Biology Cells and Tissues

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Questions and Answers

What is the cell considered as?

structural & functional unit of life

What is the purpose of the reading material for paramedics?

To cover theoretical knowledge required by students (correct)

To provide advanced education on anatomy

To teach complex medical procedures

To train paramedics for surgery

What are the four basic types of human tissues?

epithelial, connective, muscular, nervous

Which organelle is often referred to as the 'powerhouse of the cell'?

Mitochondria Signup and view all the answers

Human cells are eukaryotic and have distinct membrane-limited nuclei.

True Signup and view all the answers

The ____________ separates the cytoplasm from the extracellular environment.

plasma membrane Signup and view all the answers

Match the cellular function with the specialized cell type:

Movement = Muscle and other contractile cells Synthesize and secrete components of the extracellular matrix = Fibroblasts, cells of bone and cartilage Convert physical and chemical stimuli into action potentials = Neurons and sensory cells Ion transport = Cells of the kidney and salivary gland ducts Signup and view all the answers

What is the main function of Simple Cuboidal Epithelium?

Secretion and absorption Signup and view all the answers

Where is Simple Columnar Epithelium found?

Lining of the digestive tract Signup and view all the answers

Stratified Squamous Epithelium is found in the lining of the digestive tract.

False Signup and view all the answers

___ tissue is found in the lining of the urinary bladder and ureters, specialized for stretching.

Transitional Epithelium Signup and view all the answers

Match the following specialized Connective Tissues with their descriptions:

Adipose Tissue = Connective tissue with fat-storing cells Cartilage = Firm, flexible tissue found in areas like the nose and joints Bone (Osseous Tissue) = Provides solid support, protects organs, and serves as a reservoir of ions Blood = Consists of red and white blood cells in a liquid matrix Signup and view all the answers

What is the function of the liver?

Produces bile, detoxifies harmful substances, and stores nutrients. Signup and view all the answers

Which organ stores and releases bile into the small intestine?

Gallbladder Signup and view all the answers

The upper respiratory tract filters, humidifies, and warms incoming air, and contains sensory receptors for the sense of ______.

smell Signup and view all the answers

The respiratory system maintains homeostasis by adjusting the rate and depth of breathing to meet the body's oxygen demands.

True Signup and view all the answers

Where is the hypothalamus located?

In the brain Signup and view all the answers

The pituitary gland is often referred to as the 'master gland'.

True Signup and view all the answers

What is the primary function of the parathyroid glands?

Regulate calcium levels in the blood, influencing bone health and nerve function Signup and view all the answers

The adrenal glands produce hormones such as cortisol and adrenaline, which are involved in stress response and ____________.

metabolism Signup and view all the answers

Match the following reproductive organs with their primary functions:

Ovaries = Produce eggs and hormones such as estrogen and progesterone Testes = Generate testosterone and control male reproductive functions Fallopian Tubes = Transport eggs from the ovaries to the uterus; the site of fertilization Signup and view all the answers

What functions do bones serve in the human body?

All of the above Signup and view all the answers

What is the name of the dense connective tissue that bone is composed of?

mineralized matrix Signup and view all the answers

The hip bone is composed of two fused bones.

False Signup and view all the answers

______ protect the thoracic organs.

Rib Cage Signup and view all the answers

Match the bones with their descriptions:

Scapula = Flat, triangular bone on the upper back. Has bony prominences for muscle attachment. Femur = Longest and strongest bone in the human body. Articulates with the hip and knee joints. Clavicle = Long, S-shaped bone connecting the sternum to the scapula. Part of the shoulder girdle. Signup and view all the answers

What is the role of the clavicle, sternum, and ribs in the human body?

Create a protective cage around the thoracic organs Signup and view all the answers

How many vertebrae are there in the human spine?

33 Signup and view all the answers

Match the following types of joints with their associated movements:

Hinge Joint = Flexion and extension Ball-and-Socket Joint = Flexion, extension, abduction, adduction, rotation Pivot Joint = Rotation Ellipsoid Joint = Flexion, extension, abduction, adduction Condylar Joint = Permits movements in two directions Saddle Joint = Flexion, extension, abduction, adduction, circumduction Signup and view all the answers

The quadriceps muscles are located in the back of the thigh.

