Cell Structure and Function Overview

<p>They lack membrane-bound organelles. (C)</p> Signup and view all the answers

<p>Usage of energy to build complex molecules. (B)</p> Signup and view all the answers

<p>All organisms are made up of cells. (A)</p> Signup and view all the answers

<p>Site of energy production. (C)</p> Signup and view all the answers

<p>They contain a nuclear membrane. (A)</p> Signup and view all the answers

<p>Storage of genetic material and regulation of gene expression (A)</p> Signup and view all the answers

<p>To control movement of proteins and RNAs across the nuclear envelope (B)</p> Signup and view all the answers

<p>Ribosomal RNA (rRNA) (C)</p> Signup and view all the answers

<p>Some cells, like certain algae, may have only one, while others can have thousands (C)</p> Signup and view all the answers

<p>Chromatin is a dense mass of coiled DNA found in the nucleus (D)</p> Signup and view all the answers

<p>Houses enzymes for DNA and RNA synthesis (B)</p> Signup and view all the answers

<p>Size and shape of mitochondria (C)</p> Signup and view all the answers

<p>It synthesizes ribosomal RNA and assembles ribosome subunits (C)</p> Signup and view all the answers

<p>6% (C)</p> Signup and view all the answers

<p>Both B and C (A)</p> Signup and view all the answers

<p>They are embedded within the hydrophobic region of the membrane. (A)</p> Signup and view all the answers

<p>Its hydrophobic fused ring system (B)</p> Signup and view all the answers

<p>They are easily removable without disrupting the membrane. (B)</p> Signup and view all the answers

<p>Proximal compartment (D)</p> Signup and view all the answers

<p>Post-translational modifications (C)</p> Signup and view all the answers

<p>To release proteins via exocytosis (C)</p> Signup and view all the answers

<p>Wilson disease (B)</p> Signup and view all the answers

<p>It rejects proteins without signal peptides. (B)</p> Signup and view all the answers

<p>Digestive body (C)</p> Signup and view all the answers

<p>1955 (B)</p> Signup and view all the answers

<p>Cancer and neurodegenerative diseases (B)</p> Signup and view all the answers

<p>Acid phosphatase (D)</p> Signup and view all the answers

<p>Acidic pH around 5 (A)</p> Signup and view all the answers

<p>Autophagy (A)</p> Signup and view all the answers

<p>Lysosomal enzymes are released into the cytoplasm (C)</p> Signup and view all the answers

<p>Nuclear transfer enzymes (C)</p> Signup and view all the answers

<p>By releasing enzymes that damage external biopolymers (A)</p> Signup and view all the answers

<p>Facilitates penetration of the ovum (B)</p> Signup and view all the answers

<p>Lipid hydrolyzing enzymes (D)</p> Signup and view all the answers

<p>They are amphipathic. (D)</p> Signup and view all the answers

<p>Oleic acid (A)</p> Signup and view all the answers

<p>It determines the fluidity of the membranes. (C)</p> Signup and view all the answers

<p>Cholesterol (C)</p> Signup and view all the answers

<p>Long-chain fatty acids (D)</p> Signup and view all the answers

<p>Sphingolipids (D)</p> Signup and view all the answers

<p>They consist solely of single bonds. (D)</p> Signup and view all the answers

<p>50% (A)</p> Signup and view all the answers

All living organisms are made of cells, all cells come from pre-existing cells, and cells contain genetic material for cell function and replication.

Simple cells without a nucleus or membrane-bound organelles. Examples are bacteria.

Complex cells with a nucleus and membrane-bound organelles. Examples are animal and plant cells.

Small size, lack of membrane-bound organelles, DNA not enclosed in a nucleus, and no complex proteins called histones.

Larger than prokaryotic cells, highly organized internal structure with many membrane-bound organelles, the nucleus houses genetic material, and reproduction involves mitosis and meiosis.

The basic structural and functional unit of all living organisms.

Every organism is made of one or more cells.

Cells pass on genetic material to new cells.

The nucleus, which contains most of a cell's DNA, directs cell activities.

A double membrane surrounding the nucleus, separating it from the cytoplasm.

Structures in the nuclear envelope that regulate the passage of molecules into and out of the nucleus.

DNA in the nucleus tightly coiled into a mass, which is stained darkly.

Synthesizes ribosomal RNA (rRNA) and assembles ribosome subunits, a non-membranous organelle.

The 'powerhouse' of the cell, responsible for generating energy (ATP).

Mitochondria vary in number, size, and shape depending on the cell type and its metabolic activity.

The fluid-like substance inside the nucleus, containing enzymes for DNA/RNA synthesis.

The Golgi complex sorts, modifies, and packages proteins and lipids produced by the endoplasmic reticulum (ER) for transport to their final destinations.

The receiving side of the Golgi complex, where proteins and lipids from the ER arrive via vesicles.

The middle part of the Golgi complex where proteins are modified and glycosylated (sugars added).

The shipping side of the Golgi complex, where modified proteins are packaged into vesicles for transport to their final destinations.

The Golgi complex selectively sorts proteins based on signal peptides, sending different proteins to different destinations.

Cellular organelles containing digestive enzymes to break down waste materials and cellular debris in cells.

The process where vesicles fuse with the cell membrane to release their contents outside the cell.

Mutations in Golgi proteins can cause defects in membrane trafficking, resulting in diseases like Wilson's disease.

Approximately 6% of the lipids in grey matter brain cells are gangliosides.

Cholesterol is a common membrane component in animal cells but not in plants or prokaryotes. It helps regulate membrane fluidity.

These proteins are embedded within the membrane, interacting with its hydrophobic region.

These proteins are bound to the membrane surface by weaker interactions, such as ionic bonds or hydrogen bonds.

Peripheral membrane proteins can be removed without disrupting the membrane structure.

Lysosomes are membrane-bound organelles found in animal cells. They contain enzymes that break down waste products and worn-out cell parts.

Lysosomes are absent in red blood cells (erythrocytes).

The pH inside lysosomes is acidic (around 5), while the pH of the cytosol is neutral (around 7).

Acid phosphatase is an enzyme used to identify lysosomes. It is specific to this organelle.

Lysosomal enzymes are essential for breaking down various molecules: proteins, carbohydrates, lipids, and nucleic acids.

Autophagy is a process where lysosomes digest damaged cell parts, like mitochondria and the endoplasmic reticulum.

When a cell dies, lysosomes release their enzymes into the cytoplasm, leading to autolysis (self-digestion).

The acrosome is a specialized lysosome found in sperm. It helps the sperm penetrate the egg during fertilization.

Lipids are the building blocks of cell membranes, forming the structural framework.

Lipids have a dual nature: a hydrophilic (water-loving) head and a hydrophobic (water-fearing) tail.

Describing a molecule with both hydrophilic and hydrophobic regions, like lipids.

Fatty acids are crucial components of many membrane lipids. They form the nonpolar tails of these molecules.

Fatty acids with no double bonds in their carbon chain. They're straight and tightly packed.

Fatty acids with one or more double bonds in their carbon chain. They are bent at the double bond and less packed.

A type of lipid that forms the cell membrane's backbone, often with phosphatidyl groups.

Important lipids found in biological membranes, especially in the brain, including myelin sheath.