Biology Test Review: C3, C4, CAM Plants and Mitosis

C3 Plants

A plant that uses the Calvin cycle for the initial steps that incorporate CO2 into organic material, forming a three-carbon compound as the first stable intermediate.

photorespiration

A metabolic pathway that consumes oxygen, releases carbon dioxide, generates no ATP, and decreases photosynthetic output; generally occurs on hot, dry, bright days, when stomata close and the oxygen concentration in the leaf exceeds that of carbon dioxide.

CAM Plants

plants close their stomata during the day, collect CO2 at night, and store the CO2 in the form of acids until it is needed during the day for photosynthesis

chromosomes

a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.

asexual reproduction

Process by which a single parent reproduces by itself

clone

An organism that is genetically identical to the organism from which it was produced

sexual reproduction

A reproductive process that involves two parents that combine their genetic material to produce a new organism, which differs from both parents

binary fission

A form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size

sister chromatids

Identical copies of a chromosome; full sets of these are created during the S subphase of interphase.

centromere

Area where the chromatids of a chromosome are attached

interphase

period of the cell cycle between cell divisions

G1

cell grows

S phase

The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated.

mitosis

part of eukaryotic cell division during which the cell nucleus divides

cytokinesis

division of the cytoplasm

prophase

Chromosomes become visable, nuclear envelop dissolves, spindle forms

prometaphase

The second stage of mitosis, during which the nuclear envelope fragments and the spindle microtubules attach to the kinetochores of the sister chromatids.

metaphase

Chromosomes line up in the middle of the cell

anaphase

Phase of mitosis in which the chromosomes separate and move to opposite ends of the cell

telophase

mitotic spindle breaks down, cell elongates, nuclear envelopes reform

centrosomes

Microtubule-organizing centers that help to form and organize the mitotic spindle during mitosis

cleavage furrow

The area of the cell membrane that pinches in and eventually separates the dividing cell

cell plate

A double membrane across the midline of a dividing plant cell, between which the new cell wall forms during cytokinesis.

anchorage dependence

The requirement that to divide, a cell must be attached to a solid surface.

density-dependent inhibition

The phenomenon observed in normal animal cells that causes them to stop dividing when they come into contact with one another.

growth factors

Factors that stimulate the cell to divide.

cell cycle control system

A cyclically operating set of molecules in the eukaryotic cell that both triggers and coordinates key events in the cell cycle.

benign tumor

An abnormal mass of cells that remains at its original site in the body.

malignant tumor

A cancerous tumor that is invasive enough to impair the functions of one or more organs.

metastasis

The spread of cancer cells beyond their original site

cancer

any malignant growth or tumor caused by abnormal and uncontrolled cell division

C4 Plants

A plant that prefaces the Calvin cycle with reactions that incorporate CO2 into four-carbon compounds, the end product of which supplies CO2 for the Calvin cycle.

cell division

Process by which a cell divides into two new daughter cells

chromatin

entire complex of DNA and proteins in a cell

cell cycle

series of events in which a cell grows, prepares for division, and divides to form two daughter cells

G2

Final preparation phase. Organelles are duplicated

M phase

mitosis and cytokinesis

mitotic spindle

An assemblage of microtubules and associated proteins that is involved in the movements of chromosomes during mitosis.

tumor

mass of rapidly dividing cells that can damage surrounding tissue