what is cell division?

process where cell divides into two daughter cella

what is meiosis?

process where the number of chromosomes per cell is cut in half through separation of homologous chromosomes in a diploid cell

mitochondria

produce a usable form of energy for the cell; uses energy from food to form high energy compunds

in what stage do the centrioles take up positions on opposite sides of the nucleus?

prophase

in what stage do the chromosomes become visible?

prophase

what is ATP used for

storing and releasing energy

what is an organelle?

structures that act like organs in the cell

in what stage does a nuclear envelope reform around each cluster of chromosomes?

telophase

in what stage does the nucleus become visible in each daughter nucleus?

telophase

In science, a hypothesis is useful only if it can be

tested

how did Rudolph Virchow summarize his years of work?

the Cell Theory

what is a cell?

the basic unit of life

inbreeding

the continued breeding of individuals with similar characteristics

Data

the information gathered from observation is called evidence or...

heterozygous

organisms that have two different alleles for the same trait

homozygous

organisms that have two identical alleles for a particular trait

adenine pairs with _ (DNA)

Thymine

thymine pairs with_

adenine

What did german scientist Theodor Schwann conclude?

all animals are made of cells

what did german botanist Matthias Schleiden conclude?

all plants are made of cells

what word describes different forms of a gene?

allele

in what stage do the chromosomes move to the poles?

anaphase

lysosome

digests excess or worn out cell parts, food particles, and invading viruses or bacteria

what word describes a cell that contains two sets of chromosomes?

diploid

what does a pedigree chart show?

family history

cell wall

firm, protective structure that gives the cell its shape in plants, fungi, most bacteria, and protists

ER

folded membrane that forms a network of interconnected compartments in the cytoplasm

what are sex linked genes?

genes on the x chromosome

genotype

genetic makeup of an organism

cytosine pairs with_

guanine

describe the function of the nucleus

holds the DNA for the cell

what are compound light microscopes?

microscopes that allow light to pass through the specimen

what causes a cell to shrink?

hypertonic solution

what causes a cell to swell

hypotonic solution

the period of growth in between cell divisions is called?

interphase

what does not change the shape of a cell?

isotonic solution

what causes osmosis?

isotonic solution, hypotonic solution, and hypertonic solution

what is important about a selectively permeable membrane?

it allows certain things to move across the membrane into the cell

describe the cytoplasm

it is the fluid in the cell

what is the difference between meiosis in male humans and meiosis in female humans?

males have 4 haploid cells, females have 1 haploid cell and 3 polar bodies

in what stage do the chromosomes line up across the center of the cell?

metaphase

when collecting data and doing experiments, what system of measurements do most scientists use?

metric system or SI

the division of the cell nucleus is called _ in body cells, but _ in reproductive cells

mitosis, cytokinesis

golgi body

modifies proteins chemically, then repackages them

the process by which certain bacteria can absorb nitrogen from the atmosphere and convert it to a form that may be used by plants is called?

nitrogen fixation

what is the cytoskeleton?

organelle in eukaryotes that maintain cell shape, move cell parts, and help the cell move

nucleus

organelle that manages cell functions in eukaryotic cells

define prokaryote and give an example

organism whose cell lack nuclei; bacteria

define eukaryote and give an example

organism whose cells contain nuclei; animals, plants, fungi, and protist

vacuole

provides temporary storage of food, enzymes and waste products

a new strand of DNA is formed when DNA fragments from different species of organisms are spliced together is called?

recombinant DNA

what si produced when DNA from two different sources are combined?

recombinant DNA

what is a molecule that cuts DNA molecules at a specific sequence of nucleotides?

restriction enzyme

what is the difference between rough ER and smooth ER

rough ER- covered in ribosomes and makes proteins smooth ER- no ribosomes and makes lipids

what is a hypothesis?

scientific explanation for an observation

what are gametes?

sex cells

describe the function of the cell wall

shape the cell and support and protect the cell

ribosomes

sites of protein synthesis

ribosome

small bumps located on the rough ER

what are variables in an experiment

something that is being tested

a fan like microtubule structure that helps to separate the chromosomes is called?

spindle fibers

the idea that life can arise from nonliving matter is called

spontaneous generation

what is biology?

the study of life

what are chromosomes?

thread like condensed DNA strands

what is a specific characteristic that varies from one individual to another?

trait

condition where and individual has three copies of a chromosome?

trisomy

adenine pairs with_ (RNA)

uracil