Physiology: Ch 3 review

These flashcards cover key vocabulary terms related to cell structure and genetic control as outlined in the lecture notes on human physiology.

Plasma Membrane and structure/components

A selectively permeable membrane that gives form to the cell and separates it from the external environment.

hyperplasia

An increase in the number of cells in a tissue or organ, resulting in its enlargement.

hypertrophy

An increase in the size of individual cells in a tissue or organ, leading to its enlargement.

DNA replication

before cell division, the double helix splits apart. 2 new moleules are made from the original one each with half old and half new DNA= semiconservative replication

P53 gene

A tumor suppressor gene that plays a critical role in regulating the cell cycle and preventing cancer by inducing apoptosis in cells with damaged DNA.

G1

G1

The first phase of interphase in the cell cycle, during which the cell grows and prepares for DNA replication.

S

The 3rd phase of interphase in the cell cycle, when DNA synthesis occurs to replicate the cell's genetic material.

G2

The second phase of interphase in the cell cycle, where the cell continues to grow and prepares for mitosis.

mitosis

The process of cell division where a single cell divides into two identical daughter cells, involving karyokinesis( nuclear division)

cytokinesis

cell division

protein degradation

proteins outside th elysosomes are tagged by a molecule called ubiquitin, makring them for degradation by proteasome

Messenger RNA (mRNA)

modified pre -mRNA that contains the code to make a specific protein

transfer rna (tRNA)

carries amino acids to mRNA for translation

ribosomal rna (rRNA)

forms ribosomes with proteins; site of translation and acts as an enzyme

histones

proteins that package DNA in the nucleus to form chromatin

cytoskeleton

A dynamic network of protein filaments and tubules providing structural support and shaping the cell, as well as facilitating intracellular transport and cell division.

autophagy

lysosomes digest worn out or damaged organells and proteins

apoptosis

lysosomes aid in programed cell death

nuclear envelope

A double membrane structure surrounding the nucleus, it regulates the exchange of materials between the nucleus and cytoplasm.

nucleolus

A dense region within the nucleus where ribosomal RNA (rRNA) is synthesized and ribosome assembly begins.

microfillaments and microtubules

Thin protein fibers that provide structural support and are involved in cell movement. Microfilaments are composed of actin, while microtubules are made of tubulin.

vacuoles

Membrane sacs that store nutrients, waste products, and others, helping maintain turgor pressure in plant cells.

plasma membrane components

phospholipid bilayer with a hydrophonic center and embedded proteins that move laterally (fluid-mosaic model).

• semipermeable protein channels- selectively allow substances to travel

• carbohydrates- (glycolipids and glycoproteins) serve as antigens and regulators

• chloesterol- flexibility

integral and peripheral membrane proteins function

integral: span the membrane peripheral: embeded on one side

support, transport control

Cytoplasm

material within a cell excluding the nucleus, containing organelles and cytosol.

cytosol

The liquid portion of the cytoplasm, primarily composed of water, dissolved ions, and organic molecules.

Nucleus

The organelle that contains DNA and directs cell activities.

Ribosomes

Granular particles made of protein and RNA, responsible for protein synthesis.

Endoplasmic Reticulum (ER)

A system of interconnected membranes involved in protein and lipid synthesis, consisting of rough (with ribosomes) and smooth (without ribosomes) sections.

Golgi Apparatus

Stacks of flattened sacs that modify, sort, and package proteins and lipids for secretion.

Mitochondria

Double-membraned organelles that produce ATP through aerobic respiration.

Lysosomes

Organelles containing digestive enzymes that break down waste materials and cellular debris.

Peroxisomes

Organelles that contain enzymes often detoxifying harmful substances and hydrogen peroxide.

Centrosome

An organelle that organizes spindle fibers and distributes chromosomes during mitosis.

Chromatin

Fibrous strands of DNA and protein that contain genetic information.

Endocytosis

The process of taking large materials into a cell by engulfing them in a vesicle.

Exocytosis

The process of exporting large molecules, like proteins, from the cell via vesicles.

Cilia

Tiny, hair-like structures that help move substances across the cell surface.

ex: respirtory tract and fallopian tubes

Flagella

A whip-like structure that propels a cell forward; notably present in sperm cells.

Microvilli

Folds in the plasma membrane that increase surface area for absorption and diffusion.

Gene Expression

The process through which a gene's information is used to synthesize a functional gene product, usually a protein.

Transcription

The process of copying a segment of DNA into messenger RNA (mRNA).

Translation

The process of synthesizing proteins from mRNA at the ribosome.

Epigenetic Inheritance

The phenomenon where silenced genes are passed to daughter cells without changes in the DNA sequence.

Meiosis

Two consecutive cell divisions that result in the production of gametes (ova and sperm)