Biology 1 Honors Cell Growth and Division

biology honors 1, chapter 11 cell growth and division

Cell Growth

Living things grow by producing more cells.

Limits to Cell Growth

Factors that restrict cell growth include DNA overload and inefficient material exchange.

DNA Overload

In larger cells, the demand on DNA increases, potentially leading to malfunction.

Surface Area to Volume Ratio

This ratio limits cell size; cells need a large surface area relative to their volume for efficient material exchange.

Asexual Reproduction

Reproduction involving one parent, producing quickly and often with low genetic variation.

Sexual Reproduction

Reproduction involving two parents, producing new offspring with high genetic variation.

Mitosis

The process of cell division leading to two genetically identical daughter cells.

Cytokinesis

The process of dividing the cytoplasm into two new daughter cells.

Chromosome

A structure that carries genetic information, visible during cell division.

Chromatid

One half of a duplicated chromosome; sister chromatids are identical copies.

Centromere

The point where two sister chromatids are joined together.

Interphase

The phase of the cell cycle between divisions, where the cell grows and replicates DNA.

Cell Cycle

The series of events that cells go through as they grow and divide.

M Phase

The phase of the cell cycle that includes mitosis and cytokinesis.

G1 Phase

The first stage of interphase where growth and protein synthesis occur.

S Phase

The stage of interphase where DNA replication occurs.

G2 Phase

The second stage of interphase, preparing for cell division.

Prophase

The first phase of mitosis where chromosomes become visible and the nuclear envelope breaks down.

Metaphase

The stage of mitosis where chromosomes line up at the cell's equator.

Anaphase

The phase of mitosis where sister chromatids are separated and move toward opposite poles.

Telophase

The final phase of mitosis where chromosomes begin to disperse and the nuclear envelope re-forms.

Cyclins

Regulatory molecules that control the timing of the cell cycle.

Internal Regulators

Molecules that function inside the cell to regulate the cell cycle.

External Regulators

Molecules that function outside the cell to stimulate growth and division.

Checkpoint Control System

Regulatory checkpoints in the cell cycle that ensure processes occur accurately.

Cancer

A disorder where cells lose the ability to control growth, often due to mutated genes.

p53 Gene

A gene that regulates the cell cycle; mutations can lead to cancer.

Mutation

A change in DNA nucleotide sequence that can lead to dysfunctional proteins.

BRCA1 and BRCA2 Genes

Genes associated with increased risk of breast and ovarian cancer when mutated.

Apoptosis

The process of programmed cell death, crucial for eliminating damaged cells.

Cell Cycle Restart

The reinitiation of the cell cycle after it has been halted by internal or external signals.

Chromatin

The material of which the chromosomes are composed, consisting of DNA and proteins.

Nucleosome

A structural unit of chromatin, consisting of a segment of DNA wrapped around histone proteins.

Loop Chromosome

A chromosome structure that forms during cell division to help organize DNA.

Cell Plate

A structure that forms during cytokinesis in plant cells, leading to the formation of a cell wall.

DNA Replication

The process by which a cell duplicates its DNA before mitosis.

Spindle Fibers

Filaments that help to separate sister chromatids during mitosis.

Nuclear Envelope

The double membrane that surrounds the nucleus, breaking down during prophase.

Mitosis vs Meiosis

Mitosis leads to identical daughter cells, while meiosis produces gametes with genetic variation.

Embryonic Development

The process by which an embryo forms and develops, requiring rapid cell division.

Genetic Variation

Differences in DNA sequences among individuals, important for evolution.

Cellular Stability

The maintenance of normal cell functions and stability in response to internal and external stresses.

Cancer Risk Factors

Elements that increase the probability of developing cancer, such as genetic mutations.

Cytoplasm

The material within a cell, excluding the nucleus, where many cellular processes occur.