False Signup and view all the answers

The _________ is the largest muscle in the buttocks, responsible for hip extension.

Gluteus Maximus Signup and view all the answers

What are the main components of the genital (reproductive) system for females and males?

The main components are gonads (ovaries and testes) that produce oocytes (eggs) and sperms, ducts that transport them, and genitalia. Signup and view all the answers

The anatomical position refers to the body position as if the person were standing upright with the head, gaze, and toes directed ________.

anteriorly (forward) Signup and view all the answers

Which plane divides the body into right and left halves?

Median plane Signup and view all the answers

The endocrine system consists of structures that secrete hormones, including both endocrine and exocrine glands.

False Signup and view all the answers

Match the following cell membrane functions with their descriptions:

Selective Permeability = Regulates the passage of ions, molecules, and nutrients Barrier Protection = Acts as a physical barrier between internal and external environments Cell Signaling = Transmit signals from the external environment to the inside of the cell Cell Adhesion = Allows cells to adhere to each other and form tissues Signup and view all the answers

Study Notes

Introduction to Anatomy

Human anatomy is the study of the structures that make up the human body
There are different ways to study anatomy, including:
- Regional anatomy: studying the body as organized into segments or parts
- Systemic anatomy: studying the body as organized into organ systems
- Surface anatomy: studying structures that can be observed or palpated beneath the skin
- Radiographic, sectional, and endoscopic anatomy: studying structures in the living, as they are affected by muscle tone, body fluids, and pressures, and gravity
- Clinical anatomy: applying anatomical knowledge to the practice of medicine

The Levels of Structural Complexity

Anatomy encompasses various levels of complexity, from the microscopic level of cells to the macroscopic level of organs and organ systems

The Cytoplasm

The cytoplasm is the part of the cell located outside the nucleus
It contains organelles such as:
- Mitochondria
- Endoplasmic reticulum
- Golgi apparatus
- Lysosomes
- Ribosomes
The cytoplasm is responsible for various cellular functions, including:
- Movement
- Adhesion and tight junctions between cells
- Synthesis and secretion of components of the extracellular matrix
- Conversion of physical and chemical stimuli into action potentials
- Synthesis and secretion of enzymes
- Synthesis and secretion of mucous substances
- Synthesis and secretion of steroids
- Ion transport
- Intracellular digestion
- Lipid storage
- Metabolite absorption

Cellular Organelles

The plasma membrane (plasmalemma) is the outermost component of the cell, separating the cytoplasm from its extracellular environment
The plasma membrane functions as a selective barrier that regulates the passage of certain materials into and out of the cell and facilitates the transport of specific molecules

Nucleus

The nucleus is a membrane-bound organelle found in eukaryotic cells (cells with a defined nucleus)
The nucleus contains genetic material, including DNA, and is often referred to as the control center of the cell
The nucleus regulates cellular activities and houses the nucleolus, involved in ribosome production

DNA (Deoxyribonucleic Acid)

DNA is a molecule that carries genetic instructions for the development, functioning, growth, and reproduction of all known living organisms
DNA consists of two long strands forming a double helix, composed of nucleotides with adenine (A), thymine (T), cytosine (C), and guanine (G) bases
DNA is organized into structures called genes, which encode specific proteins

RNA (Ribonucleic Acid)

RNA is another type of nucleic acid involved in protein synthesis and various cellular functions
RNA is usually single-stranded and contains uracil (U) instead of thymine
There are different types of RNA, including:
- Messenger RNA (mRNA)
- Transfer RNA (tRNA)
- Ribosomal RNA (rRNA)

Chromosomes

Chromosomes are structures composed of DNA and proteins found in the cell nucleus
Chromosomes contain genes and carry hereditary information
Humans typically have 23 pairs of chromosomes (46 in total), with one set inherited from each parent

Mitochondria

Mitochondria are double-membraned organelles found in the cells of most living organisms, including humans
Mitochondria are often referred to as the "powerhouses of the cell" due to their primary role in energy production
Mitochondria generate adenosine triphosphate (ATP), a molecule that provides energy for various cellular activities

The Endoplasmic Reticulum

The endoplasmic reticulum (ER) is a cellular organelle involved in the synthesis, folding, modification, and transport of proteins and lipids
The ER consists of a network of membranes within the cell and comes in two forms:
- Rough ER, studded with ribosomes on its surface
- Smooth ER, lacking ribosomes

