Backanatomy unit 3
04:26
Terms in this set (24)
The cytoplasm is the area between the inside of the cell membrane and the outside of the nucleus.
Cytosol is the gel-like fluid within the cytoplasm where organelles are suspended.
Organelles are structures performing specific functions within the cell, either membranous or non-membranous.
Non-membranous organelles are in direct contact with cytosol; membranous organelles are isolated by membranes.
Ribosomes contain rRNA and proteins; they can be free (floating in cytoplasm) or attached to rough ER, synthesizing proteins.
The centrosome has two centrioles and pericentriolar matrix; it organizes microtubules and the spindle apparatus during cell division.
The cytoskeleton provides structural support and includes microfilaments, intermediate filaments, and microtubules.
Microfilaments are made of actin; they assist in muscle contraction, cell locomotion, cytokinesis, and increase surface area.
Intermediate filaments are composed of tissue-specific proteins like keratin, providing mechanical support.
Microtubules are hollow tubes of tubulin acting as tracks for organelle movement; they form centrioles, spindle apparatus, cilia, and flagella.
Mitochondria have a double membrane, contain their own DNA and RNA, and are the site of ATP synthesis.
Smooth ER lacks ribosomes and synthesizes lipids; rough ER has ribosomes and synthesizes proteins for secretion or membranes.
The Golgi apparatus modifies, packages, and delivers proteins to the cell membrane, lysosomes, or for secretion.
Lysosomes contain digestive enzymes that break down bacteria, viruses, and worn-out organelles.
The nucleus is the cell control center with a double membrane nuclear envelope, nuclear pores, nucleolus, and contains DNA.
Chromatin is dispersed, thread-like DNA and proteins in the nucleus during interphase, appearing as beads on a string.
Haploid cells (gametes) have 23 chromosomes; diploid cells (somatic) have 46 chromosomes arranged in 23 homologous pairs.
Homologous chromosomes are pairs with the same length and centromere position, carrying genes for the same traits but possibly different alleles.
Autosomes are chromosome pairs 1-22 carrying somatic traits; the 23rd pair are sex chromosomes determining biological sex (XX or XY).
The cell cycle has interphase (growth and DNA replication) and the mitotic phase (mitosis and cytokinesis).
During interphase, the cell grows, performs metabolic activities, and duplicates chromosomes in preparation for division.
G1: growth and metabolism; S phase: DNA synthesis and chromosome replication; G2: preparation for mitosis.
Sister chromatids are identical chromosome copies joined at the centromere, where kinetochores form for spindle attachment.
The kinetochore is a protein structure on the centromere where spindle microtubules attach during cell division.