The Golgi Apparatus

The Golgi apparatus, or Golgi complex, is a cellular organelle responsible for processing, packaging, and distributing molecules within or outside the cell
The Golgi apparatus consists of flattened membrane-bound sacs called cisternae
Key functions of the Golgi apparatus include:
- Modifying and sorting proteins and lipids synthesized in the endoplasmic reticulum (ER)
- Adding molecular tags, such as carbohydrates (glycosylation)
- Further refining the structure of these molecules
- Sorting and packaging them into vesicles for transport to their final destinations

Lysosomes

Lysosomes are membrane-bound organelles within cells that contain enzymes responsible for breaking down and digesting cellular waste, damaged organelles, and foreign substances
These enzymes are acidic and work optimally in the acidic environment within lysosomes
Lysosomes are also involved in the degradation of cellular organelles through a process known as autophagy, where damaged or obsolete organelles are engulfed and digested

Cell Cycle

The cell cycle represents a self-regulated sequence of events that controls cell growth and cell division
The cell cycle involves the development of a single, fertilized egg cell to form a complex, multicellular organism
The cell cycle involves cellular replication, growth, and progressive specialization (differentiation) for a variety of functions### Cell Division
Mitosis: the process of cell division that results in two identical daughter cells with the same number of chromosomes as the parent cell
Occurs in all body cells except for male and female germ cells
Involves one round of cell division, resulting in two daughter cells with the same number of chromosomes
Key stages of mitosis: prophase, metaphase, anaphase, telophase

Meiosis

The process of cell division that takes place in the germ cells to generate male and female gametes
Requires two rounds of cell division, resulting in four non-identical daughter cells with half the number of chromosomes
Key stages of meiosis: meiosis I and meiosis II
Involves the pairing of homologous chromosomes, followed by the separation of sister chromatids

Difference between Mitosis and Meiosis

Mitosis: results in two identical daughter cells with the same number of chromosomes, involved in growth, repair, and maintenance of body tissues
Meiosis: results in four non-identical daughter cells with half the number of chromosomes, involved in the production of gametes

Tissue: Introduction

A human tissue is a group of cells with similar structure and specialized function
Tissues combine to form organs, and organs work together in organ systems
Four basic types of tissue: epithelial, connective, muscular, and nervous

Epithelial Tissue

Covers body surfaces and lines organs, serving as a protective barrier
Five types of epithelial tissue:
- Simple Squamous Epithelium: thin and flat cells, found in areas where diffusion or filtration occurs
- Simple Cuboidal Epithelium: single layer of cube-shaped cells, involved in secretion and absorption
- Simple Columnar Epithelium: single layer of elongated cells, involved in absorption and secretion
- Stratified Squamous Epithelium: multiple layers of flat cells, providing protection
- Stratified Cuboidal Epithelium: multiple layers of cube-shaped cells, relatively rare in the human body
- Pseudostratified Columnar Epithelium: appears stratified but all cells touch the basement membrane, found in the respiratory tract
- Transitional Epithelium: specialized for stretching, found in the lining of the urinary bladder, ureters, and urethra

Connective Tissue

Provides a matrix that supports and physically connects other tissues and cells together to form organs
Major component of connective tissue is the extracellular matrix (ECM)
ECM consists of different combinations of protein fibers (collagen and elastic fibers) and ground substance
Specialized types of connective tissue:
- Adipose Tissue: connective tissue in which fat-storing cells or adipocytes predominate
- Cartilage: firm, flexible tissue found in areas like the nose and joints
- Bone (Osseous Tissue): provides solid support for the body, protects vital organs, and encloses internal cavities
- Blood: consists of red and white blood cells in a liquid matrix (plasma)

Muscle Tissue

Responsible for movement by contracting and relaxing
Three types of muscle tissue:
- Skeletal Muscle: voluntary control, striated appearance, found in muscles attached to bones
- Cardiac Muscle: involuntary control, striated appearance, found in the heart
- Smooth Muscle: involuntary control, non-striated appearance, found in the walls of internal organs

Nervous Tissue

Forms the human nervous system, which is the most complex system in the body
Consists of neurons and supporting cells called glial cells
Anatomically, the nervous system has two major divisions: central nervous system (CNS) and peripheral nervous system (PNS)

Organ Systems

Organs are structures composed of two or more tissue types, working together to perform specific functions
Organ systems are groups of organs that collaborate to carry out particular physiological functions
Examples of organ systems: cardiovascular, respiratory, digestive, nervous, muscular, skeletal, and endocrine systems### Upper Respiratory Tract
Common ailments: common cold, sinusitis, and allergic rhinitis
Involves inflammation of nasal passages, sinuses, or throat
Symptoms: congestion, sneezing, and sore throat
Proper care and hygiene: handwashing, avoiding exposure to respiratory viruses

Lower Respiratory Tract

Components: trachea, bronchi, bronchioles, alveoli, and lungs
Trachea (windpipe): connects larynx to bronchi, allowing air passage
Bronchi: divide into two, one leading to each lung
Bronchioles: smaller air passages, continue to divide into even smaller tubes
Alveoli: tiny air sacs, where oxygen and carbon dioxide exchange occurs
Lungs: primary organs of lower respiratory tract, consisting of lobes filled with bronchi, bronchioles, and alveoli
Pleura: double-layered membrane surrounding lungs and lining chest cavity

The Nervous System

Composed of neurons and supporting cells
Transmits electrical impulses, enabling communication within the nervous system
Found in brain, spinal cord, and peripheral nerves

Neurons

Function: transmit electrical signals
Structure: cell body, dendrites, and axon
Types: sensory neurons, motor neurons, and interneurons

Neuroglia (Glial Cells)

Function: support and protect neurons
Types: astrocytes, oligodendrocytes, Schwann cells, microglia, and ependymal cells

Synapse

Function: junction between neurons, allowing signal transmission
Components: presynaptic terminal, synaptic cleft, and postsynaptic membrane

Central Nervous System (CNS)

Components: brain and spinal cord
Function: integration and processing of information

Brain

Divisions: forebrain, midbrain, and hindbrain
Gray and white matter: gray matter contains neuron cell bodies, while white matter consists of myelinated nerve fibers
Functions: responsible for cognitive functions, sensory processing, motor control, and regulation of involuntary bodily functions

Cerebrum

Functions: responsible for conscious thought, voluntary actions, sensory perception, and language
Divisions: two hemispheres, each further divided into four lobes (frontal, parietal, temporal, and occipital)

Cerebellum

Function: coordinates voluntary muscle movements, balance, and posture

Brainstem

Components: medulla oblongata, pons, and midbrain
Functions: regulates vital functions like breathing, heart rate, and blood pressure

Peripheral Nervous System (PNS)

Components: nerves outside the CNS
Function: connects the CNS to the rest of the body, facilitating communication

Autonomic Nervous System (ANS)

Controls involuntary bodily functions, maintaining internal balance and responding to stress
Divided into sympathetic and parasympathetic branches

Endocrine System

Complex network of glands that produce and release hormones
Major glands: hypothalamus, pituitary, thyroid, parathyroid, adrenal glands, pancreas, ovaries, and testes

Skin

Largest single organ of the body
Consists of three main layers: epidermis, dermis, and subcutaneous tissue
Functions: protects against pathogens, UV radiation, and physical trauma, regulates body temperature, and enables perception of touch, temperature, and pain

Urinary System

Regulates the balance between water and electrolytes, and acid-base balance
Excretes metabolic wastes, excess water, and electrolytes in urine
Components: kidneys, ureters, bladder, and urethra

Male Reproductive System

Consists of several organs that work together for the production and delivery of sperm
Components: testes, epididymis, vas deferens, seminal vesicles, prostate gland, and penis

Female Reproductive System

Consists of several organs that work together for the production and delivery of eggs
Components: ovaries, fallopian tubes, uterus, cervix, vagina, and external genitalia

Menstrual Cycle

Involves a series of hormonal changes orchestrated by the hypothalamus, pituitary gland, and ovaries
Leads to the release of an egg from the ovary (ovulation) and preparation of the uterus for a potential pregnancy

Mammary Glands (Breasts)

Multicellular gland that produces milk for breastfeeding or during lactation
Composition: lobules, ducts, adipose tissue, and connective tissue

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